12 bolt arrived from Moser! We ordered Eaton Posi through TTP, but after opening her up, uh...we somehow got a Detroit Tru Trac. (The brochure actually says Tractech Trutrac)

My mechanic has put in 5 of these for Street and Drag strip F-bodies, always Eaton Posi's. That's the ticket according to him.

Maybe the change has something to do with the fact that I ordered 33 spline. So maybe the true track is the "33 spline with posi upgrade- $100" that TTP offered (Eaton was standard.)

Anyway, Before I go crating it all back up, could this be a good thing?
Will this thing hook up at the strip as well as an Eaton with clutches?
Is it more breakable than an Eaton? (my mechanic says it can't be as strong)
Or Is it more for roadracing and will hurt launches with one tire spinning?

Thanks for your advice fellow 12 bolters!
Ram

 

I would argue that it is less breakable than the eaton. It operates with actual gears instead of clutches so there's nothing to wear out or fail on your giving you a one wheel peel. I am putting a true trac behind my 725rwhp car after reviewing all other options. Of course this is a 9" not that it makes much difference on the diff.

 

Well that is saying a hell of lot! I'll "only" have 625 RWHP at best on spray, so I guess I'm good with both the 12 and trutrac?

So would you say Zero downside for launching at the strip and I guess better for going around corners to boot?

Thanks for setting me straight by the way, I feel relief! Saw the post where one guy had a piece of metal go through the gears, dremeled the chips smooth and it's working.

Thanks.
Ram

 

If you're M6 then I don't know how long you'll have the 12bolt w/625+rwtq but most of the vendors here recommend the true trac for most applications where a spool is not desireable. Definitely what you want for cornering as I will be doing some road race etc. I'll be running ~900rwhp next year through the true trac so I'll be one of the first to see if it will hold up at that level. The true trac can be "loaded" with shims to adjust the bias of the lockup.

 

If i lay off the spray it will be around 500 rwtq... That would be a shame!
Well I'm digging in the pages and just read your post for 04/08 What's the Best Diff. Option for High Power and Cornering?? And I'm just not sure what to do. I really Applaud your experimenting though man!
Thanks for your help!

 

If I was a hardcore drag guy then I prob would have went with detroit locker or spool but my setup is geared towards top speed, handling, and cornering. I'll probably only run a few passes at the strip to get a time for the heck of it. Good luck in your search.

 

I would take the true trac over the eaton anyday myself...call yourself lucky and keep it!!!!

 

The Truetrac is a beefier set-up, though a little cheaper, than the Eaton Posi. Normally you will have less problems with a Truetrac than you will with an Eaton, and it will provide you with two solid patches of rubber. I seldom sell an Eaton unit anymore, as the Truetrac has replaced it. Eaton now owns the Truetrac, by the way.
Limited slip additive is not needed with the Truetrac, as there aren't the clutches like there are in the Eaton. Bob

 

Stick with the truetrac!

 

Sounding pretty good guys!...Beefier, less problems, Eaton owns tru trac as the "replacement"... and I like those two solid patches of rubber.

Hey Bob are we OK for around 600 rwhp ya think? Dropping clutch around 4000, shifting at 6500. Truth be told, it's 99% a street car, maybe 15 passes in a year at the track.

Bob, I paid 100 more than I would have with you, minus the expert advice. I'll definately keep you in mind for the blown Z down the road.

Last question: After changing the cheap gear oil on breakin, what kind of oil is best? I do have the T.S. moly additive which I would like to add in to whatever we use.

Lucas 85/140 plus the moly additive?

Thanks everybody!
Ram

 

Ditto!

 

Stay True! I have a locker but prefer True.

 

i just got the true track, cuz i couldnt find anyone that said anything bad about it... i'd keep it if i were u

would it be bad to have the fiction modifier in the rear also even though it doesnt need it?

 

Lots of thumbs up here...appriciate it guys. Keeping Tru~!

I can't get anyone to reply over on 10 sec. club..just wanted to check with those guys too.

On the friction modifier, probly not a problem, but, let's ask Bob...


Uh, BOB?

 

how do you load the tru trac? where do you install the shims? how do you adjust the bias of the lock up?my tru trac is loose as hell and has a lot of play between the lock up, between forward and reverse, accel and decel. my rear/diff only has 3000miles on it and the clunking caused by the loose play between accel and decel is killin me, its so f#$#$ annoyin lol....it is a beast of a diff tho, and puts down great traction.

 

The Truetrac does not have clutches, so no friction modifier is needed. Bob

 

I got true track also for my 9in . You might want to consider getting the 9in sine your a manual i dont know if that 12bolt is going to hold up to that much shock off the line .

 

A little off topic...

Hey Bob,

Resurrecting this old post...I was referring to Moly additive, not friction additive. I want to keep the new 12 bolt quiet as possible for long as possible. Moly additive supposedly has some "cushioning" for hard launches aside from friction reduction. This is completely different from Slick 50's PFTE who were told by the government to back off on their false advertising claims a few years ago. What are your thoughts on Moly? (Or anyone else?)

It helped my howling ten bolt on my other car I would say by about 30%. Maybe it will keep howling at bay on the 12 bold Tru Trac...

Check out:

http://www.tsmoly.com/catalog/index.php?cPath=5_23

GD-401 MP Moly Treatment for Gear Oils imparts the benefits of moly into plain engine oil. Moly is a solid film lubricant with a low coefficient of friction and an affinity for steel and other metals. The moly decreases friction of the two counter-moving sliding surfaces of gear teeth by filling in microscopic pores of the metal surfaces and plating out over the surfaces. GD-401 lessens metal-to metal contact to reduce friction and wear. See "Frequently Asked Questions" for more about "moly"
GD-401-008 Single 8 oz bottle $25.05

 

What is Moly?

"Moly" is molybdenum disulfide, a chemical compound with the symbol MoS2. Moly is the term commonly used in the lubricants industry.

Moly was first used as a lubricant as early as the 17th century, but its merits were not fully appreciated until aerospace researchers, during the 1940's and 1950's, discovered its unique ability to function in the extreme environment of deep space. It was during this time that Climax Molybdenum Company, the principal supplier of molybdenum products worldwide, introduced lubricant-grade moly on a commercial scale. Since that time, moly lubricants (greases, fluids, and dry films) have proven themselves in a wide variety of military, industrial, off-highway (construction and mining), and automotive applications.

The lubricating properties of moly come from its structure of stacked plates. Each moly particle, on a microscopic scale, can be visualized in simple terms as a series of buttered bread slices one on another. The bread represents layers of molybdenum atoms and butter represents layers of sulfur atoms. The bread and butter units align themselves parallel to the metal surfaces in contact and adhere by mechanical and physical forces to the peaks and valleys of the metal surfaces. Because the butter layers are weak, the layers of the bread and butter easily slide sideways on each other while still adhering to the opposed metal surfaces. Metal-to-metal contact is minimized because the moly fills in the peaks and valleys, and it creates a protective film over the metal surface. Exceptionally smooth contact surfaces are established as the moly film develops, thus reducing friction, wear, and its attendant rise in temperature. The moly film is not permanent, but it can be replenished from the moly contained in the bulk lubricant.

 

Moser won't warranty anything if anything other than standard non synthetic gear oil is used, and this probably applies to the Moly GD-401 MP.
The very best way of assuring you will have a set of quiet gears is to do four to five 10 minute break in idle runs with the rear jacked up in the air. You want to let the rear cool in between runs. Once this is done, don't get on it for 500 miles. Bob