This question was inspired by some dealership BS and some curiosity. I have already attempeted to research it and had no success, which, was dissapointing seeing as this information should be easy to find.
Recently, my boyfriend's truck started to act funny. It's a 2003 Hemi 2500 4x4 with about 60,000 miles on it. All service has been kept up, so that shouldn't be a factor. He started to complain that the posi trac wasn't working like it should. He also said it made some noise and crap, etc. So he brought it to the dealership since it's still under warranty. They opened the rear end up and found that the clutch for the posi trac was stripped, or something like that. The dealership kept the truck and began the BS.
First it took a week for them to just tell him that the part that the rear end needed wasn't going to be there for another week. His only other car to drive (without getting a rental,and courtesy car was unavailable because he's under 21) is a 73 Javelin which is nice, but not practical for him for daily driving. Finally, they get the part and put it in. Posi trac is again, acting as it should.
We began to ponder on how exactly the Dodge rear end w/posi trac works. We looked for diagrams or information on the company that might make them. I understand that ther ARE several types of the posi trac, but I'm curious, now to know how it does work.
Needless to say, he just called me and said that oil was on the ground under the rear end and that they screwed something up when they put the bolts back on. Yet another trip to the dealership is scheduled....
Anyways, if anyone has any information on this rear end w/ positive traction, let me know!

 

well a while back i too had a noise coming from the rear end. at first i thought it was the brakes making the noise, so i brought it in to get the brakes checked. when they heard the noise they instantly said that it was the posi trac. for those who dont know, with posi trac you need to add a special lube along with the oil when you change it out. guess what, when i got it serviced, they either forgot or they didnt know to put it in- idiots. you would think that they are smarter than that since they frickin do it every day.
well without this lube, you could do some serious damage. luckily i caught it in time and saved the rear end. your boyfriend may have had this same problem.

 

Check out this link. Some useful info there as well as some pretty neat animation. Sounds like you need to find a new dealer btw. Best of luck

 

darrinvw02

I wouldn't be so sure that you caught the trouble with your rear end in time, let me relate to you a horror story that I had with mine.

At 15,000 miles I noticed my rear end had a slight leak around the pinion seal, and since it was time for the lubricant to be changed anyway (I tow a trailer a good bit and therefore use schedule "B" for maintenance) I took it to a local dealer to have this done. They replaced the pinion seal and changed my lubricant. After driving another 4000 miles my rear end began to make a nice humming sound and I took it back to the dealer for repair. At this juncture they replaced the ring and pinion gears along with the side bearings.

Getting a little suspicious I made a special point to inquire as to whether or not they had used the proper lubes upon making this repair. The service manager assured me that they had replaced it with the proper synthetic oil and used the special anti-slip additive. Because I was still suspicious I checked the invoice, where they had changed it the first time, and found that they had used the wrong lubricant, the part number listed was not a Dodge part number and they listed only one lubricant which indicated to me that the anti-spin additive was not used. I also checked the part numbers of the two lubricants that they used when the gears were replaced and found that they were correct. I knew they were good Dodge part numbers so I posted them in this forum and received word that it was the correct lubes.

Case over, well not quite. I drove the truck about 400 miles and then, with my travel trailer in tow I headed out for a camping trip getting only 80 miles down the road before my warning lights came on, followed shortly thereafter by my speedometer failing. Pulling off the interstate I quickly discovered that my rear end was making a strange noise and was very hot to the point of smoking. I did make it to the local Dodge dealer in that town which, luckily enough, was only about 3 more miles down the road. After inspecting the rear end the service manager told me that he thought it was a total loss and would have to order a new rear end for it. One week later I picked the truck up and it now has a completely new rear end, axles, housing and all.

Best guess is that the dealer using the wrong lubricant at the first repair probably ruined all the gears and they only replaced the ones that were in the worst shape. So if I were you, I wouldn't be so sure that you have gotten away with them using the wrong lubricant when they changed it, if it was making a noise chances are it's going to bite the dust on you somewhere down the road, hopefully not before the warranty expires.

This served as a reminder for something that I already knew, and that is the fact that there are dealers out there that don't know their rear ends from a hole in the ground. Don't trust them for anything that you can verify yourself or have verified. If you get suspicious about something, you may very well be right, check it out, this board is a good place to start.

 

Damn...that is a horror story. Makes me glad I change my own. I know the stuff's in there then.

 

mill500

You can bet that I'll personally do it next time, I don't allow anyone under my hood unless it's something that I absolutely cannot do for myself. I shudder to think what this would have cost if it had not still been in warranty, the parts by theirself were $1,391.25.

 

Actually, unless he has a locker or some sort or aftermarket installation (which would have voided the warranty), it's called limited slip. Since you said there are clutches I'm about 90% sure it's a LSD. It does need a special additive put in as well. LSD (limited slip differentials) have clutches in them that wear out espically if it's used for towing or hot rodding. 60k on a limited slip is pretty good. Sounds like they did mess something up when they repaired it though.

Next time it wears out which then it should be out of warranty, upgrade to a locker or aftermarket LSD like Powertrax or something. Check out their web site and look at the video. There is one with a stock Dodge diesel LSD vs. the Powertrax in an old 1970 Ford. Very eye-opening.