My local dealership tore down my rear differential in my 2003, 3500 Single Rear Wheel equipped with the limited slip axle today. I brought it in because it was clunking quite noticeably in first, second, and third gears, NV5600 6 speed. I assumed it was u joints, after they pulled the entire front and rear drive line they found nothing. I explained that it was worse when cornering, so they tore into the rear. Turns out the carrier was bad, caused metal shavings to wear on the ring and pinion. They are fixing the whole thing under warranty. The ring and pinion were not ruined but they agreed to replace them. Had they not replaced them the tech said they would produce a howl in as little as 10,000 miles. FYI your problems might not be u joints, mine wasn't.

ONLY 42,000 miles on the truck, lots of light towing, occasionally 15k pounds of horses and trailer.

PS- with my 45,000 maintenance looming around the corner I have a couple Q's. Does anyone of the top of their head know the size of wrench needed for the front diff cover bolts? I want to get a reversible ratchet to fit. And also does anyone know if the gaskets on the PTO cover are reusable (NV5600)?

 

So could the oil have been a factor or is this something that would have happened anyways due to defective parts?

 

Tech claims use of non mopar oil could have caused it. I was running RP75w140 which tons of people run with great success.

 

The tech would say that but I have seen a study of differential oils and Royal Purple was one of the worst performers. Some would say the study was biased I don't know one way or the other but that was one of the conclusions. I don't mean to open a can of worms but that was in the back of my mind when I saw this thread. Lots of guys run it no problems. It could have been defective parts..

 

Lots of people love royal purple. B.Law (DTR Member) said 150K miles in both diffs with no troubles. I just sent off an email to RP customer service telling them about the issue. Guess we will see what they have to say.

 

just changed out my diffs. the oil was amsoil severe gear oil-75w-90. oil had 50,000 miles on it- it looked brand new when i drained it. i probably could of gotten another 50,000 miles on that oil!

 

And also does anyone know if the gaskets on the PTO cover are reusable (NV5600)?[/QUOTE]

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The PTO covers come from the factory with silicone on the mating surfaces.

I bought a cardboard gasket from an International truck dealer and
it is reusable.
They will just want to know if it's a 4 hole or 6 hole cover.

larry

 

I wonder if GM puts Mopar oil in their 11.5" AAM axles?

I have a feeling using a non-Mopar oil didn't cause the damage.

 

I'm pretty sure they are 13mm bolts.

 

I would love to see the tech's face after that comment.

 

Probably wasn't put together correctly from the factory.

 

I seen some where on another forum they were testing lubes at a independent research firm, RP if I recall was pretty good, Torco was a exellent
product, and some beat others on differant test, but the winner was amsoil.

Just seen another on engine oil amsoil didnot fair to well, Cummins puts out a statement that no matter what type stock oil you use dino or syn you must change the oil according to schedual intervals, you do not get longer drain times just because you use syn's.

 

hope this helps

 

Excellent read.

David