I was looking at getting a positraction differrential for my 1999 5.2 Durango. I dont know much about differentials so i was wondering if anyone would recommend a certain type. Thanks.

 

Well first of all, what do you use your truck for most often?

There are a few types of "positraction" differentials. There are limited slip differentials, lockers and spools. I'm going to guess you don't want a spool!

Limited slip differentials are built similar to open differentials but have clutch packs to control the torque split between the two wheels. If your truck never really sees any offroad use, it is all you really need on road because they still allow the wheels to differentiate under power.

Lockers are a different animal. Most of the work where they lock up to a 50-50 power split while under load and unlock when there is no load present. This allows the wheels to differentiate through a turn as long as you don't have too heavy of a foot on the gas pedal. If you are pressing the gas pedal too hard, for example, turning right from a stop sign or traffic light, you can easily lock up the locker and cause one wheel to be pulled through the turn, causing accelerated tire wear. These are much better for offroad use because if you got in a situation where one wheel was completely off the ground, the other wheel would get power, whereas most limited slip differentials would slip.

If all you want is a limited slip diff, the easiest thing for you to do is to find one in a junkyard and swap the entire axle assembly! This will prevent you from having to re-set the carrier bearing preload and ring gear backlash.

If you want a locker, they make "lunchbox lockers" like the powertrax no-slip that replace the guts of an open differential case so you can install them without removing the carrier and again avoid setting bearing preload and backlash.

If you aren't opposed to getting in that deep with a differential install, or don't mind paying someone else to do it, there are several other options for aftermarket LSD units like Auburn Gear Differentials and full lockers like Detriot lockers, but its debatable as to how much better or stronger they really are.

 

mainly just daily driving, but i occasionally race and do some off-roadin and its a biatch to get going off the start and nearly impossible when theres water or ice on the road. That wheel just spins and spins. Thanks. I think im gonna go with a limited slip differential. Ive heard there are different sizes, if heard of 8.25, 8.25 dropout, 9.25, 9.25 AAM. What do they mean?

 

Well there are two axles Dodge used on the Dakotas (I don't know if both were used on the Durangos as well)... the corporate 8.25" and corp. 9.25". I've never heard of "dropout" or "AAM", so I don't know what to tell you. Just look for a differential carrier for a Chrysler 8.25 (if you have a 10 bolt oval diff cover) or Chrysler 9.25 (if you have an octagonal 12 bolt cover).

 

Thanks for the info. I got a 8.25 10 bolt.

 

There are 2 different axles.

8.25 Open 355 gearing only.

9.25 Open and LS with 392 gearing and also 355 from what I understand.

Also the 9.25 also came with a Track-Loc Limited Slip as an option. It was available in 392 gearing only.

If you want to swap out then you need to ensure that you have 392 gearing in the front and a 9.25" corporate axle in the back then get a 9.25 LS rear end and you would also have to change out the pinion from the donor, if you want a clean swap over.

Also you can swap out the LS clutch pack for a posi if you want.

 

yes hydra, the 9.25 rear DID come with 3.55s in it (ask me how i know, PLEASE!!!!!! )

and everything hyrda said is 100% correct

 

+1, the 9.25" came with 3.55s. I know this because the rear axle under my '95 Dakota came out of a 2001 Durango. I put a trac-lok in it, so now I have 3.55 LS.

But just to add to hyrdashockers comment, you don't have to have a 9.25" in the back from the factory!! You do have to match the gearing, but you can put a 9.25" in there to replace the smaller and weaker 8.25". Its a direct swap. Obviosly though, if hyrdashocker is right and the 8.25 was only 3.55, and the 9.25 only came with the trac lok as an option with 3.92s, then you will need to grab both the front and rear axles and swap them both to have the same ratio and get the LSD.

 

Man it's fun to rack your brain 95.....LOL


Why however do you think it never could come with a 9.25 from factory??????

 

I don't understand the question. The OP said his differential was a 8.25" in post #5.