had differential service today - help!!!!

[sag2]

I posted about a month ago about adding friction modifier. The dealer added it to my 03 right before I got the 04. It jumped like crazy on turns. I drove it for a while before I got the new one. I guess in a way, it felt like the LSD was working harder than before, just a little jumpy.

 

[Dean Upson]

Originally posted by FParlee

Gentlemen,



My first even Ram/CTD should be here next week. So I know not what I speak of... ... .....



But, what is the diff. change interval on the 3rd Gen trucks? Everyone is talking about changing their diff oil on 03' trucks. Are these super hi mileage trucks? Shouldn't it last for a few years?



HELP!!??

The gear oil change interval on the diffs is 15K per the maintenance schedule, this seem excessive to me, but that is the way it is.



Dean

 

[Spooled-up]

They recommend that you change every 15000 as Dean said, but that is the severe service schedule. Since stop and go driving and sustained high speed driving in hot weather are part of what defines the severe service schedule, I can't imagine a truck that would have to use the less frequent change intervals. I believe schedule A is normal service and schedule B is severe service.

 

[Dean Upson]

I doubt that there are many of our trucks that would fall into the "A" schedule.



Dean

 

[FParlee]

So the diff change interval and the engine oil interval are the same?????!!!!!!!!!!:--) :--)

 

[Dean Upson]

Originally posted by FParlee

So the diff change interval and the engine oil interval are the same?????!!!!!!!!!!:--) :--)

Your engine oil change interval will likely be the "B" schedule as well and that would be a max of 7500 miles.

Dean

 

[FParlee]

Dean,



Ya got me!

 

[ToolManTimTaylor]

You mean you are supposed to change diff oil !? :-laf :-laf I change it when I get to it. Still on oem in the 01 (52,000) Every one of my chevy's got a diff oil change at or around 100K No leaks , groans , nada.



Now my motor get is every 3,000 weather it needs it or not , My trans every 20,000 and same with T case.

 

[Badunit]

I would doubt that the cover bolts bottom out. The tolerances in bolt hole depth and bolt length would be hard to manage and the cover probably wouldn't be evenly held down with bottomed out bolts.



What is the problem with using 75W-140 vs 75W-90? I would think the 75W-140 would be better, though might not be necessary. I can't see that it would do any damage.

 

[mbaston]

A couple things:



1. Those gaskets cost me 24 bucks apiece. I didn't know they were re-usable until after I just read this post.



2. Is everybody taking the cover off to drain? Using a suction device to pull the oil out is insufficient?

 

[bkaiser]

I changed the rear a few weeks ago, will change the front when it warms up a bit. The rear took a little over 4 quarts to fill to weeping.



The bolts don't bottom - the gasket has compression stops built into it. These are basically washers cast into the polymer that will prevent over compression of the gasket. It won't stop you from over torquing the bolts and snapping them off, but you shouldn't be able to squeeze the gasket out from under the cover.



The gasket is a nicely engineered piece, I can see why it costs $24. It's just too bad we all get to look at these gaskets so soon - 15,000 seems way too short an interval for this change.

 

[MABurns]

I am still perplexed why it doesn't have the drain plug on the bottom off the housing like the AAM on the GMs have.



15,000 miles ? Can't figure that on out either. GM is using the same axle made by the same company and that is not their interval... .....

 

[bulabula]

Originally posted by MABurns

I am still perplexed why it doesn't have the drain plug on the bottom off the housing like the AAM on the GMs have.

Has anyone priced out the cost of a GM AAM housing cover with drain plug?



Since we're supposed to be under the diffs every 15k, I like the idea of a drain plug - and hopefully not having to spend the big $$$ on an aftermarket alum cover.



Hmmm, we get the short interval drain axles and NO drain plug, and GM has long drain interval periods and gets the drain plug? You're right, something doesn't make sense here.

 

[Dean Upson]

Originally posted by bulabula



Hmmm, we get the short interval drain axles and NO drain plug, and GM has long drain interval periods and gets the drain plug? You're right, something doesn't make sense here.

If you price the Mopar GL5 75w90 you will see that the inflated price makes "cents" to D/C.



Dean

 

[dspickes]

I came across something tonight that was interesting on this subject. Seems the Dodge towing guide at http://www.dodge.com/towing/D/basics/terms_conditions.html states:

"Tow vehicles equipped with the Trailer Tow Group option should use synthetic axle lubricant, which is standard on all 2003 Ram Pickup Trucks.



For all trailer towing or heavy duty applications replace the factory fill rear axle lubricant with an SAE 75W-140 synthetic gear lubricant. Mopar Synthetic Gear Lubricant (MS-8985) is of this type. Perform the maintenance listed in Section 8 of this manual. When towing a trailer, never exceed the Gross Axle Weight Rating (GAWR). "



Has anyone been replacing the 75w90 with the recommended 75W140 at the first 15k miles or otherwise? (I don't find anything in the service manual about this replacement or even being an optional grade of lube. )



I'm confused.



Doug

 

[Forrest Nearing]

I've never used anything but RTV on differential covers...

 

[Casey Balvert]

Originally posted by dspickes

I came across something tonight that was interesting on this subject. Seems the Dodge towing guide at http://www.dodge.com/towing/D/basics/terms_conditions.html states:

"Tow vehicles equipped with the Trailer Tow Group option should use synthetic axle lubricant, which is standard on all 2003 Ram Pickup Trucks.



For all trailer towing or heavy duty applications replace the factory fill rear axle lubricant with an SAE 75W-140 synthetic gear lubricant. Mopar Synthetic Gear Lubricant (MS-8985) is of this type. Perform the maintenance listed in Section 8 of this manual. When towing a trailer, never exceed the Gross Axle Weight Rating (GAWR). "



Has anyone been replacing the 75w90 with the recommended 75W140 at the first 15k miles or otherwise? (I don't find anything in the service manual about this replacement or even being an optional grade of lube. )



I'm confused.



Doug

I think that might be some left over wording from a previous model year. Who knows, so much of what DC prints is contradictory. Nothing else that I have read recommends the heavier oil. Having said that, I wrote AAM when I first bought my truck and was searching for some answers on this question. They wrote back saying their engineers feel "there are certain advantages to using the heavier oil" but fell short of actually recommending it as DC did not state to use the heavier stuff. My service manager advised me if was his truck and towed the weight that I was, he would go to the heavier oil. With half these axles whining anyway, it don't see that it can hurt. I ordered a case of Redline 75W140NS WITHOUT the friction modifier and will be going to that before the camping season starts. My truck is winter-stored so cold temperatures are not an issue with the heavier oil. I too would like to hear from anyong else using the heavier weight oil.



Casey

 

[Dean Upson]

My understanding is that the requirement for the heavier gear oil does not apply to American Axle diffs. There was a great deal of confusion about that when the switch was made from Dana to AA for the '03 trucks.

As for what is said on the various manufacturers website; I take them with a grain of salt unless I know that they have recently been updated, many of the sites have very old and incomplete information. I am more inclined to go with what it says in the owners or service manuals.



Dean

 

[Tejasdge]

I changed front and rear yesterday with 75W90 Royal Purple. All the cover bolts had red loctite on them. What a PITA. Did the rear first and didn't figure I needed to clean the bolts. Big mistake. Ended up conducting yield tests on one bolt. (Only about 25 ftlbs to stretch that one. ) I hate the feeling when it doesn't ever get to the click on the torque wrench, but fortunately I stopped before it broke. Wire brushed the front bolts. The holes should have been chased with a tap but I was in a hurry to watch the pathetic first half (actually 28 minutes)of the game. Didn't use loctite, don't want to go through this again every 15K. Also air tools are very handy to have for this job.

 

[Ron Civita]

Mbaston asked about using a suction device to remove the gear oil. Is this a feasible alternative? Thanks.