Rear Axle Lube Change: What to Use

[ray1933]

Mag HyTech covers

Are these covers really worth all the money they cost.



We do not haul a lot and with the camper we are at 10K so I just wonder if they are really needed.

 

[CATCRACKER]

i used RP with modifier still working great just think the modifier is not needed not harmful but i dont know that for sure. but right now my money is where my mouth is RP in the rear.

 

[DPKetchum]

Fricton additive wont harm a non clutch pack diff. Its just there. Been put in by accident etc. and gear oils with it used in non limited slip diffs many times. No harm no foul. Kinda like oil ated for gas and diesel. Differant additives for soot etc. but still ok for gas.

 

[bighammer]

I'm at just over 15k and need to think about what to use. (following this and looking for tips)

 

[t6_man]

I contacted AAM regarding whether to use 75W-90 or 75W140. Here was my original question:



"I own an '03 Dodge 2500 HO Cummins automatic with a 3. 73 ratio limited slip differential. I understand you supply these axles for Dodge; is this correct?



If so, I have a question for you. I want to change the fluid in my differential. My owner's manual says to use a 75W - 90 synthetic lube. However, Dodge's towing guide on their web site says that if the truck has heavy duty use or tows a trailer the majority of the time, to use 75W - 140 synthetic. I have heard this information is not accurate as it was for the older Dana axle/differentials, and that I should ALWAYS use 75W - 90 synthetic in my AA axle/differential.



I tow a 30' 5th wheel the majority of the time. Which is the correct lubricant for me to use?



Thanks!



Bruce"



Here was their response:





Thanks for contacting AAM. Sorry for the delay in responding. The 75W90 synthetic lube available at your Dodge dealer is the lube that AAM and Chrysler used in testing the vehicle. It was formulated by AAM and Texaco and is used in all AAM axles. This lube is designed to provide the best solution for a wide range of climates and applications, and will perform to the towing and loads specified for the vehicle. We have not tested alternate lubes for specific applications, so choosing an alternate would rely on testing performed by the lube manufacturer.



Hope this helps.



Regards



I ended up putting Mobil 1 in; $6. 99/qt @ Autozone.

 

[Dogman]

My Dealer told me they had a TSB stating to use 75-140 for a truck that does alot of heavy towing.

 

[DPKetchum]

Want to know TSB number?

 

[Phrogger57]

Diff Oil/TSB #

Yes, Please! I am finishing the setup on my new truck for hauling and don't want/need any breakdown suprises on the road. Thanks!

 

[Casey Balvert]

Originally posted by Dogman

My Dealer told me they had a TSB stating to use 75-140 for a truck that does alot of heavy towing.

My dealer said the same thing a while back only to find out that it referred to the Dana axles in previous years. While my service guys says go ahead and use the heavier weight oil, I can find nothing official that says it is ok. I got the same answer from AAM a year ago and I thought it was rather vague.



Casey

 

[dcscott]

Bear with me as I'm a bit of a newbie. I'm overdue for a fluid change so really appreciate the help.



1) How can I determine which axles my truck has?

2) Several of you have mentioned Mag-Hytek in this 3G thread yet I can't seem to locate any Mag-Hytek for 3G. No mention of a Mag-Hytek for 3G on Geno's website or even on Mag-Hytek's site for that matter. Who carries Mag-Hytek covers for 3G?



Thanks,



Dale

 

[bighammer]

I think I will question the accuracy of the TSBs. I thought I saw a TSB for the 03 that says to use a friction modifyer for the LS axle. Someplace else I saw something that says it's not need because there is no clutch pack.

 

[DPKetchum]

The AAM axel has no clutch's in it. Its a posi unit not a limited slip per say.

 

[_Hyde]

dcscott,



Your sig says you have the HO/6sp. , you should have the 11. 5 instead of the 10. 5. I have the same combo. I got my Mag from Geno's although they didn't have it on the website. From what I've been told its in their printed catalog though. If you want people to buy your stuff, advertise it. There are a number of other people you can buy from. I bought mine from Geno's becasue they have always been good to deal with, I'm not sold on marketing alone. You will just have to call to order.



Hope this helps,



Darren

 

[Diesel Gunner]

I have a temp gauge on my rear axle and trans. When I am pulling my TT in the mountains on a hot summer day (100 deg. +) it is not unusual to see axle temps get into the 200-210 deg range. While I don't believe that this is outside of the LE-607's ability to protect the differential, I will be changing to Delo ESI 85-140 on the next axle change.



I believe that the higher viscosity will protect better at the higher temps. And, it is a general rule of thumb that one should always go with the next higher viscosity when your operating temps and adjusted viscosities fall between the lines. Also this lube uses borate technology instead of sulfate technology for the EP package and it is proving to be superior. I have seen transmissions and axles out of Class 8 vehicles that looked brand new after 750,000 miles.



As long as the lubricant you are using meets the specification for the axle or transmission you should not overly concern yourself. Now, with that said, it does not mean that lube X is not better than Lube Y. It has much to do about operational conditions (Ambient Temp, Load, etc. ) and how well mached the lubricant is for those conditions.



This is not rocket science either. Just consider what you do with your truck and where you do it. This should lead you right to the proper lubricant choice. As far a s brands, do any of us think that a person that works for Company X is ever going to tell you that their product is not as good as Company Y's? I would hope not! Unless they are short timing.

 

[Hunter1]

Had my 30,000 done today, dealer used Valvoline 75/90W full synthetic.



Looked inside the rear axle when the housing came off, that is one STURDY looking unit!



Very limited metal particles found



I have the 3. 73 LS



Hunter1