Truetrac is CRAP For a 6 speed.
 

With the mods I have listed below and MT ET Streets (bias ply), I bent the splines on the driver side axle and put a bunch of cuts on the worm gears.

I knew something was wrong when every time I would accelerate out of a slow turn I would hear and feel a loud pop or two coming from the rear.

This is after only using it for 1.5 seasons and 20-30 runs per season. I didn't use the nitrous for most of the runs, but I did do second gear burnouts. The best 60' was 1.7 I think (I'm still learning).

What sucks is that Moser recommended these parts for my power level and they're not standing behind them. I guess its the chance you take for dragracing.

So, now I'm gonna spend 900 parts and labor for a spool.

I've been saying those differentials are JUNK for a year and a half...... I have a car sitting in my garage right now with a broken one, it lived for 5 passes in a 420 rwhp h/c car that was detuned for a nitrous hit (kit didn't work, something funky with the wiring/loose connection somewhere) and it still killed the thing in 5 passes. I'm talking 4 runs on drag radials (street car) then we put a 26x8.5 slick on it for 1 pass, and on the return road it was acting like a locker after 5 passes and about 300 to 500 street miles, roughly.

The tru-crap diff, pretty much makes a 9 inch, 12 bolt or S60 into an overweight 10 bolt in the strength department.

I wouldn't put one of those things in anything period.

Broke 2 here. I will eventually swap it out for something.

If this is mainly a street car, I would not go with a spool. Nor would any manufacturer of axles or spools suggest one.

They are great for hard launches in straight lines. That is about it. They will not like turning and put lots of stress on the axles, studs, and the spool when driven on the street.

On my street/strip car, I have (2) center sections. One with a locker for the street, another with a spool for the race track. That also allows me to run a nice gear for the street and a steep gear at the track.

How do you know it wasn't the splines that bent and damaged the unit?
I know true tracs have had their issues but I was just wondering if something else is causing them to fail.

You wouldn't have been any better off with an Eaton, believe me on that. Spider gears like 6 speeds less than true tracs and they're not going to recommend a spool for a street car.

That says it all right there.

900 sounds like a lot, what are you replacing?

i just went thu this same thing. :emb:

https://ls1tech.com/forums/drag-raci...-truecrap.html

YUP he told me about those junkers last year, and I took his advice on a spool, I run mine on the street 90 percent of the time The only downfall is it is harder on tires. But there is way around that too, use a hard tire. The only trick is when turning keep the clutch engaged and power thru it, you will hardly notice its there. TAKE MY ADVICE ON THIS, I tried the detroit locker, and that was the worst mod I ever did. Ended up selling it and buying the spool.

The tires are a warning sign this may not be the best idea. Similar abuse is being done to the studs, your axles, and the spool.

When you turn, you are keeping the locked axles spinning at a fixed rate, although one is trying to go a shorter distance than the other. This is the tire chirping, or the hopping, or the tire wear you experience. Pretty much your driveline is absorbing the abuse in an attempt to provide the differentiation between the inside and outside wheel that a differential would normally provide.

On a race track, you are doing it some in the pits (low speeds) and once a pass coming off the track at a moderate speed. Just you don't race for miles and miles and turn often at decent speeds as you would on the street.

With a spool, if something fails, none of the damage (and the collateral damage a broken axle, broken spool, or sheared studs would cause) would be covered by a warranty.

I love my 31 spline Detroit Locker.

"I love my 31 spline Detroit Locker."
I agree!
W/ my 6T5 Hemi car/5 speed, Strange recommended ONLY a locker for the street. They said the other units would not hold up..But, it was "only" at 650FW...

I seem to be the only person that has a true trac that hasnt broke yet....been going strong for 3yrs now. Mileage wise 6k :P

I thought about pulling mine apart this winter and welding my spring perches to my axle housing and selling the diff and axles for a spool 35 spline set up, but No one will probably buy it now lol

Broke one also, 6spd car, 390 rwhp, 800 miles. Go with the spool.

$300 for labor, which does seem a little high.

$610 for 33 spline axles and spool

Also, this will be a mostly track car.

Too bad you're not in CT, you could bring the car here and I'd help ya do it for cheap... you buy lunch and clean the oil off the floor when we're done and you'd be good :)


I swear... with the prices some people are getting to do simple stuff these days I should start moonlighting as a mechanic out of my garage.

You could try the wavetrac its expensive but you can get it with a 35 spline axles.

Yeah, the guy at Fast Track said I could get a more expensive type of truetrac. Doesn't seem worth it though in my case.

The wavetrac is not a truetrac its a completely different type of differential. It also has a lifetime warranty. Though its hard to say what they can handle since they haven't been out long. Since its mainly a track car spool would be the best choice anyway.

im with you also......i must have been lucky cause mine has survived many 7 grand clutch drops making 550rwhp........dont think i will try it with the new setup though........anyone interested in mine????????

Mine is still working fine, although I have only heard of 1 guy breaking it on a S60.

Get a spool and be done with it.