i wish this post came out a week ago...i just ordered amsoil for my nv5600 about a week ago...

 

My truck user manual simply says use GL-4 compliant lubricant, and says nothing at all about Syntorq. Interesting.

 

The NV-5600 is a completely different animal than the NV-4500HD The Amsoil will work great for you....assuming you got the GL5 MTF Fluid.

 

When the NV4500 was designed and built there was only Castrol syntorque lubricant that satisfied the requirements of the gearbox. Since then other synthetic oils have come onto the market that do meet the requirements of the nv4500. Some of these oil manufacturers specifically state that their oil is good for use in the NV4500 and they warranty it. I have yet to see anything current that says No oil other than Castrol syntorque is good for use in the NV4500. Sure my factory manual says that but its from 2001.
Dealer cost may be $18, but retail....$29, that's why I'm not using Castrol syntorque.
Even the Dodge parts guy suggested there are "other" oils out there.

 

Ok good to know. I was curious about that.

 

There should be a data tag on the transmission itself stating Castrol Syntorq LT is the required oil.

I have used alternative lubricants in the past, I am back to using the Castrol, it performs the best.

 

Wrong no other oil meets the requirements, Amsoil says it is OK to use their oil but it is not the same nor does it work as good.

 

Thanks for all the info.. looks like the castol will be my choice...now next ?, can you only get it from the dealers or can ya get it at an auto parts store? Thanks again..

Capn

 

Quad 4x4
What lubricant should I use and were can I get it?
Castrol Syntorq LTŪ 75w85w GL-4 rated, low temperature, synthetic gear lubricant is the only factory approved lubricant for NV4500 series transmissions. Some other lubricant manufacturers such as Amsoil may have products that are compatible. However, we have yet to see any other lubricant match the specifications of Syntorq LTŪ.

Castrol Syntorq LTŪ is available in quart bottles from Dodge dealers (p/n 4874459) and GM dealers (p/n 12346190). Castrol distributors offer factory sealed 16 gallon drums, plus some repackage the oil in 5 gallon pails. We sell Syntorq LTŪ in two quart jugs.