2006 1500 Mega Cab 4x4 with the dreaded rear end noise....from what I've here it will need gone through and rebuilding. Plan on taking it to the dealership...anyone had one done lately and can tell me an approximate costs?

thanks in advance
griff

 

You don't hear of the AAM 10.5 (or 11.5 for that matter) failing very often. Actually, aside from the "c-clip" caused issue, you don't hear of too many 9 1/4" rears go either provided the fluids are changed at or around 30k as recommended.

Had a guy around here a few months ago was quoted around $2600 at the dealership for a 9.25" rebuild at his dealership.

Personally, the dealer would be the LAST place I'd bring it, as stated these axles don't fail too often and you'd be hard pressed to find a good axle guy working at the dealerships. I'd bring it to a good axle shop or 4x4 lift shop who normally has a good "gear man" on staff. You'll cut your cost by 50% or more and probably end up with better work too.

As an example, per axle the local dealer here charges $1450 for a ring & pinion swap (parts & labor) and my local 4x4 shop charges $600 or at least did as of a year and a half ago. I've sent half a dozen guys to the 4x4 shop and have yet to hear one come out of there with a hint of a whine...

 

I may be confused here....I'm thinking, from what I've read, that only the pinion gear will need replacing and the clearance setup. All I have is a "whine" and nothing major has failed that I'm aware of.

The price you stated "$2500" is that for a total rear end rebuild or just pinion gear c/o?

 

If it's just a whine then you probably wouldn't need a total rebuild, just the ring/pinion and a master kit (bearings). Have you checked the condition of the fluid? How many miles since the last fluid change? What's the wear pattern look like? That should tell you exactly what you'll need. Hell, I've heard them whine like hell and shut up because they were badly in need of new fluid...

 

I actually just purchased the truck...it has 145k. Not sure if the fluid has ever been changed.....hell it could be just low. Maybe I need to just change it and see if that helps. I remember reading something about an "additive" needed for the rear end fluid....do you know anything about that?

 

Oh ok, then yeah you really need to drop the cover and look. Could very possibly be neglect by the PO, but you can spot a bad gearset in a heartbeat. You know what a proper set of gears that aren't grinding on each other should look like even if you've never seen the inside of a differential before.

Only way to tell is by looking.

NO, you do not need limited slip additive with a 2500 rear end. If equipped with a LSD, unlike the 9 1/4" rear (non MegaCab 1500s) which has clutches, the 2500 is a gear-type of LSD (think Detroit TruTrac) and requires no friction modifier (additive)...

 

I pulled the cover today for inspection, the lube was filthy black, probably had never been changed. Considering the oil condition nothing looking out of the ordinary. No major metal findings just some metal flakes/shavings (very minor) which I believe are okay. The gears appeared to be in good shape and have normal wear with nothing really noticeable.

I buttoned her back up and refilled with RP 75w-90. Took her for a test drive...the whine is considerably better but still a little noticeable when getting off the gas pedal when running around 45-55mph.

I guess I'll see if it gets any better. I'm definitely going to do the front also along with changing all the fluids.

thanks for the help,
griff04

 

If the rear ends (save the c-clip posi) are as durable as stated above, go to a salvage yard and find a replacement for $3-500.

 

Or just leave well enough alone and keep driving it.

 

Megas don't have the c-clip(actually w-shaped retaining clips) issue that plague the Light duty 9.25" diffs.
Megas along with 2500/3500's(10.5+ sized diffs) have worm type gears, so there's no retaining clip problem to deal with.

I would say you have a worn pinion bearing which changes the contact pattern of the ring/pinion and causes the slight whine. If the oil was as black as you say, I'd suggest changing it out once again to flush it out, If you plan to just drive it. The oil tends to stick to the inside of the case and parts, plus there is still oil in the axle tubes when you drained which doesn't drain and can only be flushed out or pushed out through the axle tubes(which requires removal of the axles) Or leaving your truck jacked up on each side for several hours so it can very slowly drain out through the bearing races.