Does anyone know if my 2005 Dodge/ Diesel front and rear diff come with
synthetic oil ? and if so would it be identified some where?

 

Yes, all AA&M axles come fron the factory with synthetic 75W-90 in them. I have no idea what brand gear oil it is, but it is syn. Welcome to DTR, by the way!

 

I have seen alot of people in here recommend Mobil 1 Synthetic for the diffs but I was in Oreilley's today and all they had was Quaker State full syn. Anybody have any dealings with this or should I just stick with Mobil 1?

 

I put Royal Purple full synthetic in mine, no probs

 

You can also order Amsoil, Redline, etc. off the net and get along very well with it. I am currently running Amsoil 75w-140 Severe Gear since pretty much every mile my truck drives is towing, and so far so good. I have an Amsoil Commercian acct. however, which makes it about 2/3 the price off of the shelf Mobil 1, which is also a fine oil.

 

I run Amsoil Severe Gear 75W90. It's too cold up here in AK to run the 75-140.

 

Do the limited slip equipped axles require a friction modifier?

 

No, the AAM LS axles do not need friction modifier. I believe the older Dana axles on 2nd gens did, but DC says not to add it to the 3rd gens.

 

You can run any synthetic GL-5 rated 75W90 or 75W140 gear oil and be fine. If you want to run Mobil 1, you can get it at Autozone, if they have one near by you. I use Mobil 1 75w90 and have had no probs.

 

Thank you.

 

Thanks TexasCTD. I forgot about them. I should start calling them Oil Zone because of a great selection compared to others!

 

Actually, I usually refer to them as "GhettoZone" . But at least they have what I want even if I do have to go to 2 or 3 different ghettos to get it all.

You and Pauly are both very welcome. Im just glad to be able to chime in and help out sometime. Changing out the diffs is just as easy or easier than changing the oil, although I had never done it until I got my current truck.