Engine/Transmission (1998.5 - 2002) castrol syntec 75w-90 and castrol syntorq 75w-90 the same?

[MxerChris]

are they the same or have I put the wrong thing in my transmission? I put in the syntec it has a GL-5 rating.

 

[redram]

No - Castrol Syntorq is a API GL-4 rated transmission oil.



Castrol Syntec, if it is only rated as API GL-5, should only be used in differentials or manual trannys calling for an API GL-5.



The NV4500 calls out a API GL-4 rated oil and in this case, the GL-5 oil is "NOT" better for this type of application.



Royal Purple makes a dual rated 75W90 product called MaxGear 75W90 that I have been using for over 110,000 miles in my NV4500 with excellent results.



Available at some Napa's or find at their website, www.royalpurple.com.