well this is how i see it, a lsd is already an option for our trucks so i doubt that we will lose esp if we add an aftermarket one. the esp senses the wheel spin of the rear tires both against eachother and against actual ground speed to determine how to apply itself. Also I would be willing to lose the esp program if thats what it takes to get a lsd for my 3.55 rear end since i hate the esp program anyways. On another note, if we do install a lsd diff then all we would be doing is reducing the wheel speed difference between the two wheels so in theory the esp would not engage as much since both wheels will be spinning the same speed. It would only kick in when it senses the wheel speed is much greater than actual ground speed.

 

For what it's worth, my '09 SLT Quad, 5.7L Hemi came with a 3.21 rear end.
It works for me!!
Jack

 

I have the 3.92 axle, it works great, however gas mileage sucks. I get an average of 15 with the hemi. I believe that my rpm's are around 2300 at 70. At 60 I am getting 18.5 and at 70 16.7 mpg, however it's a truck with 390 HP?? so can't complain.

 

Yea I get about what you get, maybe a little more. I still like the off the line acceleration you get with the 3.92's, after 7 months of ownership I'm still impressed with it................Kevin.

 

Sorry I mean out of business at least I think a plant in Detroit closed.(packed it in)

 

.....

 

3.92 here and the mileage is about 3mpg lower than my 06 RAM.... I'm guessing 3.55 in that one... guess I'll slow down on the highway.... but at least I can floor it to get up to speed. :-)

 

I think it is the 31-spline, but don't consider this a final confirmation.
Does anyone recommend any exact Auburn LSD model? Is the Mopar LSD the factory LSD for the 3.92? Does an Auburn LSD need differential oil friction modifiers or any kind of additive, or would that all be specific to each model/technology? I think my truck has the 3.21 rear, it runs at 60 mph @ ~1600 RPM. If I drive as slow as I can in top gear (~56 mph) I get about 18.5 mpg. I speed up before a hill so as to avoid downshifts.

 

dswan: I'm pretty sure you have the 3.55 axle since that is what I have and i run around 1600 at 60 mph also. And yes some clutch type lsd do require a friction modifier, that is why you should get the work done at a place that knows what they are doing. And auburn or eaton is the way to go since they both make very good lsd models. I'm about 60% sure that we have the 31 spline axle but I would just like to confirm with someone who knows for sure that it is right.

 

Totally agree with you, as I drive a Sprinter Diesel, and when I get in this thing, I snap my own neck...along with others too.....lol