Reading through the threads and posts about LSD has helped me understand only one thing, that I want to get rid of the stock LSD.

Couple questions I have though is what would be a good aftermarket LSD for someone who does about 75% city driving and 25% off-road. Unless it's hunting season then it's probably 50-50. Reading through it seemed like either you buy a LSD for City driving or off-road, nothing in between the 2.

How much does it cost on average for the set-up?

Also this truck I'm pretty sure was a repo and I have found a lot of things with it that so far have been aftermarket. It has a double bezel, aftermarket exhaust, use to have subs under the back seat, the headrest use to have DVD players in them, and I'm not too sure but with the way this thing accelerates I am thinking it has 4.56 gears. I seriously can not hit the gas, I have to slowly get on it or I am guaranteed to spin the tires. It has no level kit, just as is, stock rims on stock sized tires. So basically I am asking how in the heck do I find out if the gears on it are 4.56s? How to I find out if it already doesn't have an aftermarket LSD? Is there anything I can do or look for that will inform me that those parts are stock or indeed aftermarket?

 

( I seriously can not hit the gas, I have to slowly get on it or I am guaranteed to spin the tires ), i have the same thing happening with me , i have 2006 ram hemi its 3.92 with 20 inch wheels as the b sheet says but i bought it 8 month ago so now u made me think that is it modified or not ?? really how can we know if its 3.92 or 4.56 ??

 

haha exactly. That is what I want to know.

 

I can tell you this... mine has 3.92 gearing with 34.4" tires, limited slip, and the SC program set on 91 performance. If I hit the gas more than just a gentle push, those back tires will break loose! It has GREAT throttle response even though the gearing is for 33" tires from the factory. Is it possible your truck has been programmed with the 91 performance SC setting?

 

Anything is possible with this truck. I guess that would just add to my questions, how would I know if it was tuned?

 

man ur making me worried now , if our trucks are tuned then we r stuck with this tuning coz even if u buy a programmer it wont be able to tune it again coz u need the same device that the truck were paired with !!!!! Unless we buy new ECU hehehe

 

Not necessarily, I've been told that if is the case that it can be returned to stock setting. Not sure of the specifics but I think it has something to do like trying to determine the tune on it and contacting the manufacture and they will help you out with some kind of restore or something like that, don't count me on that, just for some reason I think I read that somewhere.

 

The old stand-by for determining gear ratio is to jack up the rear of the truck. Mark the bottom of the propeller shaft with a piece of chalk, then mark the bottom of a tire with a piece of chalk. Rotate the tire exactly one full turn and count how many revolutions the propeller shaft makes. If it turns just a hair over 3 1/2 turns, you know it has 3.55 gears and so on.

As far as the factory LSD goes, not only is it plagued with "C-Clip" issues which can be catastrophic for the rear differential, but I've found even when in perfect condition it's a sorry LSD, especially compared to the ones GM gives you as part of the Z71 package. I found that just to get it to engage properly, I had to apply a slight amount of brake with the gas or engage the e-brake slightly. I don't know what the bias is on the stocker, but I'm betting it's pretty damn low anyway.

The "track/street" guys usually opt for the Auburn because it has clutches and reacts slightly faster, yielding better launch/track times, another advantage to the Auburn is that it's also available in a "Pro" version with a very high bias, making launches even better, but it's not very "streetable". The Detroit Tru-Trac is a favorite among the off-road crowd as it doesn't have clutches that wear out over time meaning those units have to be re-built or replaced when the clutches are worn.

That said, I have an Auburn, had one in my 2nd Gen Ram and at 68k on it when I sold the truck, it worked like it did on day one. Estimated life on the clutches is about 100k miles. I have one now, mainly because of two reason. One, when I bought, Detroit had just been bought out by Eaton and the DTT for the AAM 9 1/4" axle was on nation-wide back-order. The other reason, is that Detroit at the time, would not warranty the product with tires over 33". I believe that's changed now...

 

So for 4.56 gears it should rotate just a hair over 4 1/2 revelations. That makes sense and I'll look into it.

Not sure if you saw the other posts in the thread but is there a way to find out about prior tuning for my truck? Buying it used and the way it runs I think something might be different about it that isn't stock. I'm thinking it might be the tune, or the gears, so is there a way to find out fi it's not tuned stock? If it's not stocked tuned, how do I get it back to stock tuning without having the prior tuning device that was originally used to tune the truck?

 

Only way I know for sure is to have the dealer hook the StarScan Tool up to it, it can read the name/copyright stamp revision number and date off the PCM.

Well, you can also take a Superchips to it and try to tune it, if it's not a stock tune in the SC database, it'll come back with a "Tune Not Stock" error and refuse to tune it. I had this issue on my Grand Cherokee, before SC supported the "High Output" version of the 4.7, the HO has an upgraded factory tune and the SC read it as "not stock"...