I also filled mine when it was cold
M21 fluid level?
Thread Starter
Instructor
Joined: Jul 2004
Posts: 210
Likes: 0
From: Lakewood CO
M21 fluid level?
The repair manuals I've seen all list something different so I'm wondering what other people use as a reference for their fluid level. I've searched the archives and didn't find much.
I've seen fluid amounts vary from 2 pints to 3 pints. I've read that the level must be even with the fill plug cold and I've read manuals that say it should be that level when at operating temp. I've also read that it should be 1/2 inch below the fill plug when cold.
Mine is currently 1/2 inch below the fill plug when cold. If I put anymore in it it will just leak out the front hole.
Help me determine if I have the right fluid level.
Thanks,
Dave
I've seen fluid amounts vary from 2 pints to 3 pints. I've read that the level must be even with the fill plug cold and I've read manuals that say it should be that level when at operating temp. I've also read that it should be 1/2 inch below the fill plug when cold.
Mine is currently 1/2 inch below the fill plug when cold. If I put anymore in it it will just leak out the front hole.
Help me determine if I have the right fluid level.
Thanks,
Dave
Thread Starter
Instructor
Joined: Jul 2004
Posts: 210
Likes: 0
From: Lakewood CO
When you fill it to the hole, is your tranny cold or at operating temp?
Mine is 1/2 inch below the hole when cold. I haven't checked it when it is at operating temp. Does it even make a difference?
Dave
Mine is 1/2 inch below the hole when cold. I haven't checked it when it is at operating temp. Does it even make a difference?
Dave
Drifting
Joined: Oct 2003
Posts: 1,486
Likes: 10
From: Big Pine Key FL
filled it to the hole in my M-21...
Synthetic makes a HUGE improvement in shift quality... Just did it last Saturday along with the differential.
Call it it's last supper before I order the ROD 6 speed....
Synthetic makes a HUGE improvement in shift quality... Just did it last Saturday along with the differential.
Call it it's last supper before I order the ROD 6 speed....
Le Mans Master
Joined: Mar 2004
Posts: 7,502
Likes: 1,510
From: Little Rock AR
You fill it carefully up to the bottom of the fill hole threads when the tranny is at operating temperature and the vehicle is on level ground. It will then leak out on to the level ground untill the height of the fluid equalizes with the level of the rear seal within a few days. 
-Mark.
-Mark.
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