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Atom
April 15th, 2004, 19:59
I have a line on some Detroit TrueTrac lockers, but I dont know anything about them. Maybe someone can help me with these questions:
1. Is the true track a cluch or gear locker and how agressive is it?
2. How well do they work in an xj with out locking out hubs
3. How does the true tack work?
Thanks for the help!

Eagle
April 15th, 2004, 20:17
First, a TrueTrac is a limited slip unit, it isn't a locker. It's gear-operated, no clutches. It's more aggressive than a factory Trac-Lok limited slip, but doesn't always lock up the way an automatic locker does. I believe the manufacturer only warrants it for use with up to 32" tires.

It is a full carrier unit, not a "drop-in" that uses the OEM carrier, which means the gears should be re-set when installing.

rngrfrd2000
April 15th, 2004, 20:18
automaticlly lock when needed..i have one in the rear on a dana 35 with 32's and i love it...you may have to adjust your driving a little bit when cornering but on the trail they rock the rocks man....i think it was the best upgrade i have done and if you couldn't tell i highly recommend them

Atom
April 15th, 2004, 20:23
Eagle- since the factory only gives them a one year warantee should I stay away from these used ones? They have about 40K and are from a mild wheeler who upgraded to ARBs. I would like ARB's too but cant afford them right now. Also I am planning on regearing to 4.56's so since I was regrearing anyhow I though why not add some traction.
But I do want to put 33's on next, what would you suggest?

Eagle
April 15th, 2004, 21:15
In theory, since a TrueTrac is gear driven there should be nothing to wear out. In theory.

I run a TrueTrac in the '88 MJ with 31s. It is definitely more aggressive than the factory Trac-Loks ... the MJ chirps everytime I drive over the lip exiting my driveway, the XJ doesn't and the other MJ with Trac-Lok doesn't. To me except for the occasional chirp on tight corners on pavement it is totally transparent, but I've been driving on limited slip diffs for more than 40 years. I don't run one in the front but I have friends (which may surprise Beezil) who do and they're happy with the street manners.

I wouldn't be afraid of a used on if the price is right. I think they go for around $350 to $375 new (???), and a Trac-Lok new goes for around $250. I don't think you should pay more than $200 (maybe $250) for a used one with that many miles on it. I've had mine in for three or four years and I'm not close to that mileage.

Gojeep
April 16th, 2004, 02:16
Have front and rear and they have been great. Good for towing duties to and side slopes which cant be said for lockers.

poppabear
April 16th, 2004, 06:54
got one in front and its invisible on the street... great option for the front. got mine used with about 10k miles on it.. 170 bucks... couldn't pass it up.

Nay
April 16th, 2004, 07:56
Have front and rear and they have been great. Good for towing duties to and side slopes which cant be said for lockers.

What is the difference on side slopes? Unless the true trac is allowing slip, it will act just like a locker in a straight line. I've run both, and allowing a sudden spin of one tire on a side slope is about the worst thing that can happen (unpredictable and sudden loss of traction), and limited slips sometimes allow this to happen while lockers don't.

I used to run front and rear limited slips, and I think it is an ideal combo for moderate XJ's. However, the Detroit locker in the rear I have now is a lot more predictable than a limited slip, and it is fine on side slopes. I'd never choose a limited slip over a locker for the concept that the locker is dangerous on side slopes...simply doesn't play out in reality.

Nay

Goatman
April 16th, 2004, 10:05
Eagle- since the factory only gives them a one year warantee should I stay away from these used ones? They have about 40K and are from a mild wheeler who upgraded to ARBs. I would like ARB's too but cant afford them right now. Also I am planning on regearing to 4.56's so since I was regrearing anyhow I though why not add some traction.
But I do want to put 33's on next, what would you suggest?

If you're thinking lockers and 33's, and would really like to have an ARB, you will be wasting your time and money on a TrueTrac for the rear. They don't work like a locker, but are a good limited slip, so if a locker is what you really want, you'll probably be disappointed. Also, the TrueTrac is not recommended for 33" tires, and is not recommended for use in the rear. Jeff Turner broke his rear TrueTrac a couple of years ago on Rusty Nail in Moab running 32's.....that was another get home in the dark run on Spike.

Wait to here from a few more who ran them and now run lockers, rather than a few who run them now. It's always hard to know the background when considering this kind of advice, because you don't know the type of wheeling, and the expectations, of the people sharing their experinces. BTW, it would be better if people included some background when responding to a question like this, so the response can be put into context. I'll agree that two
TrueTracs are a great combination for smaller tires and moderate wheeling on a regularly street driven rig. Moderate wheeling, BTW, can include some difficult trails, like the Rubicon and nearly all trails in Moab. But, if you'll end up wanting a bigger tire, and doing trails that require lockers, then the TrueTrac isn't the right choice.

Atl XJ
April 16th, 2004, 10:48
I've searched everywhere and I can't find an answer. Do they make a truetrack for the 8.25? I have the 27 spline. Sorry for the hijack. :dunce:

Eagle
April 16th, 2004, 11:10
Also, the TrueTrac is not recommended for 33" tires, and is not recommended for use in the rear.

???????

Huh? I've already posted that it's not warranted if used with larger than 32" tires, but whoever said it's not recommended for use in the rear? First time I've ever heard that. It's sold for use in the rear, and I'm sure I'm not the only person in the world running it in the rear.

Also, FWIW, although TracTech says it isn't wanrranted when used with tires larger than 32", everything I've read indicates they will replace it if you break it with 33s

ChiXJeff
April 16th, 2004, 12:25
I've searched everywhere and I can't find an answer. Do they make a truetrack for the 8.25? I have the 27 spline. Sorry for the hijack. :dunce:
You're pretty limited in choices for a 27 spline 8.25 axle. For limited slips, probably an Auburn High Performance (http://www.auburngear.com). Locker? Full Detroit, but there is a lunch box locker available which eludes me at the moment. Or an ARB air locker.

TracTech (http://www.tractech.com) only shows a full Detroit for the 8.25 axle. It's also interesting that they don't show an ElecTrac for a D30 either, I thought those were out.

Atl XJ
April 16th, 2004, 12:28
Thanks for the info. I know you can get the tracklock and the noslip for it too, but I was thinking about the truetrack since its more streetable and its my DD. I'd love an ARB, but they are too expensive. Thanks, I'll check out those links.

ChiXJeff
April 16th, 2004, 12:43
Thanks for the info. I know you can get the tracklock and the noslip for it too, but I was thinking about the truetrack since its more streetable and its my DD. I'd love an ARB, but they are too expensive. Thanks, I'll check out those links.
FWIW, I run an Auburn HP in my 8.25, and a TrueTrac in my D30 in my daily driver.

Aside from having to change the gear lube in the Auburn pretty frequently (4 times per year,) this is a good combo for a daily driver.

Nay
April 16th, 2004, 13:08
Thanks for the info. I know you can get the tracklock and the noslip for it too, but I was thinking about the truetrack since its more streetable and its my DD. I'd love an ARB, but they are too expensive. Thanks, I'll check out those links.

I used to run the exact same combo ChiJeff runs (I think I even talked him into it) when my XJ was my main tranportation. Get the Auburn for the rear - it is strength rated near a full Detroit. I wheeled the "difficult" trails in Colorado and Moab with this setup...trails we now consider moderate. With good flex, I could do a lot...and certainly everything the guys with just rear lockers could do, but nothing even close to the "extreme" trails we see these days. Onroad it was very nice, and good in bad weather.

I do think that you need to think about the long term, which is what Richard was pointing out. It doesn't seem like many of us "sit still" and are content to run the same level of trails forever, and you can quickly get to the point where limited slips aren't much more useful than open diffs. These are full carrier replacements, which makes them much more expensive than lunchbox lockers unless you can do sophisticated diff installs yourself.

I resisted doing an automatic rear locker on my daily driver for years because I was so concerned about behavior. An automatic transmission really does tame an automatic locker. If I were spending the money for a full carrier install, I'd be putting in a Detroit. For the rear, I would choose the Detroit over an ARB money not withstanding (and I did), because I like having it back there all the time, automatically. It is a balance between driving in potentially severe weather in the Colorado high country and wheeling in the desert.

Bottom line: you should find somebody in your area with a rear locker and drive it. Make your decision from experience. This costs nothing and will tell you everything you need to know vs. spending a lot of money and discovering that what you needed to know was the opposite of what you spent your hard earned cash implementing.

Nay

basalt51
April 16th, 2004, 22:28
I'm with Nay on this one. If you're paying $400-$500 for both truetracs, just put a new detroit in the rear when you regear. It'll be much more realiable and give you 100% traction, not 90% traction till you really need it then 0%. Then when you decide you want something in the front get a no-slip or lockright that you can easily install yourself. I thought autolockers were the worst things ever on the road and I should never get one (opinion entirely based on second hand info). Well thats crap, I got detroits front and rear now since the new axles came with them and they are hardly noticable and the traction is AMAZING!!! Onroad I know when the rear is going to lock up (when I give it a good amount of gas around a sharp slow turn) and otherwise it doesn't make a sound. I didn't really realize the difference they were making until this weekend. I crept up and over one pretty big obstacle without the slightest effort and didn't think anything of it till an open CJ with 36s tried the same line I did and couldn't even get started up the rocks. He got opposite tires on the first two rocks and was done!

Of course you'll see alot more ice than me, but the difference in the ice between the truetrac and the full locker probably isn't much.

Handlebars
April 17th, 2004, 07:27
I've had front and rear TureTracs in my XJ for about 3 years and 50,000 miles. They are perfect for my wheeling style. I don't do hardcore trails and never plan to. They can lock up an airborne tire, but you have to tap the brake while it is spinning in order to get the differerntial to engage. This can be a challange sometimes, as I have a 5 speed but I think I have finally mastered it. :)

http://www.fototime.com/EF167FF9D60E244/standard.jpg

Traction isn't what limits me from the tough stuff, it is the lack of low gears that hampers me when the trail gets really technical. I have 33 inch tires and have blown up the rear TrueTrac once. That happened within 1000 miles if it being installed. I think it was a manufacturer's defect. One of the snap rings holding the worm gears in the differerntial case came out. The replacement has lived just fine for 50k miles since then. They warranteed it, although they did try talk me into upgrading to a Detriot Locker.

XJEEPER
April 17th, 2004, 08:06
Also, the TrueTrac is not recommended for 33" tires, and is not recommended for use in the rear. Jeff Turner broke his rear TrueTrac a couple of years ago on Rusty Nail in Moab running 32's.....


Not to mention driving 270 miles home in front wheel drive......."I can't drive 55!"

While I did break a TrueTrac that was only 2 months old while running 32's, it had nothing to do with the tire size or abuse. After Detroit warranteed the TrueTrac, I discovered that my D35 housing was shaped like a boomerang, which caused abnormal stresses to be constantly applied to the gears inside the TT unit.
I'd run one again in a heartbeat if the rig was for daily driving with occasional moderate to hard wheeling......hey, I did Pritchett Canyon with it the day before it came apart on Rusty Nail. I'd have one in my M20 rear if they offered it, but the Auburn ProSeries unit works pretty well too for the daily driver and moderate wheeling stuff.

Your best bet is an ELocker, ARB or OX if you want selectability......... more money? Yes, but the longterm investment is worth it.........I wouldn't recommend any of these for a D35 rear, poor ROI.

rj454
April 17th, 2004, 08:22
I have a line on some Detroit TrueTrac lockers, but I dont know anything about them. Maybe someone can help me with these questions:
1. Is the true track a cluch or gear locker and how agressive is it?
2. How well do they work in an xj with out locking out hubs
3. How does the true tack work?
Thanks for the help!

I'd be interested in one for a D30, if there's extras. How much are you paying? PM me if I can get one. Thx- RJ