If I were to use 5w40 synthetic in my Getrag, could this send it to an early grave? I got an unreal deal on Rotella synthetic from the clerance rack at a Maryland WalMart. THANX FOR YOUR HELP.

 

Not sure if the Rotella syn meets the tranny requirements, but, most of the guys are running the Mobil 1 5w30 synthetic + 1 quart overfill for added life.

 

I think it might be too thick and make for stiff shifting. Dodge called for 5w-30, but I'm real happy with the Redline MTL I put in mine.

 

The reason the Germans spec'ed 5W30 was due mainly to the close tolerences in the Getrag. Synthetic was recomended to handle the heat. When I had my Getrag rebuilt I used 5W30 as recomended. The tranny was still too noisey so I switched to 5W50 full synthetic. The tranny worked quite well - about the same as with the 5W30 syn. but was still too loud. I finally got tired of the noise and went to the NV4500HD - problem solved ;D ;D. Temp's in the Getrag were about 175 on a 100 degree day - non towing. My NV runs about 25 degrees cooler under the same conditions and you can hear yourself think in the cab. Although I missed the noise : : I decided I would rather listen to a 4 inch exhaust ;D ;D.<br><br>BTW I still have that Getrag boat anchor with about 1500 miles on it sitting in my garage.<br><br>Bob