4 speed ID
Thread Starter
Instructor
Joined: Jan 2012
Posts: 215
Likes: 6
From: Mebane, NC
4 speed ID
Tried to change the trans oil tonight. No drain plug. I see where I think it should be. Round about the size, kinda has bumps on it like casting marks. It looks like it has the same paint as the rest of the trans. I find it hard to believe someone paint over a twisted off drain screw, the trans had to be out to get that consistant of a paint job.
ID numbers right side behind the big cast in Patented by GM stuff. These look like they were stamped they are vertical when the trans is installed. A large P8M17 and a smaller 185400480. Is this a vette trans?
ID numbers right side behind the big cast in Patented by GM stuff. These look like they were stamped they are vertical when the trans is installed. A large P8M17 and a smaller 185400480. Is this a vette trans?
Burning Brakes
Joined: Dec 2010
Posts: 848
Likes: 60
From: CA
P8M17 is the date the transmission was assembled. In this case it's August 17th, 1967.
The 185400480 is probably 18S400480 and is the partial VIN of the car it was installed in. In this case the car was assembled at the St Louis plant for a VERY early 1968 Corvette.
The M20 and M21 transmissions in 1968 didn't have a drain plug. Only a fill plug.
Ed
The 185400480 is probably 18S400480 and is the partial VIN of the car it was installed in. In this case the car was assembled at the St Louis plant for a VERY early 1968 Corvette.
The M20 and M21 transmissions in 1968 didn't have a drain plug. Only a fill plug.
Ed
Thread Starter
Instructor
Joined: Jan 2012
Posts: 215
Likes: 6
From: Mebane, NC
Thanks Ed. 1968, that kind of explains the wear in the shift forks. Either the PO didn't know or sold me a line of crap. I'll try to scrape some of the paint off to find out if the drain plug is broken or not. If yes maybe I can get a drill/easy out in there to get the plug out. Or maybe I'll suck it out and make the trans a next winter project.
