mattn124

Looks like I've got a leaking pinion seal on my rear axle.

Can anybody help me identify which axle I have? I have a 1999 factory service manual, but the numbers dont match my truck.

My glove box tag has the code DRL for my rear axle and says it's a Dana 80/Hyp

the numbers on the diff cover are as follows:
DANA
42434
288 8
REV AB
05 02 94

So I have a Dana 80, but my service manual identifies axles by a different number system. It offers info on:
216 and 248 FBI axles
248 and 267 RBI axles
286 RBI axle
9 1/4 Rear Axle

So which one is mine? There is no tag anywhere on the axle identifying it. I am guess I should look at the section on the 286 RBI axle but not sure

Also, can someone tell me if I have the standard diff or a trac-loK one? Sometimes I hear this referred to as limited slip or open.

I know one of these requires a friction modifier added to the gear oil and I am going to do a fluid change at this time as well so that's something else I need to know.

I've been topping it off with Castrol Syntec 75-90, but haven't decided if that's the fluid I will put back in.

Lastly, what about a diff cover gasket? Should I just use rtv, if so what are some types that people have had good results with?

Truck is a 1999 Cummins 2500 4x4, quad cab, 5 speed short bed.

Thanks for any info
Matt

1-2-3

80's are for duallies, 70's are for singles, so you will have a Dana 70. *)'s are shorter. And yes, just use an rtv silicone in place of a cover gasket. Not too thick though. Also wipe the surface of both the cover and the housing with a brake cleaner, coleman fluid, etc. Anything that will eliminate any oil film. The a small amount of liquid tephlon on the plug threads.

If you have a limited slip diffrential, be sure to add some friction modifier. I think 4 ounces. I put a bit too much inmine and it wasn't as tight as I would have liked it to be. There should be a tag on it that has LS stamped in it. Or you can rais both wheels and with the truck in park or in gear (just keep the drive shaft from turning) rotate one wheel. if the other rotates the same way, you have a LS. If it rotates the oposite way you DO NOT have a LS.

CTD NUT

His truck is a 5 spd - it is a D80 which is the 286 RBI. D70's were only in 2500 Automatics.

Just for reference:

216 FBI = D44 Front
248 FBI = D60 Front
248 RBI = D60 Rear
267 RBI = D70 Rear
286 RBI = D80 Rear
9 1/4 = Chrysler Corporate 9 1/4" rear

The 216 FBI, 248 RBI and 9 1/4" do not apply to Cummins powered Dodges.

mattn124

ok, thanks CTD nut,,,

That's exactly the info I was looking for

Now, is there any way to tell other than spinning the tire if I have the limited slip diff?


Thanks!!

Matt

CTD NUT

When you have the diff cover off look to see if you have clutch packs behind the side gears in the diff. Also, if it is a LSD, look at the spider gear cross pin where is comes through the carrier case. If the cross section profile of the pin is not round but is cam shaped, you have a Powr-Lok which is a much better LSD than the crappy Trak-Lok.

1tondodge

there is a six digit number stamped in your passenger side axle tube. ex. 603211-1, that will tell you what axle, gear ratio, carrier, etc that you have. Post it up and we can look it up.

JAX

It should also be printed on the sticker inside your glove box if you have the limited slip.

mattn124

Well, inside the glove box the code no. for the rear axle is DRL, and it also says Dana 80 Hyb on the glove box sticker.

I just crawled under the truck, found some numbers on the bottom of the passenger side of the axle housing. Hard to read even after I cleaned it up, but here goes:

TL3, then maybe a 4. then a space where I cant tell if there's supposed to be a letter there or not, then 08796601 XN

so thats TL 3(4)??08796601 XN with the ?'s being possible numbers I cant make out

That number doesn't match anything I found here: http://dodgeram.org/tech/specs/axle/286RBI_specs.html

Almost out of daylight and unfortunately I have to go to a wake tonight so I won't be able to crawl back under the truck to check those numbers or look for others tonight, but I can tomorrow

Thanks for all the help guys!

CTD NUT

If you are taking the diff cover off anyway, all of your questions will be answered without having to go through the trouble of deciphering any codes....and there is no manufacturing code that will tell which LSD you have - only that you have one.

mattn124

Thats true, I will be taking it off so I will end up knowing exactly what I have.

I would like to know at least if I have a LSD or not before I take it apart, just so I can have everything on hand, hard to drive to the parts store with the diff apart,, haha!

I guess I could always buy the friction modifier additive,, and if I end up not needing it I could just take it back to the store..

Thanks again for the help!

Matt

riddle789

if you want to go with a synthetic gear lube, get royal purple then you are covered whether it is limited slip or not, it has the friction modifier in it already....