M-21 Transmission Dope
Tech Contributor
Joined: Aug 1999
Posts: 15,175
Likes: 3,990
From: Connecticut, USA
I don't use dope, but do use 90 wt gear oil 
There's been plaenty of discussion here between the new stuff on the market and the old 90 wt gear oil. I stay with the proven "old stuff" myself.
Gary
There's been plaenty of discussion here between the new stuff on the market and the old 90 wt gear oil. I stay with the proven "old stuff" myself.Gary
Race Director
Joined: Feb 1999
Posts: 19,659
Likes: 34
From: Lenoir City Tennessee
Ci 6, 8 & 10 Veteran
St. Jude Donor '05-'06-'07-'08-'09-'10-'11-'12-'13-'14-'15
I put the Mobil sythetic that they sell at Autozone in mine. Seemed to make it shift smoother IMO. Could also be that the old oil was needing changing in a bad way though.
Melting Slicks
Joined: May 1999
Posts: 2,897
Likes: 0
From: Moon Township PA
Originally Posted by Eddie 70
I put the Mobil sythetic that they sell at Autozone in mine. Seemed to make it shift smoother IMO. Could also be that the old oil was needing changing in a bad way though.
Mobil 1 80W-90 in both the differential and the trans. Love the stuff.
Gary
