Rear Differential Question

[RWFoote]

Hello all,



I went to the local Dodge dealer to have my 15K front and rear differential fluid changed. The young lube tech was very nice and showed me around under the truck until the Service Manager said OSHA would shut them down if "civilians" are in the shop area.



Anyway, when I got home I crawled under to lube the front drive shaft fitting. The Dealer said (again) there is no fitting and drive until it fails. Yeah, Yeah Yeah. Fortunately, TDR Magazine and the forum has educated us otherwise.



So after 20 minutes, I noticed fluid weeping/dripping from the rear differential plug. In fact, you could see the threads on the plug. The guy forgot to tighten the plug. So I got out my 3/8 " drive and tightened the plug until it was snug and not weeping.



I figured there must still be enough fluid in the rear diff to be OK since it was still weeping and I didnt want to get the nice young guy in trouble with the Service Manager. So my question is, is there a torque specification for the front and rear differential plugs?



Thanks again for all the good advice.



I will probably do Mag-Hytecs at 30K.



Bob



2007 Dodge 3500 5. 9L 48re, SRW, Quad, Lance Camper hauler.

 

[jdbecker2]

Fill plug torque is 24 ft lbs The differential cover bolts are 30 ft lbs if you want to check those too. Might not be a bad idea just to do the job again if you think you lost too much oil...

 

[Wingate]

The dealerships around here don't even pull the covers. The stick a vacuum hose down the fill port and suck the oil out.

Personally, I don't like this procedure. I prefer the longer method of removing the cover, wiping out any remaining oil and "gear ooze". Besides, it gives me a chance to inspect the differential for any signs of wear.

If you check/remove the differential bolts... Seems like I remember readingon here that the cover bolts have a tendency to break... You might do a search on it. .

 

[HBarlow]

I normally carefully follow the manufacturer's service schedule but when I learned that Gen III Rams are supposed to have the differentials serviced at 15k miles I stubbornly refused.

I installed a Mag Hytec cover (2wd) on the differential when the truck had only a few hundred miles on the odometer and changed the lube at 50k mile intervals. The rear end was still strong and quiet at 230k when I sold the truck.

I wonder whether the differentials truly require new lube at 15k or Dodge dealers truly need the service department revenue?

 

[MickeyMiller]

I'm with Harvey... 15K diff oil changes is WAY excessive. I did a early change of all lubricants (diff's, t-case, engine, and trans) at 1K, did the original 15K change but the oil looked new. I'm now on a 25K schedule and think that's more often than needed... Royal Purple is still clean and purple! But I don't carry heavy loads often, maybe a couple of times per change, but do do a lot of mountain driving. 120K so far, no problems!

 

[WCounts]

Yes they do need the oil changed often on the AAM TracRite differentials. They don't have clutches and the Worm gears bind the housing metal to metal. This puts metal particules in the oil.

Billy

 

[MMeier]

Hello all,



I went to the local Dodge dealer to have my 15K front and rear differential fluid changed. Yeah, Yeah Yeah. Fortunately, TDR Magazine and the forum has educated us otherwise.

Sooooooo... why did you go there??!!

 

[DGamelin]

If you have a posi the changes are necessary. I didn't think so when I pulled my cover off for the first time at 55k it was full of metal fillings. The type of posi they use, uses helix gears when it locks up it is under compression metal to metal. That lends itself to very small fillings. The posi had to be replaced. I checked to see if there was a plate type I could put in or the same in a detroit locker and there wasn't at the time. So I had it done by the dealer why pay for a stock posi. I changed the fluid at 70k just last week and full of filings again. Every 2500 miles I take the fill plug out and clean the metal filings off the magnet. I do pull big loads a lot. Make sure you have the right fill level. Mine is about 1" below the hole, the cover has a line on it. Over fill can lead to foaming.



93 250 2wd xc 354 auto 255k

04. 5 3500 4wd cc dully 373 6speed 70k

 

[WCounts]

That's why I run cheaper dino GL-5 and change it often. You just can't leave the expensive synthectics in there long enough.

Billy

 

[DGamelin]

Bill , I think your right. If it wouldn't have taken me an hour and a half to put the pictures on I would have seen your post six, you hit it right on the head. I find these posis disappointing. They don't work in the snow at all. They're fine in the mud and it seems any where else.

I like the numbers your truck turns.

 

[WCounts]

Bill , I think your right. If it wouldn't have taken me an hour and a half to put the pictures on I would have seen your post six, you hit it right on the head. I find these posis disappointing. They don't work in the snow at all. They're fine in the mud and it seems any where else.

I like the numbers your truck turns.

They don't lock up like some posis do but I have found they work better with oils that don't contain friction modifiers.

#ad


Here's a pic of mine.

Billy

 

[steved]

I have 80k on my fluid and there is no residue like you posted, nor any metal on the magnet. FWIW.

And they are not metal-to-metal... look at the FSM diagram, there is a clutch in them called a "brake shoe"...

 

[steved]

With that much residue, I would be concerned you have something slowly failing... I have 180k on my truck, with some towing, and the fluid has never looked like that.



Just my opinion...

 

[ColemanR]

My truck is at 295k. 250kplus its had a 26ft trailer behind it change it every 50k its never looked like that. That looks kinda scary to me. Randy

 

[ColemanR]

After my first post I got to thinking do you do a lot of in town driving what I am thinking is if you do a lot of turning maybe thats why most of mine is freeway it just seems like a lot of residue. Randy

 

[Regcabguy]

Diffs.

My rear diff fluid would have "gagged a maggot" @ 9200 miles. It was jet black and stunk to high heaven. Very little metal particle residue though,so maybe that's the way they're suppposed to look and smell. I installed a Mag-Hytec and Amsoil Severe gear 75-90 and it's gonna be in there for awhile.

 

[DGamelin]

Mine see almost all highway driving, I run from MI to TX once a month I usually run down empty and bring back a goosenecks loaded with tractors or trailers. Then the truck sits until next month unless something has to be moved. The first posi worm gears were so loose you could rattle them around with your fingers. The new posi is on its way to doing the same thing judging by the look of the oil. If this one goes I will use a after market one, I want to change to 4. 10 anyways.

 

[rbattelle]

Fill plug torque is 24 ft lbs The differential cover bolts are 30 ft lbs if you want to check those too. Might not be a bad idea just to do the job again if you think you lost too much oil...

That is the spec, but it's WAY too high. I torque to no more than 20 ft-lb. Last few times I did the job I torqued to "snug".

With that much residue, I would be concerned you have something slowly failing... I have 180k on my truck, with some towing, and the fluid has never looked like that.

I agree with steve; something isn't right. It looks like you've got burn marks on some of the ring gear teeth. Or is that just oil drips?



What oil are you using? Fill level should be 1/2" below the fill hole +/- 1/2 inch. I fill to the bottom of the fill hole.



Are the tires on the left and right sides of your truck the same diameter?



Ryan

 

[steved]

My rear diff fluid would have "gagged a maggot" @ 9200 miles. It was jet black and stunk to high heaven. Very little metal particle residue though,so maybe that's the way they're suppposed to look and smell. I installed a Mag-Hytec and Amsoil Severe gear 75-90 and it's gonna be in there for awhile.

That "stink" is the sulfur component of the anti-wear additives... not necessarily a bad thing.

 

[steved]

If this one goes I will use a after market one, I want to change to 4. 10 anyways.

Might be worthwhile looking at the GM "G80" Gov-Loc in your case... they operate differently and may last longer? They are the factory installed "auto-locking" differential used in the GM version of the 11. 50AAM.

I did see them on eBay all the time for almost nothing (under $150). I was considering using one in my truck because the Trac-Rite is useless in snow.