How to Flat Tow a Jeep TJ Wrangler Rubicon

[joemac51]

Have to get your knowledge as I am puzzled.  I asked a local 4X4 shop a question -- "If I wanted to flat (dingy) tow my 2003 5-speed Rubicon, what is the correct procedure to do so?"  I was advised that I cannot flat tow my 2003 Rubicon as the "gearbox does not have a true neutral position".  Is that true or not?

I thought that Rubicon can be flat towed.  Isn't it a dead on true neutral wherein you put the gearbox in Neutral and its fully disengaged?

Joe Mac

 

 

 

[Moses Ludel]

JoeMac51...You do not want to tow with the transmission in neutral.  The transmission output/mainshaft would rotate but there would be no rotation of the counter (cluster) gear for oiling.  You will burn up the NV3550’s clutch/input gear’s counter bore bearing, the rear mainshaft/output bearing, and more.  The correct flat tow procedure for a chain drive transfer case is transfer case in neutral and the transmission in a gear (1^st, 2^nd, a gear that will keep the transmission parts from moving).

These manual transmissions oil by the counter/cluster gear slinging oil upward to lube the bearings and mainshaft gears.  The counter gear rotates from the input (clutch) gear.  With the engine stopped and clutch engaged, the input gear does not rotate.  The counter/cluster gear does not turn.  There is no oil slinging/lubrication to the upper bearings (including the clutch/input gear’s pilot/mainshaft nose), no lube to the transmission’s gears, and no lube to the output/mainshaft’s rear bearing. 

The chain drive transfer case, on the other hand, has a pump that will still lubricate while towing.  The transfer case should be placed in neutral.  The transfer case output will rotate the chain as the vehicle moves, and the internal pump will work.  This provides reasonable lube to the transfer case parts.  However, the longstanding caution is to not overheat the transfer case by towing too fast or long in this manner.  Old timers always stop periodically to check the transfer case for heat when towing.  The use of a modern infrared surface temp testing tool (Harbor Freight version will do for this) will keep you at a distance from the heat. 

In my view, a car hauling trailer remains the best and safest way to tow a Jeep.  There are no concerns about damage, and if anything breaks on a trail, you can trailer home.  I do not flat tow:  Aside from the issues we're discussing here, flat towing can place extreme loads on the steering mechanism…If you do not limit the steer wheel movement when flat towing (never lock the steering column, leave the key in unlocked mode!), the steering can jack to opposite extremes and drag the front tires sideways down the road. 

For these and other reasons, like the car hauling trailer having brakes versus no brakes on most flat towed vehicles, I use a car hauling trailer.  (There have been vehicle-to-vehicle brake systems available in the aftermarket; however, they are involved and mostly ignored.)  Chain drive transfer case era Jeep models flat towed behind motorhomes are notorious for transmission and steering system damage.  A used Jeep 4x4 that was "seldom driven", just flat towed, is not necessarily a bargain.  Check the transmission for bearing and gear cooking.

As a footnote, the automatic transmission models are not exempt from flat towing damage.  Without the engine running, the automatic transmission has no front pump or torque converter activity, and the entire transmission, and especially the output shaft bearing, is susceptible to damage from lack of lubrication if the automatic transmission is left in neutral while flat towing.  For these chain drive transfer case models, the transfer case must be placed in neutral with the automatic transmission in Park to prevent transmission parts from rotating while flat towing.

Moses

 

Edited November 24, 2015 by Moses Ludel