Is there an oil thread somewhere? I need to change the trans and diff oil and was curious as to what everyone is using.

I've been using Royal Purple 70 W 90 with good results.

Frank

I tried the Red Line MT-90, which "cured" my second-upshift *crunchiness* problem instantly.

I called all the big oil manufacturers and spoke to their tech people, and the Red Line people seemed to be the most knowledgeable- but that could have been the luck of the draw. I'm sure the big makers are all pretty close though.

This is what their website says:

"MT-90

Popular in Nissan, Toyota and Mazda manual transmissions and transaxles as well as other selected applications, this is a 75W90 GL-4 Gear Oil that’s slightly heavier than MTL. Provides excellent protection of gears and synchronizers and its balanced slipperiness provides a perfect coefficient of friction, allowing easier shifting."

FWIW.

I'm using Synchromesh in my tranny (5-speed 1981 280ZX tranny).

I haven't done anything with my diff, I probably should though.

I use Red Line in both tranny & rearend. Remember it is the tranny that takes the gl4 and the rear end gl5.

I use Red Line in both tranny & rearend. Remember it is the tranny that takes the gl4 and the rear end gl5.

Thank you!

What is everyone using as a motor oil? Brands? Weights? Synthetics vs. traditional?

O boy, you are going to see 100 opinions on this one. I have been using Quaker State 10w30 for at least 40 years with great success. However there has been some major changes in engine oil in the past few years . With all the emissions regulations in effect. The major oil companies have eliminated Zinc or its components from there oil. This has been the cause for premature failure on engines with flat tappets, also on our Nissan engines our rocker arms and cams. Valvoline RACING does have the proper Zinc. Which I have gone to. Also Delo and Rotella has the proper compounds if you use the NON EMISSION rated oil, they have the emissions rated with out Zinc There are some other brands but they are difficult to find. Gary

Edited September 1, 200816 yr by beandip

I have a friend that runs the STP oil treatment for the Zinc. He is running the rottela and the additive in his MGB with decent success. Since I've gone back to the 240Z, I am interested in finding the right oil/treatment that is most benificial to the engine. Thanks for the advice.

Don't use a full synthetic oil in the engine, semi synthetic oils are fine. In the gearbox/diff use a 75w85 semi or if driving very hard use a 75w90 semi. If it's a lsd diff use LS90

Valvoline racing 50 is a 25w60 and may be a bit of overkill unless you are driving very hard, use Valvoline Durablend 15w50 if just normal driving with a bit of fun every now and again.

In an australian magazine oil test only royal purple full synthetic and Penrite full synthetic oils beat Valvolines (semi synthetic) Durablend in engine wear out of most common oils. Red line failed as well as Motul, Castrol and Mobil etc etc. Unless your racing your wasting your money on royal purple.

In saying this I must mention I work as a branch manager for Valvoline so am somewhat biased, but I may be able to pull up the file on the engine test and post it shortly if anyone is interested.

Engine "Penrite HPR30" changing after every event.

Gearbox "Lubrication Engineers" similiar to Redline

Diff "Mobil 1 fully synthetic gear oil"

I use Mobil1 10W30 Synthetic currently. I've also used it on other engines and have found it to work. I don't usually use it on engines that have as much milage as mine does, I usually go to Mobil1 shortly after a rebuild, this time is simply because I added a turbo to the previously installed engine.