I am getting ready to service my drive train and looking in the service manual it lists using Mopar ATF +4 in the G56 trans and the transfer case. I would think that ATF is kind of light and a Syn. gear oil of some type should be used like 75w80. Any feed back on this would be appreciated.

 

Big differance in ATF (5w30wt) and 80w90. Type of metals used,bearings,synchros etc.is why certain gears oils,atf is used in what ever application. If it calls for ATF I certainly would not go and install a 80w90. Now I do wonder about the 5w30 gear oils like Amsoil MTL etc.But even on the Amsoil site they do not cross referance those two.NV5600 uses the Amsoil MTL 5w30 but the transfer case calls for ATF.Using a 80w90 you just might crater a G56 and a transfer case in a short span.

 

I got royal purple synchromax in mine. It is not atf but is it designed to replace atf in manual tansmissions and t cases.

I called and talked to them and was told it would be ideal for my truck.

I put it in about 8k ago and no problems yet. The trans is as smooth as ever but I couldnt say 100% if it is smoother or not.

I am not sayin this is what you should run but it is what I got right now and so far so good.

I got it for free is why I am runnin it.

 

just run what they tell you ...

what do you think will happen when you roll into the dealer complaining of funny noises from your new G-56 and they drain gear oil out?