Truetrac by Eaton

[ssmike]

Question, what will the Eaton posi do for me on a road course or auto cross? I know it's good for the drag strip but how will it react under power out of an apex? Will it allow for the difference in rotation between the inner and outer wheel or will it lock both the same? I'm worried about it causing under steer!

[blazzin1]

Originally Posted by ssmike

Question, what will the Eaton posi do for me on a road course or auto cross? I know it's good for the drag strip but how will it react under power out of an apex? Will it allow for the difference in rotation between the inner and outer wheel or will it lock both the same? I'm worried about it causing under steer!

Mike, I wish I could give you an experience-based answer, but I have not even received mine yet....(should get here today). All I can tell you is exactly what the Eaton website says about it:

"The Truetrac® operates as a standard or open differential under normal driving conditions, allowing one wheel to spin faster or slower as necessary. When a wheel encounters a loss of traction, the gear separation forces take effect and transfers torque to the high-traction wheel. The helical-shaped pinion gears continue to mesh with the side gears with increasing force until wheel spin is slowed or completely stopped. When the vehicle exits the low traction situation, the separation forces cease and the differential resumes normal operation."

Now, how exactly true that is, or how it performs on a road course....I don't know.

[blazzin1]

Originally Posted by JTRJSS

Yes the web site does say NOT to use synthetic gear oil. It states to use petroleum based gear oil. I have the same setup in my camaro.

Just curious where you saw this on their website? I can't find it. Can you provide a link?

[blazzin1]

Well, I stopped in to NAPA tonight and was surprised to see that they had the exact Lucas 85W140 Gear Oil (non-synthetic) that we were discussing earlier. So, I picked up a couple bottles. So, I guess I'm going non-synthetic!!! Still wondering if I should add a couple oz. of friction modifier....just for the break-in period? Redline said it was a good idea....but haven't heard of anyone else doing it.

Oh....and the best news....my Truetrac was delivered today too!!! I'll post up some pics tomorrow, just incase anyone is curious (not really much to see).

[Unobtainium]

I'd really like to know how a good synthetic is not best for this. It's a helical set-up, I'm assuming like a quaife? Interesting stuff though.

[POWERFREAK]

Originally Posted by Unobtainium

I'd really like to know how a good synthetic is not best for this. It's a helical set-up, I'm assuming like a quaife? Interesting stuff though.

I think it has to do with the fact that it has gears, not clutches in the posi-unit.

[JTRJSS]

From the website:

http://www.eaton.com/Eaton/ProductsS...CT_341171etrac


Truetrac

What kind of oil should I use? Can I use synthetic? Do I need friction additive/modifier?
A quality petroleum/mineral based oil works best in the Truetrac units. We do not recommend synthetic oil. Friction additive/modifier is not required.

Can I use the stock bearings?
In most cases the Truetrac units work with the factory (stock) bearings. The exceptions are: 10 bolt 8.5\8.6 GM axles, the “Performance” Dana 35 & 44 and GM12 bolt with 35 spline axles. No other “special” setup is required.

What kind of break-in is required?
The Truetrac units do not require a break in. The unit’s internals will take a little time (depending on driving conditions) to “seat.” Afterwards there will be a slight improvement in its performance.

When does the Truetrac lock up?
The Truetrac is a helical gear limited slip differential and never “locks up”. The Truetrac operates by transferring power from the spinning wheel to the wheel with the most traction. If one tire breaks traction, the amount of rotation (or spin) is controlled. The torque is then sent to the other tire that still has traction.

I use my car on the street and on the strip, will the Truetrac hold up?
On the street, the operation of the Truetrac will be transparent. You will not know it is there until you need it. In racing situations the unit will apply torque to both tires and launch straight as an arrow, time after time.

How much horsepower and torque will the Truetrac take?
There are many factors to consider when determining if a specific differential will last in your vehicle. Horsepower and torque are important factors. However, the weight of the car, tire height/width, the terrain and suspension are all important things to take into consideration.

For example, a setup that uses street tires will live longer because both tires will break loose and spin before any real strain is put on the unit. But as the tire gets wider, the stress on the unit increases because the traction is greater. When in doubt, the best bet is to call us with your specific application and driving conditions.

Can Truetrac be used in the front axles of full time 4 wheel drive jeeps and trucks?
Yes, it can. You will find will find Truetrac differentials to be very smooth yet effective in either end of your vehicle.

Can I repair the Truetrac if I need to?
The worm gears inside a Trutrac are maintenance free, and do not require regular service. Internal failure usually results in the damage of the worm gear pockets. Therefore, they are not rebuildable.

What is the warranty?
The Truetrac unit is covered for one year from date of purchase against defects in materials and workmanship up to a 38.”

[ssmike]

I think that answers my question I started another thread with! It never "locks up" so coming out of an apex on a road course under full throttle the wheels are still rotating individually and the posi just transfers power to adjust for traction loss.

edit: thanks for the link to the website! I should have done that before posting a new thread!

[Hendrix-Engineering]

Originally Posted by blazzin1

Well, I stopped in to NAPA tonight and was surprised to see that they had the exact Lucas 85W140 Gear Oil (non-synthetic) that we were discussing earlier. So, I picked up a couple bottles. So, I guess I'm going non-synthetic!!! Still wondering if I should add a couple oz. of friction modifier....just for the break-in period? Redline said it was a good idea....but haven't heard of anyone else doing it.

Oh....and the best news....my Truetrac was delivered today too!!! I'll post up some pics tomorrow, just incase anyone is curious (not really much to see).

I wouldnt add any,its gear driven and its going to work .I like to change my oil after the 15 min break in run,change the oil let it set over night and drive it 20 min,let kool a few hrs ,drive it an hr under 4000 rpms let it kool over night ,change the oil drive it for about 800-1000 miles and change the oil again .The oil is cheap and doesnt take long to do it.

[blazzin1]

A couple pictures from my very cluttered work bench this morning!!! Sorry for the mess!!! But anyway, here are some pics comparing my new Truetrac to the OEM posi-unit (which still has the carrier bearings and 3.45 ring gear on it). Also is a pic of the OEM carrier main caps, with the factory steel "strap" over the left cap. Sorry, my JRE caps are still with the machinist. The bushings are new Pfadt rear upper control arm bushings, ready to be installed!!! Can't wait to get all this stuff installed!!!

JTRJSS.....Thank You for the very valuable information. Glad I decided to buy the "dino-oil".

[Supercharged SS]

We just installed a JRE / true trac rear. No break in needed. From Teds shop to the Atco staging lanes. The rear is super quiet and preformed flawlessly.

[blazzin1]

Originally Posted by Supercharged SS

We just installed a JRE / true trac rear. No break in needed. From Teds shop to the Atco staging lanes. The rear is super quiet and preformed flawlessly.

Good to know...thanks! I'll probably have to wait until after my next payday to get mine set-up and put back together. Christmas has kinda drained me for right now!!! But I'm definitely looking forward to it.

[ScReW]

sorry for a stupid question but i have to ask is)
i own camaro 2012 lfx wit auto transmission. in stock i have an open diff and i want to replace it with EATON Truetrack (here is link for it http://www.summitracing.com/parts/dt...ro/submodel/lt)

As i can see from website it is compatible with my diff.

But will it fit in real life?
And what parts do i need to do this replacement by myself or shop? (maybe new bearing or some seals etc. and it you have their p.n. please write them)
it's very complicated to deliver parts to my location) that's why i wish to order all of them together

Thank you in advance!

[blazzin1]

Originally Posted by ScReW

sorry for a stupid question but i have to ask is)
i own camaro 2012 lfx wit auto transmission. in stock i have an open diff and i want to replace it with EATON Truetrack (here is link for it http://www.summitracing.com/parts/dt...ro/submodel/lt)

As i can see from website it is compatible with my diff.

But will it fit in real life?
And what parts do i need to do this replacement by myself or shop? (maybe new bearing or some seals etc. and it you have their p.n. please write them)
it's very complicated to deliver parts to my location) that's why i wish to order all of them together

Thank you in advance!

If you had a manual transmission, I would say it "might" fit. From what I've heard the rear end in the manual V6 is the same as the SS, but the automatic is different. I don't think it will work for your application.