rocktoy

I am currently reinstalling my NV4500 into my truck and was wondering if I really needed to put in the Dodge gear oil. I hate paying the dealer prices but if I have to I will. I was thinking any 75W90 oil would work but was not sure. What do you guys think.

Bob Beauchaine

The NV4500HD needs a synthetic GL4 rated oil - NOT a GL5. The difference is in the additives used to make GL5 are harmful to yellow metal in the trans. Amsoil makes a MTL that is GL4 rated - Pennzoil also makes a syn. GL4. There are others Redline recommends a 50/50 mix of their MTL and MT90 for the NV4500HD. I believe that Standard Transmission ran some tests using various oils and found that a syn GL4 held up behind the Cummins.

Bob

rocktoy

Thanks Bob. I did find the article by Standard Transmission after I posted. Need to search better.

Ace

Quad 4x4 has it cheaper. Syntorq was developed by Castrol under contract to New Venture specifically for the NV4500/Cummins application. There's a GM-equivalent, part# 12346190, in case you can find that somewhere. Probably comes from the same Castrol plant.

sooty

it is the same, theres also a dodge part number, i cant seem to find it under the syntorq castrol name, 10-20$ a quart is what youll pay, the synchros for the gear shifting are a composite material, running anything else will cause degradation, you can overfill a 5th quart with the shift handle removed