• NAXJA is having its 18th annual March Membership Drive!!!
    Everyone who joins or renews during March will be entered into a drawing!
    More Information - Join/Renew
  • Welcome to the new NAXJA Forum! If your password does not work, please use "Forgot your password?" link on the log-in page. Please feel free to reach out to [email protected] if we can provide any assistance.

detroit truetrac, sanity check/advice needed

jonoabq

NAXJA Forum User
Location
albuquerque, nm
I've got a 99' auto 4x, Chrysler 8.25 rear, Dana 30 front that I recently installed Detroit Truetracs in. Mostly a DD but with lots of use in the desert sand in the summer, NM & Co snow in winter.

The rear Trutrac is dead quiet, however the front has a soft squeak that sounds like a fingers or a rubber squeegee on wet glass when turning at parking lot speeds. (It does this in the dirt & pavement, in 2WD or 4WD) I was under the impression that they were quiet and after multiple attempts at contacting Eaton the answer I got was less than spectacular. They essentially said "it should be fine" the Dana 30's come with preload that could cause the squeak, which is causing my bull**** meter to go off.

I was wondering if anyone out there in NAXJA land has any relevant experience to add to my understanding of the soft noise that is now driving me batty.

Thx,

Jonathan
 
I've got a D30 - TrueTrac in my '98, and it's pretty quite. Works like it's supposed to, with no complaints. Could your squeak be unit bearing related or axle u-joint related?

If you feel it's still your TrueTrac and you feel motivated, you can perhaps rebuild it, as detailed in this thread...

http://www.naxja.org/forum/showthread.php?t=1062865
 
As its only two weeks old and under warranty for a year from date of purchase I'd be reluctant at best to rebuild it at this point. Right now I'm trying to collect as much relevant information as possible and either live with it or send it back. The entire front end is either "new or improved" within the last six months and in good working condition...the only thing that changed was the install of the Truetracs and ARB covers, which would have zero effect.
 
How have you isolated the noise to the Truetrac and not some other moving part?
There are a lot of things that could be making noises in a turn.
Have you jacked the front end up and tried rotating the wheels by hand to see if the noise can be duplicated?
I would think that the noise would be different between 2WD and 4WD if there was something seriously wrong inside the Truetrac.
 
Nothing else made noise until the truetrac went in. Put it up on a lift and spun up the front wheels both manually and with 4WD engaged, went from full lock side to side with nothing goofy, no unwanted noise. It only makes noise under load so getting it in the air revealed nothing unfortunately.
In the mornings when the diff is cold from sitting overnight it is pretty quiet, but as I get a few miles down the road and things come up to operating temps the squeegee on wet glass "squeak" comes back...low speed turns only, anything above 15/20 mph it is either not there or drowned out by traffic/driving noise.
 
Check your drive shaft probably the double Cardon joint. Pull the front shaft and drive it tell me if you still have a squeak.
 
Kinda sounds like a unit bearing problem. Did you torque them down to 175 ft/lbs? Are they the original units?
 
I vote is double Cardon joint. When they disconnected the shaft they let it fall and messed up the joint.
 
I have a true trac in my 8.25. No squeak noise except from the tires if giving it gas around a turn. Probably not from the truetrac.

I'd bet its something else. Start by pulling the front shaft and see if it goes away.
 
I have had Truetracs in my '93 XJ for 13 years or so and they have never squeaked. However, a friend did have a very squeeky front Truetrac straight after installation. I thought it was bad enough for him to get the installer to do it again. This was going back at least 10 years ago, but I am fairly certain he said that the fix was reinstalling with new bearings without using a housing spreader and shimmed accordingly.
 
Straight line any speed, completely quiet. Turning at slow speeds you can hear it, right or left...at some point normal driving noise drowns it out, or its not there. When I leave for work in the am, and everything is cooled off its totally silent, until about 20 minutes later it starts to warm up and make noise.
The latest conversation with Eaton tech support today was interesting as the tech support guy immediately went to "are you running Valvoline?" to which I relied "yes" (its Napa, but Napa is made by Valvoline). His experience was that swapping out the diff oil to Shell, Castrol, Mobile should make the noise go away... The conversation was longer and more detailed but thats the gist of it.
So tonight I swapped out the diff oil for Castrol 85/140 (I live in the desert) and will see what happens before I pull the trigger on refitting or returning it. At this point I'm cautiously optimistic at best, but its a quick/easy test. After that I'll isolate it from the driveshaft...then move to bearings, etc. if needed.

thanks again for all the input.
 
Last edited:
With the Castrol 85w-140 in, I went for a 30 min drive...and its about 98% quieter. Encouraging so far, if I make it through my seven hour desert trip this weekend with the same results I'm gonna call this one closed.
Now it is quite possible that the issue was the change in oil weight, and not the brand/quality of oil. Won't know the answer to that question until the fall when I switch back to 85w-90 for the cold months.
 
600 miles of NM & Az up to 9000' and 100 degree temps, mix of forest roads and highway. With the Castrol 85w-140 in the differential its...quiet. I got a couple suuuper soft chirps near the continental divide but they we so light that unless you were really paying attention they would have gone unnoticed.

So of the four Truetracs that come with preload (Dana 30 is one of the four) they may be more or less sensitive to the oil brand/viscosity than Eaton advertises.

a) According to Eaton, Valvoline/Napa bad, Castrol, Shell, Mobile good. Unsure about how much viscosity contributed to the squeaking but I'll be better able to answer that question when I switch back to 85w-90 for the winter.

This solution took many phone calls to friends, Eaton tech support, postings on multiple XJ web forums and about four weeks to sort out. Thanks for all the input.
 
600 miles of NM & Az up to 9000' and 100 degree temps, mix of forest roads and highway. With the Castrol 85w-140 in the differential its...quiet. I got a couple suuuper soft chirps near the continental divide but they we so light that unless you were really paying attention they would have gone unnoticed.

So of the four Truetracs that come with preload (Dana 30 is one of the four) they may be more or less sensitive to the oil brand/viscosity than Eaton advertises.

a) According to Eaton, Valvoline/Napa bad, Castrol, Shell, Mobile good. Unsure about how much viscosity contributed to the squeaking but I'll be better able to answer that question when I switch back to 85w-90 for the winter.

This solution took many phone calls to friends, Eaton tech support, postings on multiple XJ web forums and about four weeks to sort out. Thanks for all the input.

Any update on this? Has it stayed quiet after a few months? Iv just run into this same issue on my JK. going into the shop tomorrow to change the gear oil after my breakin period. They originally filled it with synthetic. Hoping I dont have to pull it out for warranty.
 
I just wanted to thank you for this post and following up after your fluid change jonoabq. I was starting to freak out after my front trutrac started making the same squeegee sound (very good way of describing it) and found your post. I'm still under the break in period so new oil going in by the end of the week anyhow, I'm hoping for the best.
 
My true trac are quite but I do find they work better with 85w140 gear oil. The 75w140 synthetic is too slippery. I also found this to be true with my Ausie locker as it is a whole lot noisier with synthetic gear oil.
 
Bringing this back from the dead to say this: THANK YOU SO DAMN MUCH for posting your solution. I looked high and low for this info and couldn't find anyone having the "squeegee" noise from their True Trac. You nailed it. I'll be switching diff lube tonight!!

WHEW!!
 
Back
Top