What oil in Differentials?

[BZieg]

I was wondering how much, and what oil you guys run in your differentials? It's a 2004. 5 2500 4x4 with AAM axles, not sure of the size though(axles). Also it's time to get the transmission serviced, does anyone know a reputable shop here in So. Cal near San Diego or Riverside? Thanks. -Bobby

 

[BZieg]

p. s. while doing this should I do the transfer case as well? And if so what oil and how much? Thanks again you guys are always super helpful. -Bobby

 

[rbattelle]

In my axles I've been running Valvoline Synpower 75w-90. But on the next change I'm going to try Kendall Elite 75w-90 (I've been told it's the same stuff).

Be sure to get a GL-5 full synthetic, and no matter what the shop tells you, limited-slip additive is not required.

Transfer case gets ATF-4.

Front axle (9. 25" ring gear): ~3 qt
Rear axle (11. 5" ring gear): ~4 qt
Transfer case: ~3 qt

Ryan

 

[MMeier]

Been running Lubrication Engineers LE 607 in my diffs for quite some time now. With the Mag Hytec covers I get just about 8 qts in the rear and just under 4 in the front. Been running Amsoil ATF in the transfer case also.

 

[RVTRKN]

I was wondering how much, and what oil you guys run in your differentials? It's a 2004. 5 2500 4x4 with AAM axles, not sure of the size though(axles). Also it's time to get the transmission serviced, does anyone know a reputable shop here in So. Cal near San Diego or Riverside? Thanks. -Bobby

I don't know what oil you have ran before, but Frahm Dodge in Norco (Riverside) is the only shop that has touched my vehicles. The service writer is Patrick and he is there best writer. I only run oil that they have in their shop and don't know what the oil is, but I have 50K on my 04. 5 and I have never had any issues with there oil.

 

[CDonaldson]

I'm a DIY kind of person, changed ALL my fluids - transmission, xfer case, diffs at 5K to new Mopar fluids to get rid of the break-in stuff, then over to Amsoil fluids at 15K.



I live in a HOT climate, HOT roads about 9 mos of the year, and I tow a LOT, so I run 75w140 in my diffs. Auto transmission fluid in the transmission and xfer case.



I am now at 30K, sent in oil samples to see where my diffs, transmission, and xfer case were on possibly the need to change out the fluid - my reports came back telling me that my oil in everything was just as good as when I put it in new!!! When I changed out the Mopar fluids to the Amsoil fluids, I sent in samples just to see what 10 K had done to them, believe me when I say that the diff fluid had little to no visconsity left according to the reports. I think that baby oil would have had more going for it. To think that many people actually wait and change their stuff out at the recommended 15 K on a new truck, no wonder Dodge has all the axle problems they did in the 2006 models, their break-in stuff smells like old stinky fish, after 10K on their fluids more stinky fish and a horrible sample report too.



CD

 

[Okie-Go]

I also have the Amsoil in mine. I tow quite often and it stays fairly warm in here in Texas where I live. I found in odd that the transmission fluid for the G56 was thinner than I thought it would be.

 

[steved]

I run Royal Purple 85w140 in the rear, Royal Purple 75w90 in the front, and Royal Purple SynchroMax in the tcase.

The rear is supposed to take 4 quarts, the front is around 3 quarts, and the tcase takes around 3 quarts.

 

[MA2LA]

I am getting ready to do all my fluids again and adding a good rear diff cover. I royal purple 75w90 ok in the rear if you not pulling 14k all the time? the main reason I'm asking is I plan on buying a 5gal bucket of gear lube and if I can use just the 75w9 instead of the 85w140 then I'm good to go in the front and in my Jeep axles. Also would there be any difference in fuel mileage?

 

[steved]

75w90 is the spec'd weight for our trucks... they recommend 75w140 if you tow. I run 85w140 mainly because I got a smoking deal on it ($29 for a 5-gallon pail). There are lots of guys towing with nothing more than 75w90 in the differentials.



I actually saw an increase in mileage running 85w140 over the previous fill of 75w90 Mobile 1... so depending on what you have in there now, you might see an increase.

 

[JPul]

I just installed a Mag-Hytek cover on the rear diff and put in 7 quarts of Amsoil 75W110. This amount of fluid is distinctly higher than the level would be just below the plug on the standard cover but the 7 quarts did not put it up to the top of the indicated region on the dipstick. I think 7 is enough. I tow a 9K fifth, so it isn't heavy towing. I felt the 75W110 was a nice tweener between the 90 and 140.



Regards, john

 

[Ducman82]

im running royal purple 75w90 front and read with Mag-Hytec covers as well. love it! i also used RP max Atf in t-case

 

[SOLER]

Anyone have the torque specs for the 14 bolts (rear) and the fill hole bolt? I've got a dually. Thanks

 

[LRutigliano]

Anyone have the torque specs for the 14 bolts (rear) and the fill hole bolt? I've got a dually. Thanks

The Dodge Service Manual states 30 ft-lbs for the diff cover bolts. These are M8 bolts holding a stamped steel cover. I was afraid to go to 30 ft-lbs (didn't want to snap the bolts... ). I went to 20 ft-lbs with some loctite 242 (blue) on the threads.



The DSM states 24 ft-lbs for the fill hole plug. Again, 20 ft-lbs for me...



Hope this helps,

Louis

 

[steved]

I remember there being discussion that the ft-lbs should have been inch-pounds...



With that said, I usually just snug them up by hand.

 

[rbattelle]

With that said, I usually just snug them up by hand.

Me too. There have been stories of people snapping the heads off at the factory torque setting.



Of course, your average dealer differential changer probably just runs 'em down good-'n-tight with the impact gun. :-laf



Ryan

 

[firemansdiesel]

Yeah, I just go hand tight also w/ the bolts and fill plug.

 

[WUnderwood]

yep, they are very easy to snap off, be careful

 

[amsoilman]

Read this!



AMSOIL - A Study of Automotive Gear Lubes

 

[DPellegrin]

... and the winner is--you guessed it, AMSOIL. I sure didn't see that one coming!!! Pull-ease!!