I am in a bit of a conundrum, have read numerous posts (including yours) and thought maybe you might be able to help, if you have time. I have an elementary knowledge of alignment and components, am ok with a wrench, understand geometry completely (Diamond method you presented makes perfect sense to me), but am limited with shop and tools. Although, I have gotten my tractor back to the shop with a screw driver and a vice grip when the ball joint broke in the field, but that is a different story.
A bit of history on my truck. Original owner, 158k miles, New XFR 0* ball joints, new tie rod ends, newer DSS steering stabilizer (source automotive), New gen 3 track bar upgrade w/ pitman arm (source Automotive). There are no other non-OEM components, other than the air filter, and an amsoil bypass oil filter system. Power steering is right on the money, no chatter, whining or vibration in the steering column when turning. This truck has NEVER worn tires uneven. The tires are commercial, e rated, standard stock size tires. Have used the same brand tires since the original OEM's were worn out. I generally get 25k to 35k out of a set of tires, but I never let them get down to the indicators, I live in snow and ice country. This truck has been used as general duty. Occasional (less than 10% of total milage) gooseneck, 5th wheel, bumper pull trailers, or bed loads; ALWAYS below recommended maximum weights, verified by total and axle weights at the co-op or WHP stations.
Now the problem. I installed the track bar and pitman arm upgrade when the OEM track bar bushings wore out. I had a local shop replace the ball joints and tie rod ends as they were worn as well, and they sent it to an alignment shop. When I got the truck back it drifted (not a real pull, but not entirely correct, and definitely more than before the work was done) to the right, even on a flat surface. I was told that the only way it could be fixed was to change out the upper ball joints with offsets and it was as close as it was going to get. Understanding geometry, but not the components involved, this seemed awkwardly incorrect. Seemingly, if the geometry was initially correct, and the worn components were replaced, it should return to the original OEM geometric orientation. Or at least my level of logic and understanding led me to believe that. Unfortunately, I allowed the drift to continue thinking the alignment shop had at least produced an acceptable balance in the system and the drift to the right was just road camber or the the typical performance of a truck getting a bit longer in the tooth. Additionally, the alignment spec sheet did not make it to the repair shop from the alignment shop so I have no idea what he did, or more accurately, what the results of his alignment produced. Eventually, the right side of the passenger tire soon began to show wear, seemingly a camber issue based on my understanding. I took the truck to an alignment shop in Denver, which seemed to make the pull lessen a bit. They said they would email me the alignment report.
Fast forward a few weeks to yesterday. I loaded some steers onto a stock trailer to take to market, about a 100 mile round trip, there was a heavy wind, which I thought was causing an significant increase in the pull to the right. However, when I removed the trailer, the pull did not lessen and now there is wear on the indside of the drivers side tire. I'm not certain if it matters, but while backing the trailer up to the chute (uphill) to unload the steer's, the back tires chattered quite excessively. To the point that I had to engage 4WD which helped back up, but did not really reduce the chatter. in addition, there is also now a bit of a low frequency vibration at highway speed. The steering wheel is now at 45*left when driving as would be expected, but the steering remains tight, and the truck does not wander. When I let the steering wheel go, the truck goes right immediately. I called the Alignment shop in Denver today and had them email me the report, and there is no Caster, Toe, Cross Caster, Cross Camber, Total Toe for the front, and no thrust angle for the rear, and all the 'actual' and 'before' values that are listed are all the same, so I have no reference data upon which I am able to at least begin a diagnosis. I can email you the report if it might help.
I know there is no magic bullet, but having been laid off in october, things are a bit tight financially. I know I have to get an alignment, but my only option here in Wyoming is the guy who said it could not be done without new offset ball joints. I would like to have a better understanding, or at least have a bit of diagnosis prior to going to an alignment or frame shop.
Now the question (finally) - I have not yet replaced my control arm bushings, but have checked them and they seem loose. Is it possible, or probable that the upgrades to the rest of the system, and old control arm bushings have caused the increased right pull and tire wear experienced when the stock trailer was hooked up?
Are there any other components you feel may be causing this particular issue? Are there any questions I should be asking alignment shops to 'test' their knowledge?
Any advice or reference you may be able to provide would be greatly appreciated.
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