Honda MTF and LE1605 for my diff with 4.77's. Works like a charm and I drive like a madman.

 

MTF: make sure, it's in the ball park of 10w30 viscosity, there's TONS of MTF fluid out there with 75w90 weight(mazda, toyota, etc)

make sure you don't use anything GL5 in your trans, or the brass syncro will be gone before you know it.

recommendation: GMSM FM, pennzoil SM(rumor to be the same as GM as 1/2 price), new OEM mtf


Diff: any GL5 75w90 will do, again there's tons of single weight fluid out there, but i would stick to 75w90 weight.

Recommendation: LE, M1, Redline


personally i use OEM MTF and m1 7590 for the street, it's a pain to pay 10 buck shipping for a ten dollar bottle of oil

 

It was my understanding that SAE reclassified the weights. Doing so made the higher numbered gear oils the best suited for our diffs (not much higher). Making the current 90 weight lighter than the old 90 weight.

Again, just what I remember reading. Maybe someone in the know can jump in here.

Best to ask this on Bob the oil guy forum.

 

I just changed my fluids and went with Honda MTF - the revised version that has been out for a little bit. Apparently it contains new additives...and so far its working very well and im impressed. Shifting has improved and going into 1st there isnt any notchyness at all. Also, today its been quite cold (-5C) and the driving experience with the car cold has not changed any noticeable bit for me. So far, the new stuff feels great. I feel, that Honda must have spent quite a bit of R&D money on improving their fluid, so that gives me piece of mind!

 

No reason to come within 100 meters of any GM tranny fluid with the new Honda MTF available.

 

Dont forget the 24mm socket that you will need in the rear for the diff drain plug

 

Good read here...

 

Thanks a lot for the information, I'm doing my diff and tranny this weekend

 

And the 23mm for the other bolt. That's much more unlikely to have around.

 

i beg to differ, new oem mtf is a very close second but gmsmfm still shift better esp when cold for me

<--almost 130k, zero grinds