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Hi, 

I have 32RH trans in 1995 4.0 YJ 150k miles. It works perfectly except there are some noises (probably trans related) that recently started and bother me:

  1. After Jeep has been sitting overnight - when I start it in Park, there is some rattling/grinding noise that starts around 2k rpm. This is more pronounced when it is cold outside, like 35F. Noise only occurs in Park and only on 2k+ rpms. I'm not 100% sure that it is gone once everything heats up, it could be that it is just more silent but present. I think this is 100% coming from trans because changing the gear eliminates the noise.
  2. Noise when driving - this happened 3-4 times so far. I was driving on a highway and since I have 3.07 and 33s engine was working at 1500 rpm or below all the time. When I got to the incline, I pushed the pedal and engine went to around 2k rpm. Nose similar to first one started, but after 5-6 seconds it was gone and after that no matter how much I pushed the pedal I could not replicate it. It seems to happen only after driving on low rpm for a long time and then pushing the pedal. I could not feel any drivability issues when this happened. I'm not 100% sure this comes from trans but it sounds like that and is definitely related to rpms.. If it was engine I guess I'd have bigger issues.

Trans was never rebuilt. Since I did complete restoration of vehicle a year ago I took transmission out and did following:

  1. Adjusted linkages/cables
  2. Replaced all seals
  3. Changed entire fluid/filter
  4. Adjusted both bands
  5. Cleaned governor and removed burrs from its housing
  6. Cleaned valve body - seemed ok

In the meantime I had to take it out twice because flexplate reluctor ring was slightly out of round and was throwing off CPS signal. Since all replacement plates had issues (poor manufacturing) I took original one to the machine shop where they grinded it to spec. However, I'm not sure if they balanced it.

Having all of this in mind I thought about a couple of things about noise no.1: 

  1. Bad check valve - converter fluid drains back. Since converter is not being filled in park, something rattles. I excluded the pump from the equation since it works in any gear. Problem with this is that even after filling the converter in Neutral (and noise goes away immediately after shifting to neutral) noise still occurs in park.
  2. Flexplate bolts hitting the dust shield - shield seems a bit bent. However this does not explain why noise is in park but not in neutral.
  3. Issues with torque converter - on stall test it was around 2k rpm which by FSM seems to be OK, so I'm not sure about it..

Am I missing something here? 

 

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zidodcigalah...My first picks would be the anti-drainback valve to the torque converter or a clogged cooler issue—or both.  All RH/RE transmissions have the inherent flaw of earlier 3-speed RWD Chrysler transmissions (904, 999 and 727):  By valve body design, there is no lube pressure or fluid flow to the torque converter and front pump bushing when the transmission is in Park.  These transmissions rely solely on the anti-drainback valve to keep the converter fluid full.  When the valve fails or sticks open, the front pump bushing runs without fluid in Park.  Eventually, the front pump bushing burns up.

Here is my comprehensive coverage of this issue.  Sonnax has the cure for Chrysler RWD RE/RH transmissions.  Our 48RE (truck purchased new) became symptomatic by not moving immediately when shifted from Park to drive after being parked for long periods.  I caught the problem immediately before any front pump damage occurred:

https://www.4wdmechanix.com/Survival-Upgrades-for-Jeep-and-Dodge-Ram-Automatic-Transmissions?r=1

These are additional mods I made later, some applying only to the overdrive versions:

https://www.4wdmechanix.com/ram-truck-47re-and-48re-transmission-in-chassis-survival-upgrades-from-bd-diesel-performance/

The other issue, whether the front pump is damaged or not, would be the torque converter itself.  The converter may have issues.  If you wind up replacing the front pump or pump bushing, I would get a rebuilt converter at the same time.  Clean/flush the cooler properly, too.  If you don't perform the Sonnax upgrade(s), install a new anti-drainback valve.

If you do the Sonnax upgrades to the valve body, Sonnax recommends removal of the anti-drainback valve once you have full-pressure lube to the converter and front pump in Park.  I left the anti-drainback valve in place because it is part of the 2005 Ram OEM hose to the cooler.  The valve is not restricting flow and is likely stuck open.  If I change the cooler and hose/fittings, I will likely eliminate the anti-drainback valve.  Sonnax full-pressure lube to the converter in Park is the solution.

I found this and other AT cooler flushing products at Summit Racing.  Read the reviews and listings for similar products:

https://www.summitracing.com/parts/atp-at200

Moses

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  • Moses Ludel changed the title to YJ Wrangler 32RH Transmission Grinding and Rattling Noise

Thanks Moses. I'm aware of the design flaw. I will test fluid circulation after drainback valve and after cooler to check for restrictions. The only symptom that is missing so that I can be 100% sure that valve is the problem is delayed engagement. I don't feel any delay, even after 3-4 days...

Could bushing damage cause huge damage in other parts of the transmission system? I'm thinking about scratches on it, not complete failure and breakage. I took some photos while I was doing a vehicle rebuild and I can't see any huge damage on front bushing, maybe slight scratches that to me seem normal for 150k vehicle.

I will try to make a video of the noise and put it here so it can be helpful for someone else with the same issue.

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zidodcigalah...Looking forward to hearing the noise in a video...It's possible the converter stays filled enough to not produce the delay.  A very low converter fluid level creates the delay issue.  If you rule out the front pump bushing, there could be a converter unit issue.

Yes, the main issue with the front pump bushing would be clearance.  (Scratches might indicate too much bushing clearance or fluid bleeding off and not lubricating the front pump bushing.)  Too much clearance, generally from wear, could create noise or front pump rattle. 

Keep in mind that these transmissions also have a history of starving for fluid and pressure on steep inclines.  The filter/pickup does not stay submerged enough to draw fluid.  The converter, front pump and apply units (bands and clutch packs) will suffer from lack of fluid pressure and flow.  Does that sound familiar?

Moses

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  • 3 weeks later...

Well I finally found some time to check up on this. To be honest, inside vehicle it sounds like rattle while on this video it sounds more like pump. 

Here is the link to video: https://www.youtube.com/watch?v=cGtHNTRaNAI 

This is cold start, and after starting vehicle I kept it around 2000rpm. The clunk you hear occasionally is me switching from Park to Neutral - instantly as I switch to Neutral (or any other position) noise disappears. As soon as I switch back to Park it is there again. Noise seems a bit more silent after driving couple of miles.

I took it for a 60 miles ride. Since I have 3.07 gearing and 33 inch tires, when I'm cruising it is around 1300rpm. If I cruise for 5-10 mins and then give it more throttle on uphill (so it downshifts to 2nd and 2000+rpm) - same noise appears but after 3-4 seconds it is gone and won't happen again unless I repeat the same steps.

Last time I had transmission out, I drove it 3 miles with 1,5 pints of fluid less than max.. I'm not sure if this made the problem worse, but noise in Park was already there before that.

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Zidodcigalah...Good audio/video capture...A failing or failed anti-drainback valve may have started this entire problem.  Your Park to Neutral end of noise phenomenon is likely the converter recharging when you move the manual valve in the valve body from Park to Neutral:  The pump bushing gets charged with oil again.  When the bushing is dry or without enough fluid pressure to stabilize the pump rotor, the pump rattles and buzzes. 

At this stage, the front pump is damaged.  The noise sounds like a classic front pump rattle from a worn front pump bushing and the metal-to-metal grating within the pump.  The bushing wear begins from running dry while in Park mode (likely because the anti-drainback valve was not holding).  As a rule, when the bushing wears enough, it takes out the pump.  Low pump pressure results from the pump wear, and this compounds the problem, making it even more difficult to refill the converter.

Low pump pressure could be your issue when you tip in the throttle at low speeds and the noise occurs.  Before replacing the pump and/or converter, I would run a hydraulic pressure test, using the factory criteria for "normal" pressure at specific engine rpm.  I believe you will discover low pump and hydraulic system pressures.  This will help establish a baseline for the work ahead.

Unless you want to go another round with a new anti-drainback valve, I would do the Sonnax valve body upgrades that I suggested.  That will provide full fluid pressure and flow to the converter when in Park.  Keep in mind that the front pump and bushing metal has run through the system and likely contaminated the oil cooler.  Flush or replace the cooler.

Note:  It might be cheaper to replace the entire radiator and cooler assembly.  I bought a new OEM replacement radiator through Summit Racing for $72, and it came with a new cooler built in.  The plastic side tank radiator has lasted for over 60K miles and still works fine.  The manufacturer builds OEM radiators at Mexico.  Works for me. 

An automatic transmission is a closed system and should only pick up fluid through the filter.  However, when an internal part fails, especially the front pump or converter, the interior components get contaminated.  Abrasive debris winds up in the converter and cooler.

If hydraulic pressure tests low, make sure the clutches and bands are not worn out.  (Test for no slippage on shifts or under load.)  If you suspect band and clutch frictions wear, it's time for dissassembly, thorough cleaning and a bench rebuild of the entire unit.  That's not as extreme as it sounds.  A rebuild kit for a 32RH is relatively inexpensive.  You need basic, universal automatic transmission tools like a K-D clutch spring compressor, a press and improvised sleeves or collars for carefully replacing worn bushings.  The 32RH is basic 904/999 Chrysler RWD architecture dating to the sixties.

Moses 

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Thanks a lot Moses, all of this makes perfect sense... I really can't thank you enough for helping me on this. I guess I'll have to face the inevitable :)

Since I'm from Europe, ordering/finding spare parts is quite problematic and expensive because of high shipping costs and duties, so I will first try to determine the scope of the damage. For now I don't feel any slippage (even when the noise is present while driving). I will do hydraulic tests and check if line pressure is below spec (probably is). 

  1. If pressure is low and pump is shot - do I have to replace converter too? I was thinking about replacing entire pump/seals, flushing cooler and reusing converter.
  2. In case of some wonder where pressure is still within specs - could I get away with only front bushing/seals replacement for now? In this scenario, I'd rather do pump when time comes for entire trans overhaul

In any case, Sonnax upgrades are a must. Now, even replacing manual valve would eliminate that noise in Park, but still that would only mask real problem until I repeat that low speed scenario. I will keep you updated, someone might find this useful.

Thanks again for helping me on this and multiple other occasions. Your forums might not have membership base like some other ones, but it has invaluable knowledge and content thanks to you.

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zidodcigalah...You're welcome...It's always good to know your options and the possible parts damage.  To begin, let's discuss the least expensive get by or "survival" approach, knowing that a rebuild is likely down the road. 

Recommendation:  USE THE FACTORY SERVICE MANUAL WHEN ATTEMPTING THIS WORK.  YOU WILL BETTER UNDERSTAND THE FUNCTIONS, SEQUENCING, DISASSEMBLY AND ASSEMBLY OF COMPONENTS.  THE USE OF CORRECT TOOLS IS ILLUSTRATED THROUGHOUT THE CHAPTER ON 30RH/32RH TRANSMISSION REBUILDING.  eBay is one source for a used factory service manual, there is usually a print copy or duplicate CD (PDF format) available.

Check hydraulic pressures before doing any other work.  Use the factory service manual test methods and pressure guidelines.  If pressure is marginal (on the low side), take the transmission out of the chassis with the converter attached, as described in the shop manual.  This is the practical method of removal.  Hold the converter in place within the converter housing.  I use strands of mechanics wire and a block of wood against the converter hub to keep the converter from sliding out of the pump and off the reaction shaft.  Inspect the flexplate and bolts to be sure that loose flexplate flange bolts or a cracked flexplate are not involved in the rattling noise.

Once the transmission is safely out of the chassis, remove the converter carefully from the transmission.  If the converter has been acting okay, you can get the unit flushed while it is separate from the transmission.  This is not the same as rebuilding, and by design, you will never clean a converter thoroughly by "flushing".  Eventually, you will need to have the converter unit rebuilt, which can be done at Europe.  Rebuilding a torque converter means cutting the shell in half on the centerline/weld seam, removing the internal parts, repairing/replacing damaged pieces, rewelding the shell halves together, then balancing the assembly.

If no converter or flexplate damage is evident, I would target the front pump next.  You can carefully remove the front pump by itself.  To do this, first tighten the front band to prevent the internal parts (drum, clutch, etc.) from sliding out the front of the case.  (If these parts slide out, you might be disassembling the transmission completely to get them back in place.)  The front pump can be removed with two slide hammers.  Do not try to pull on one side of the pump at a time, the pump will cock and bind.  Remove the mounting bolts and install the two slide hammers in the threaded locations designed for these slide hammer pullers.  Carefully and evenly tug the pump forward and loose. 

Disassemble and rebuild the pump.  If the gears are still reusable (doubtful but remotely possible), you can restore the pump with a new pump bushing;  if needed, a sleeve repair kit can also be installed.  Inspect for wear, and make sure the gears are within tolerance.  Replace the gears if necessary.  Assemble the pump with new seals and gasket, do not use sealant on the new pump mounting gasket.

The interlocking sealing rings at the rear of the pump require care as you reinstall the pump evenly and without excess force.  Align parts carefully;  slight loosening of the front band may be necessary to center up parts during the pump installation but do not loosen the band prematurely.  Be sure the drum, clutch and other parts do not drift forward during pump installation.  

If you find that you want to rebuild the entire transmission at this time, I quickly came up with this Omix-ADA rebuild kit for $186 USD, the free shipping is presumably within the U.S.  This is one U.S. retailer, there are many, including NAPA Auto Parts:

OMIX-ADA 19001.04 JEEP WRANGLER TJ/YJ AUTOMATIC TRANSMISSION REBUILD KIT

https://jeepsarelife.com/omix-ada-19001-04-automatic-transmission-rebuild-kit

The Chrysler transmission rebuild kits often cover many model years.  Your transmission's architecture is found in cars, light trucks and later Jeep models.  The 904 dates to the early sixties although Chrysler warns not to use early parts in the later 30RH/32RH transmissions.  From Europe, you may find rebuild kits available from Turkey, Israel and elsewhere in the Middle East since Raybestos has been a quality clutch frictions source built around the globe. 

The kit shown at the link includes bushings.  It is possible to change out transmission bushings with a bottle jack press or sometimes an arbor press.  You can improvise on the collars or sleeves needed to remove and replace bushings.  Make sure to align bushing oil holes with the case, do not apply excessive force to aluminum castings.  Use the OEM bushing positions as a guide when pressing.  I use Sunnen B200L to prevent galling and to reduce risk of bind during bushing press operation.

 https://goodson.com/products/sunnen-press-fit-lubricant

The more difficult parts to source would be the front pump assembly and converter.  Yes, you want a rebuilt converter if you rebuild the transmission.  Rebuilding the original pump may be a necessity.  A parts source, surprisingly with a lot of coverage for this transmission, is Rock Auto.  See the listing below.  I'm not clear what the international/VAT and other issues might be, but Rock Auto pricing is often the best available in the U.S.  Note the listing for a front pump sleeve repair kit and bushing.  If your pump gears are okay (a surprise) and there is excess wear at the pump casting, you may be able to resleeve the pump casting then rebush it:

https://www.rockauto.com/en/catalog/jeep,1995,wrangler,4.0l+l6,1185274,transmission-automatic

A relatively inexpensive tool that works for compressing clutches and changing frictions is the K-D tool below (mine has lasted years) and the less expensive versions like the CTA tool:

https://www.amazon.com/KD-Tool-Transmission-Compressor-Automatic/dp/B000WZWGK0/ref=sr_1_1

https://www.amazon.com/CTA-Tools-6500-Transmission-Compressor/dp/B00JHKZGOO/ref=sr_1_2

Moses

 

 

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Moses, thanks for this detailed guide. I finally found some time to do hydraulic test. The specs for my transmission is 54-60psi and up to 90-96psi line pressure at full throttle in position "2" and 1000 rpm. I only did this test since main suspect is pump - if I understood well this test is enough to detect failing pump. I could not find any details if this test should be performed with transmission fluid hot or cold.

I put a jack underneath and removed one rear wheel, connected gauge to trans line pressure port, disconnected throttle cable, started engine and set it idle at 1000rpm with my SnapOn MT2500. 

Unfortunately I only had 500psi gauge, and I had a bit of dripping at line port connection (was unable to seal this), I'm not sure if this can affect readings. Gauge scale is not good enough for this task but needle seems to be between 50-55psi and a hair under or at 90psi at full throttle. I'm also attaching a video (because of angle between camera and gauge readings might look higher/lower than they really are). In best case scenario, these values are close to or at lower limits. Is this a sign of bad pump that needs replacement or these values would be even less in that case?

Video link: https://www.youtube.com/watch?v=PQ3zCpgfmKs

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zidodcigalah...You're on the right track.  In the FSM tests that you are using, there is a "Test 4", transmission in Reverse.  This is a true test of pump output pressure.  The test:  "This test checks pump output, pressure regulation and the front clutch and rear servo circuits.  Use 300 PSI Pessure Test Gauge for this test."  Your 500 psi gauge is fine for the test, reasonably accurate.

Using the rear servo port, follow the procedure for Test 4.  You will be running the engine at 1600 rpm and in Reverse.  Be very careful about your vehicle positioning.  I am not comfortable with your jack under one wheel routine.  Can you use 2WD mode and place safe stands under the rear axle at each side to get both wheels off the ground?  This is a lot of rpm and torque applied in reverse.

I prefer at least warm transmission fluid.  Transmission fluid will warm up fast if you do a Stall Test with the transmission.  Do not stall for too long, the test puts a heavy load on the converter and other parts.  Band adjustment should be correct before performing a stall test...If the transmission and converter fail a stall test, you know there is already a problem with the converter overrun clutch or the ability of the transmission's front and rear clutches to hold, which could be worn clutches and/or not enough fluid apply pressure.  Stall test instructions are in the FSM...Warm fluid is better, but make sure you can handle the gauge and not get burned from the exhaust and such.  Let me know that you have the FSM and Stall Test instructions to follow.  If your metallic rattling noise occurs very clearly during a Stall Test, that could indicate a torque converter defect.

When you know that you are safe, follow these steps for Test 4:

1)  Connect pressure test gauge to rear servo port.  [Looking at the rear of the transmission above the oil pan, the rear servo pressure port is at the right side, to the right of the tailhousing/adapter.  The pipe plug faces directly toward the rear.]

2)  Start and run engine at 1600 rpm for the test. 

3)  Move valve body selector lever four detents rearward from full forward position.  This is Reverse range.

4)  Move throttle lever [this is the kickdown or throttle pressure lever, not the engine throttle!] all the way forward then all the way rearward and note the gauge readings.

5)  Pressure should be 145-175 psi with the [throttle pressure] lever forward and increases to 230-280 PSI as lever moves rearward.

This is a valid test because it better reflects the pump's output capacity.  Your other tests are within reasonable range (a bit low but that could be due to the drip/leak).  However, those readings do not reflect the pump's full output.  Let's see what this test turns up before taking the next step.

Moses 

 

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Well, I did rear servo pressure test and stall test. This time I put jacks under both wheels and under differential case. Vehicle was running at 1600-1650 rpm  in reverse, and I disconnected throttle valve cable. The results with trans fluid warmed up are following:

1. Stall test: 2100-2200 rpm. No rattling or any unusual noise.

2. Rear servo: needle bouncing between 150-160psi. When moving lever pressure keeps rising but in the end it starts to quickly bounce between 200-300psi. Occasionally it stops around 250-260psi but it is only fraction of a second. I'm not sure if this is gauge related or pump is unable to keep steady pressure... Even after running test for 10 mins results were always the same, so I'm not sure if this is air in gauge/hose or pump. No leakage at test port this time 

Bands were adjusted about a year ago.

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zidodcigalah...First-off, the shuddering gauge may hold a valuable clue.  Yes, a liquid filled gauge would provide a more stable needle, but there may be more to this.  The good news is the pressures.  They look okay.  Better yet, the stall test does not point to a distinct converter problem like the overrunning clutch.

So, we know a few things:

1)  The pump is working and able to reach suitable pressure.

2)  The overrunning clutch in the converter is not defective and the engine has a slightly high side but okay stall speed (should be 1700-2100 according to the FSM).  There was no "slip" of clutches during the stall test.  This would be indicated by the engine speed flaring up beyond normal stall range.

3)  Your noise does sound like the front pump—a metallic rattle.

I gave thought to all you did initially and since.  You have been very thorough with a professional approach.  My first response was straightforward based upon the Park to Neutral stoppage of the noise, which points to the classic anti-drainback issue that runs the front pump dry.  Typically, the pump bushing becomes damaged from running dry in Park and so forth.  We avoided an immediate transmission removal, and that may have paid off.

The gauge cast a new light on the converter fill issue and noise.  You are missing a key symptom in the anti-drainback problem.  When the drainback valve fails or sticks open, there is a delay when shifting from Park directly to any gear.  This is due to the lack of available fluid in the clutch and band apply circuits.  The transmission acts as if there is no fluid being picked up or allowing the circuits to function.  Damage occurs just like running the transmission low on fluid.

If you do not experience the hesitation or delay when shifting out of Park to a gear, the anti-drainback valve is likely working.  After parking overnight, when there is a delay of engagement during a shift from Park directly to a gear (not stopping in Neutral), the delay is from the converter being filled (anti-drainback valve issue), which delays the fluid flow to the gear apply circuits.
If the only symptoms occurring are 1) the rattle without an obvious delay when shifting directly to a gear from Park and 2) the gauge flutter, I would look for a cavitation or aeration issue.

I ran heavy equipment years ago and worked with hydraulic pumps and cylinders.  When there is fluid cavitation or aeration, the entire system will rattle, hoses shake violently and the pump can make a loud, metallic noise.  This rapid surge and release of pressure can appear on a pressure gauge as severe flutter or hammering.  The gauge type (dry or liquid filled) can matter, so we need to rule out a gauge problem.  What you describe, however, does sound like more than needle "flutter" and could be cavitation or aeration hammering.  The gauge sensation, if reasonably accurate, is a steady hammering or pounding.

Here is an excellent explanation of the difference between cavitation and aeration:

https://www.hydraulicspneumatics.com/technologies/maintenance/article/21884872/cavitation-or-aeration-you-can-hear-the-difference

Cavitation and aeration require a leak source that creates an air gap(s) in the fluid.  Pump pressure can be normal but the air gaps create the hammering effect and possible rattle in the pump.  Let's consider some sources for air getting into the fluid stream, which can become exaggerated with the steady flow of fluid into the converter:

1)  The simplest air source is when the fluid pickup filter has an air leak between the filter and valve body.  This usually shows up shortly after a fluid and filter change.  If the mounting screws loosen over time, this can also start an air leak.  A filter gasket (if used) or O-ring seal can become misaligned or damaged, creating an air leak.

2)  Valve body leak between the separator plates or valve body junction and the transmission case.  Misalignment or warpage of cast plates or the steel separator(s) can also create an air source.  Loose valve body attachment bolts that need re-torque to specification can create air leaks.  Bolts that loosen over time can lead to leaks.

3)  An air leak into the system from a cracked case or fluid passageway (rare and unlikely though possible), any leak on the suction side of the pump;  the pump or pump mounting gasket to the transmission case can be defective and draw air.  An air leak usually means a fluid leak but not necessarily;  a poor fit between the pump housing and transmission case may draw air yet not leak fluid.  If the pump has never been removed, there is less likelihood of a gasket or pump housing leak.

The point here is that you need an air source to put air gaps into the fluid.  The low speed throttle that leads to a rattle when you tip in the throttle, or the rattle when the converter begins to fill as you pull out of Park, each could be clues.  If you are not experiencing gear engagement delay when shifting from Park directly to Drive (1, 2 or Drive) or Reverse, you may have a pump rattle caused by air in the fluid.

See whether you have the Park directly to gear issue after the Jeep has set overnight.  If not, there is likely no drainback valve issue.  Hunt down an air leak source in the fluid lines, filter and valve body.  Try the easier fixes first:  re-torque the valve body bolts and be certain the fluid filter is not drawing air at the filter-to-valve body junction.  If the symptom disappears, try another servo port/Reverse gauge test.  See whether fluid pressure readings stabilize.  The servo port test in Reverse is a better view of the pump function.  Try your current gauge first before using a liquid filled gauge.

Moses

 

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I really appreciate all of your replies. I did remove valve body (but did not disassemble it), and this rattle in Park happened sometime after that (not sure if it happened immediately as it is much more noticeable in cold weather). As far as I know, pump was never removed. I will check filter/valve body for possible leaks. In case that it doesn't solve the problem I will probably drop the transmission again and check front bushing and front pump gear clearance.

Yesterday I saw that fluid level was 1/3 inch above MAX (checked in neutral after driving 30 miles). I read somewhere that fluid above max will be churned by planetary - which in turn creates bubbles. So this might be the reason why rattle on low throttle appeared, as it was not present before. However this does not explain noise in Park as nothing moves at that point.

Anyway, I plan to keep this Jeep for years so at some point transmission rebuild will be necessary. I think I found a good deal on 32RH rebuild kit on ebay for 160$. It contains Red Eagle frictions, Kolene steels, front band, pump bushing and all gaskets/seals. Same supplier also has Sonnax manual and PR valve. I'm still waiting for a reply if they sell pump rebuild kit - I saw they have kit for A518 with front bushing, gear set and seals for 50$. This is a good option for international orders as one supplier provides everything thus minimizing shipping costs, and shipping time is OK. Here is a link to it, please remove it if it is not compliant with forum rules: https://www.ebay.com/itm/Fits-Dodge-A904-TF-6-Transmission-Red-Eagle-Performance-Master-L2-Rebuild-Kit/202573760811

Thank you for your help, I will post results here once I finish working on this issue. I'm an IT guy so if there is anything from that domain that you need help with, feel free to message me :)

 

 

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zidodcigalah...You're welcome...The valve body to transmission fasteners may have loosened or the filter could be an issue.  Easy to confirm by dropping the pan.  If you want to avoid changing fresh fluid again, catch the fluid in a clean drain pan.  In my early days of automatic transmission work, some OEM shop manuals recommended reusing fresher fluid by running it through 100-mesh brass or stainless steel wire cloth.  I buy this cloth from MSCDirect, you should have a local supplier at Europe.  100 x 100-mesh was essentially the oil pickup screen mesh size on vintage automatic transmissions.  You can go up or down in opening size.  Running fluid through the mesh is a good way to identify the fine debris:

https://www.mscdirect.com/product/details/52431319

The fluid overfill can actually cause aeration of fluid.  Parts churning aeration is the reason for an engine crankcase windage tray...We can guess whether air bubbles would survive a pass through the filter.  Regardless, it's always best not to overfill an automatic transmission.  Overfill increases internal pressure in the transmission and can overload or blow out seals. 

From our exchanges, I can tell that you are committed to the Jeep.  You'll work your way through the Park noise issue, I'm sure.

The kit on eBay looks thorough.  The illustrated parts caught my attention, as there is a cone shaped filter depicted at the lower right.  This type filter typically is at the front pump and can cause intermittent fluid flow if packed with debris.  I revisited parts illustrations of the 904 (as far back as Mopar's 1981 catalog listings for Jeep) and could not find this cone filter.  It does not appear in our FSMs for the 30RH/32RH either.  Not sure if the eBay rebuild kit's coverage dates to an even earlier 904 application.  The pan gasket shape looks typical Chrysler. 

One concern, and you likely caught it when reviewing the FSM, is Mopar's mention that the 32RH/30RH units went through a design revision and to beware of parts differences between the earlier (presumably 904/999) units and  your transmission.  Make certain the rebuild kit will work for your 32RH.  The price is right, the kit looks complete for the usual rebuild.  Confirm the fitment.

We can look into the interchange between the A518 front pump and your 32RH front pump.  The A518 is derivative of the A727 unit, which is larger than the 904.  We can compare front pump part numbers between the A518 and a 32RH when you are ready to order.  Below is a Mopar parts schematic diagram for your front pump.

Keep us posted on this one.  We covered a lot of ground with our exchange.  One more possibility, a long shot but worth a check, is excessive crankshaft endplay from a worn thrust bearing or crankshaft cheeks.  This can create noise in itself or cause parts interference further back at the transmission.  This is an unlikely issue but easy to check:  Push the crankshaft rearward at the front damper/pulley;  pry the crankshaft forward while measuring endplay with a dial indicator.  You can use a block of wood at the pry point (timing cover or whatever) and place pry force at the back of the damper.  You're looking for crankshaft fore-and-aft movement.  The endplay specification is in your FSM.

Thanks for the IT insight and offer...You use an MT2500 and would find automotive lab scopes (Pico, Autel Maxiscope, etc.) interesting.  These tools are capable of pinpoint, millisecond wave form diagnostics and troubleshooting.  This is the breakthrough for modern engine and electrical/electronic troubleshooting and diagnostics.  I am planning a how-to video series on scope functions and ways to take full advantage of a PC-based scope.

Moses

 

 

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  • 4 weeks later...

Couple of updates on this thread. I did notice some lag during initial start. Once vehicle has been sitting overnight on slight incline, it would take around a second or two to get into reverse or drive. After that it is almost instant.

I ordered Sonnax manual and pressure regulator valve and will install them and remove adb valve completely as it might be causing restriction. If that doesn't solve the problem, I'll do complete rebuild once trans totally fails :)

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zidodcigalah...Good call on the Sonnax kit.  Sonnax actually recommends removing the anti-drain back valve once you have full pressure running to the converter in Park.  If you drill down at the Sonnax website, there is either a footnote or directions that suggest removal of the anti-drain back valve after this valve body modification.  We are doing any Chrysler A727/A904 derivative RWD transmission a big favor by charging the converter in Park.  

The second or two delay is enough delay to indicate that the converter is draining back when the Jeep parks.  That condition with the transmission in Park can starve the front pump bushing.  It will be interesting to see what these valve body modifications do for the original rattle in Park at 2K rpm.  Let's be optimistic and assume you caught this in time and that the pump and front pump bushing are not damaged.

Let us know the results!

Moses

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