T-case Rattle

I am getting a rattle out of the T-case I think.  I only seem to get it at high speed, over 30, and under uphill load.  Putting it into 4x4 does not change it.  Putting in the clutch stops it, I assume because the load is removed.  I only get it in 3rd gear, but I assume that is from the speed as opposed to anything else.  The bearings in everything are new.  It is not a tinny rattle I would almost call it a high speed knock.  It is definitely not coming from the engine.  It does not seem to have any effect on performance.  I have tries wiggling all the shifters while it is happening.  No change.  I have checked to make sure it isn't the pedals rattling around.  


Edited by 52 M38 - 27 Aug. 2014 at 7:19pm

Any chance the exhaust pipe is hitting against the stay cable bracket which is attached to the transmission cross-member? Or maybe a broken exhaust hanger somewhere? I've had both problems that resulted in odd noises but only under certain load and/or RPM conditions.

On mine one of the 1/4 -20 bolts that hold the sheet metal transmission cover on was too long and was bumping against the transmission itself. Kind of a low pitch solid sounding rattle. But it was not constant..it would do it enough to make you crazy though... 

And they do make a stethoscope for automotive use..they are not expensive.....and that way you may save your ear and molars if you were to hit a bump!

I will do some searching this weekend and try to determine the culpret.  I may take the PTO cover off the trans and have peek in there to make sure all is well. 

Joe Friday wrote: What style E brake do you have? The M38A1 style external shoe will rattle against the drum at high speed if adjusted incorrectly or in my case the outside of the drum is coated with gear lube.

I will look into that.  I plan to pull e brake and look.  Mine has a brake just like the 2a.

No resolution on this, it has quieted down.  I have decided that since it is not from the engine.  I'm not going to worry about it.  If some component eats itself i will solve it then.  Thanks for the help. 

52 M38, if you rode in my Jeep and heard the gear noise you would never complain about yours again.

I think that was it.  No rattle on my drive today.  I know lots of people have problems with the heat riser seizing, I apparently had the opposite problem.  i will let you know if it comes back.