Topic: truetrac spline clearance

[hi on lux]

i am using truetrac in my rear, i am hearing a "thud" sound whenever i release the gas pedal on speeds around 20KPH or less, sounded like those of loose crossjoints, but joints seems fine though.

Pulled it out and noticed that there is a little play between the truetrac and the axle shaft , compared to "almost none" when i inserted it to the open diff that i kept.

splines of both the axle or the truetrac seems fine, no wears.

axle bearings shows they need replacement.

Is this normal for the truetrac to behave like this?

will this rear truetrac can be used up front? though i know upon purchase that there is a different truetrac part no. for a toyota 8 diff. i see no difference on the 3rd members of my front and rear.

thanks in advance!

ted
gmt+8

[79coyotefrg]

the truetrac  works on a gear biasing theory,  it  kinda  sounds  like the truetrac  was either installed  with some  really bad  backlash 

i'll  research this tomorrow, 

[ZUK]

You can put the TT in the front if you flip the internal gears....not a tough job. The TT behaves "differently" in the opposite direction.
http://www.discoweb.org/truetracgears/index.htm

ZUK

[hi on lux [OP]]

You can put the TT in the front if you flip the internal gears....not a tough job. The TT behaves "differently" in the opposite direction.
http://www.discoweb.org/truetracgears/index.htm

ZUK

Hey zuk, thanks for the link.

any comment on the rest of my post?

ted

[ZUK]

Never heard of any problems with the TT splines....I don't think you have a prob there. That thud when you let off the gas could be alot of things......motor mount....tranny mount....severely worn driveshaft slip-splines....loose u-bolts on the leafpacks.

[hi on lux [OP]]

hey zuk,

do the spiral gears/center gears of the TT has some sort of "backlash"  , refering in the link you gave, I supposed you had opened a TT. Or they are snug fit too?

btw, upon close inspection before pulling the 3rdmember, thud sound really came from the rear end.

ted

[hi on lux [OP]]

I remember too that before pulling them out,  I tried also driving in reverse, stepping on and off on the gas, there seemed to be no "thuds".

Is there a marking on the TT that it is for the rear/front, aside from the part no. on the box?

[ZUK]

Is it possible that TT you have was designed for front end use? Maybe that could be related to the clunk. I have only peaked in one TT a long time ago but it was a casual visual so I don't know about the backlash. The part number should be scribed or lasered on the TT case somewhere.
That link about flipping the gears was not prepared by me. Actually, someone was kind enough to point it out to me so I bookmarked it.

[hi on lux [OP]]

yes, I am suspecting now that it is for the front. I will be opening up this diff. soon, my vision points to me that the top gears (still pertaining to Mark Olivares' link you gave) that should show a rear TT (clockwise), tells me otherwise. I have to source a puller.

Btw what signs should i look for , with regards to carrier bearings, if it is due for replacement. I am not the original owner of the truck it came from.

[hi on lux [OP]]

update:

my TT with part no. 913A348 , toyota 8 rear, upon opening it up showed it is for the front.

upon doing the TTs spiral gearswap (front to rear set up ) , I still have the sound as described on my 1st post.

[ZUK]

Ok...I know this is over 1 year old...but per your pm's to me yesterday it seems you still have the issue even after taking the TT out and flipping the gears?

Here's the related part numbers for the TT and other lockers...
Positractions & Lockers
Differential---------- ARB Air Locker-- Detroit Locker--- Lockright TRD--------------- Truetrac
8” Toyota Rear--------- ARBRD01---- DET187S-61A---- PT 1610 TRDRN001--------- TT 913A348
8” Toyota Front-------- ARBRD01---- DET187S-61A---- PT 1610 TRDRN001--------- TT 913A318
8” Toyota V6 & Turbo-- ARBRD23 ----DET187S-61B----- PT 1620 TRDVN001 ----------TT 913A321

So while you were inside the TT you found a front part number stamped in it ?

The helical teeth looked just fine?

When are you putting the Aussie in?