Pop-Pop

I plan to change the oil in the rear differential in the next day or so and would appreciate some guidance:

1. Should I just loosen the cover slightly or remove it?
2. Is there anything I should inspect if I remove the cover?
3. Should I change the gasket on the cover?
4. Any chance of causing leaks?

bhoeffner

Pop-Pop,

Just did mine a while back and it is way to easy.

1. I removed the cover, just see what condition things were in after the first 15K found no signs of wear or metal in the bottom of the diff.

2. Good idea to inspect the ring gear for tooth wear. That will tell if the back lash is set properly (should be on a new truck), also look for metal shavings in the bottom of the diff. sure sign of trouble.

3. I reused the gasket. It is a reuseable gasket by the way. tq bolts to 37 ft/lbs. and no leaks in 10K.

I used Mobil 1 full syn. 75-90 weight lube. This lube meets all the requirements of DXC.

Kyle Graham

Yah it is a simple procedure but I would go with a ams oil synthetic differential lube

Jeff in TD

I went with Redline, but there are many fine choices.

I would suggest using a torque wrench, as I've seen a couple of threads where people broke off bolts.

Also, the dealer contacted me and said that the level for the 11.5" rearend had been revised to 3/4 to 1 1/4" below the bottom of the hole. Newer rigs apparently have a fill line stamped into the back cover and a revised owner's manual.

1tuffdiesel

Same as bhoeffner but the service manual says 30 ft lbs on the diff cover bolts and 24 or 26 ft lbs on the plug, I can't remember which. I just did mine this past weekend and I wouldn't want to go over 30 ft lbs on the cover bolts. Make sure you have a good torque wrench as there are a lot of guys that have broken bolts using too much torque.

1tuffdiesel

That's not right info on the fill level. The manual and two TSB's note that the fill level on the 9.25 front and 11.5 rear are 1/4, + or -1/4 below the fill hole. The latest issue of TDR even speaks to this very issue and notes the same.

bhoeffner

I filled mine to 1/4 below plug. As far as amsoil it is a great product and a lot of folks use it, however it is not API certified, thus if there ever was a problem DC could give you warentee issues for not using a API fluid. After my warentee expires I will probley (spelling) switch to Amsoil.

Jeff in TD

1tuffdiesel,

Could you post a link to the TSB? My dealer gave me a thing in writing that specified the level I posted, and they pumped some oil out of my truck.

Since I tow, I wouldn't want to run the thing low, but the dealer said it could blow seals to fill it over what they said...

Pop-Pop

Thanks guys for your help. I changed the oil in the differential according to bhoeffner's instructions and it worked perfectly (except I used 30 ft-lb of torque). I used Mobil 1 75w90 full synthetic. Two things I did notice in doing the job. First, the original level was so far down that I couldn't reach it with my little finger and second, the magnetic fill plug had crud on it. I filled it up to about 1/4" below the fill plug.

Thanks much!

roadrat

tsb 03-001-04 rev a dated may 11/04 , all measurements from bottom of fill hole

10.5 rear----1in. +or- 1/4-------85oz.--------sae75w-140 synthetic

11.5rear-----1/4 +or- 1/4-------122oz.-------sae75w-140 synthetic

91/4front----1/4 +or- 1/4-------76oz.---------sae75w-90 non synthetic
This is the last tsb i can find on this subject, is there a newer one? also looks like they changed the sae grade on the synthetic to 75-140, wonder why no synthetic in the front?

rob

Jeff in TD

I googled that number and found it. Thanks Road Rat.

It appears to be titled "power locks don't unlock the rear doors". Maybe that was why I didn't find it before...

http://dodgeram.info/tsb/2004/03-001-04A.htm

I see it talks specifically about 04 trucks... Could my early 03 be different?

roadrat

jeff in TD----If you go to that web site http://dodgeram.info you can check all the tsb's for your 03 by clicking on the "technical service bulletins" at the left of the page and then click on your year at the top, all the tsb's for your truck will come up. I didn't see the same bulletin for your truck, i didn't think there was that much of a change from the 03 to the 04.

rob

1tuffdiesel

That's the correct TSB except the dodge info site seems to note the incorrect fluid type. The latest issue of TDR notes notes the same type of table shown in Roadrat's posting except to use 75W-90 Syn in the front and rear. Apparently, there is a tech tip #40 that confirms this as well. The bottom line is, the owners manual, the service manual and TSB 03-001-04 rev A note 1/4 inch +- 1/4 inch to the fill hole. I'm sticking with the owners manual on fluid capacity and type of fluid to use. If you're dealer has provided something to you in writing I would call Tech Authority to confirm if nothing else.

Karl

AaronT

Would be nice to get a correct answer on the Diff oil spec (75W-90 vs 140) and fill level.

Mine has fill level marked on cover that is 1" below what the manual and TSB says.
Ordered another owner's manual and it states the same (level +- 1/4", 75W-90 synthetic). Asked DC if this was correct and they said yes. Apparently some covers with wrong fluid level mark were installed also.
I think we need to know what the level is supposed to be relative to the axle tube to remove all the variables.

roadrat

Does a tsb not overide the owners manual? I always thought that a tsb was the most recent update to the service manual, a better way of doing things, a better product etc. Like the one that is comming out for the weather stripping If dodge doesn't want us to go by the latest tsb why bother to put them out?

rob