AxleIke

I have searched the forums, and haven't found what i was looking for. I wish to put a limited slip in the rear of my 4 runner, and i have been looking at the Trutrac. Who has experience with their dependability? If you could let me know how well they hold up, that would be awsome.

Also, for those who have them, i have read here that off road, the tru trac doesn't work unless you are already moving. Is this true, and if it is, and you get stopped off road, and try to get moving again, how do you get it to start working? Thanks

Glenn

What do you mean by dependable? My TruTrac's haven't failed yet, and they have been in there for several years. They do wear out eventually; I have heard they last at least 75,000 miles in the rear. Probably much longer in the front.

As far as going off road and having to be moving in order for them to work, that is incorrect. I can stop in snow and can easily have all four tires spinning if I give it too much gas when restarting. The same thing happens with mud-I can easily get all four tires throwing up a lot of mud while not moving very fast. The only reason I would do this is to clear the tire treads of mud to get better traction.

If one of your tires is in the air and has no traction, that's a different story. The tire in the air will spin. If the TruTrac is in the rear and you have a rear tire in tha air, you can overcome this problem by pulling on the parking brake a few notches to fool the TruTrac into thinking the tire in the air is actually getting traction. This takes some practice to perfect.

Roger Brown has some more info about this on his website, so you might want to check there.

Ganoid

I read somwhere that the new trutrac's are an improvment over the old with more biasing by going to a 3 gear over the older style 2 gear.

AxleIke

Well, by dependable, i was referring to how long they last, and how much abuse can they take? As far as the not working unless moving, thanks for the info. I am trying to increase traction with wheels off of the ground, so if the limited slip does not work for this case, then perhaps i need to consider waiting for a locker.

Do these new three gears work better when a tire is off of the ground?

Glenn

I think a TruTrac costs more than some lockers do.

AxleIke

Here is my Dilemma. I want more traction. Obviously, the TruTrac will give me some, as much as a Limited Slip can, and the other option is a selectable locker. A locker is way expensive, and a limited slip will be an easier install, although that isn't really a consideration. I guess the remaining question i have is: In the event of a tire off of the ground, will the TruTrac help at all with traction over an open diff, or no? Thanks guys.

EnolaGaia

Basically - No. If the situation you're worried about is having one wheel off the ground, an LSD is no real improvement at all.

4Crawler

iTrader: (3)

A TruTrac can be locked up with application of brake biasing. It takes a while to get the hang of the technique, but it does work:

http://www.4crawler.com/4x4/TrueTrac.shtml

You can see a tire in the air in the photo below and it is not spinning any faster than the tire on the ground:

Blizzard

And why not going to an auto locker? They're cheaper than an LSD and lots cheaper than a selectable...

I've a Detroit Soft Locker in the rear and an Aussie Locker in front and they're great!

My 4Runner is my DD and I got used to the locker pretty fast, now I don't think in the Detroit, my foot do for itself! Only chirp tires in upwards closed turns...

David

AxleIke

So, i read the part about the brake biasing, and that sounds like with some practice it would work well. However, the question i had was do you have to keep the brakes on all the time while the wheel is in the air, or is just a start all i need. For instance. Lets say i was climbing a hill, and encountered an obstacle where a tire was lifting. I lose traction and i stop. Could i pull my ebrake (the Trutrac will be in the rear) a few notches, get the wheels started, and then let it off, or would i need to keep it on through the entire hill. I'm worried that if i don't have enough practice, i'll just burn up my brakes. Thanks

AxleIke

Becasue i live where there is lots of snow and ice, and i'm not comfortable enough with my driving skill to get a soft locker. Plus, i don't like the idea of all that noise.

Glenn

You just keep the brake on until you get the tire in the air back down on the ground. Keeping it on all the time is not a good idea.

AxleIke

I don't mean on all the time, but you did answer my question, i think. I was refering to whether i needed to keep the brake on until my tire got back on the ground, or whether an ebrake start would suffice to kick it in, and keep it in, and i could let the brake off. So, for instance, could i be stuck with my tire off of the ground, pull the brake, let out the clutch with some extra gas, and then let off the ebrake, (ebrake start), or would i have to click the brake on a few notches and ride through the whole obstacle with it on? Thanks all of you, i really appreciate the help.

I don't want to heat up my brakes, and i'm concerned about engine power on the hill, so that's why i'm asking.

4Crawler

iTrader: (3)

Brakes need to be applied any time a wheel lacks traction and spins. The amount of braking force depends on how much torque you need to move. Rough idea is about as much brakes as it would take to hold you in place on the obstacle. Usually not a problem w/ heat, you are usually only going very slow when you need to brake bias. You need to be in a very low gear to make it work well, practice makes perfect.

AxleIke

Great! Thanks for the info. Do any of you know if there is a 3 helical geared TruTrac, and if there is, is it better than the 2 geared one?

I know you probably have 2 cases with 4.7's, in one, and 2.25(sorry spacing on the exact stock ratio) in the other, but my budget hasn't allowed me to go there yet. Will stock Lo 4 work with it in First? Thanks

4Crawler

iTrader: (3)

I found about 75:1 crawl ratio worked the best to work the TT. It can probably be worked at smaller ratios (stock is around 40:1) on milder obstacles. You have to practice the technique with what you have, know when and how to use it. I never quite got the hang of it with stock gears, but later with lower gears, I picked up the technique and just stuck with what worked.

elripster

I broke my rear truetrac using the brake biasing technique. It certainly works, in fact crank on the e-brake and it basically spools the rear end. However, not only can this break the TT but the torque on the axle shaft can twist it. (did this too when I broke it) I've heard of others having similar problems.

To sum it up, TT's a great for moderate off roading. Rock crawling or similar is not recommended.

Frank

Blizzard

Ahhh ok. About the noise, no noise with the soft locker, maybe sometimes when parking. With the Aussie I have 0 noises.

David

jaymo

I have a detroit locker in the back and it hardly makes noise and has 120000 miles on it. Now about the true track, I also had it up front and ended up breaking it on double whammi a few years back. I am not sure about longevety of the the tt,but the locker is indestructable(so far). Hope it helped...Jay....

Napoleon047

i have a truetrac in the front of my rig. before i put the 4.7:1 gearset in, i had to have the engine wound up pretty high to do the brake biasing, otherwise it would stall the engine. its to the point that im about ready to put a lunchbox locker in the front now too.