Review on GM Syncromesh?

[bmxryder]

Well one of my friends told me that its the best oil you could possibly put in a manual trans. So I bought 4 quarts which costs like $80. I did the oil change and noticed that it shifted a lot smoother. But then a week later my transmission blew...

I have 1 quart left and Im coming up on changing the fluid in my freshly rebuilt tranny. I would like to put that oil back in since I noticed a difference. But, Im wondering if there was a correlation with that fluid and my transmission going out. Any thoughts??

 

[racsan]

well, ive used pennzoil syncromesh fluid in my M5OD for a few years now with no problems, not sure if its the same as what you used, mine was only about 7 or 8 bucks a qt though. i would think that oil that expensive would have been a synthetic (whereas the stuff i use aint) its possible you had a issue you werent aware of and the trans would have gone no matter what oil was in it, my trans went at 80,000 miles with the correct atf in it but was low on oil with the leaking shift-rail plugs when i bought it. im now at nearly 150,000 miles. i did notice a (good) differance with the syncromesh fluid vs the atf. and i had treid many differnt atf's with no noticeable differance between them. the biggest differace ive noticed is that the shift lever doesnt get nearly as warm as it did before (i have a hurst, bare metal lever to the shift boot) and it does seem to shift smoother. i do have a issue when downshifting into 3rd & 2nd, but its done that since the trans was replaced, oil type hasnt made a differance there. i just "blip" the throttle between gears when downshifting & it goes right in. upshifting is fine so i dont think its a syncro.