m22 trans 71 vette

[Barry Chappell]

Re: m22 trans 71 vette

Trivia - I have a June built '70 with the two plugs.(M21)

[Terry M.]

Re: m22 trans 71 vette

More trivia -- My January built 1970 (POA20B Muncie built January 20, 1970) has a drain plug

[Joe L.]

Re: m22 trans 71 vette

Michael-----

As of June, 1970, the 3925661 was the main case being sold in SERVICE for all 66+ Muncie applications. This main case has the drain plug, SERVICE or PRODUCTION.

The 68-69 main case for all applications except M-22, was GM PART #3925658. This is the main case with casting number 3925660. It does not have a drain plug, although the boss is present for one as is the case for all other Muncie main cases.

In June, 1970, the GM PART #3925658 was discontinued from SERVICE and was replaced by the GM #3925659. This is the case with the 3925661 casting number and with the drain plug.

[Joe L.]

Re: m22 trans 71 vette

Tom------

In the future, after I get my "ZL-1" and M-22 installed in my 1969, I am going to be rebuilding the original M-20 for eventual re-installation in my car with the original engine, already rebuilt and stored (which may not occur until after my demise depending upon how much I like the "ZL-1"). Incidentally, the original transmission has never been rebuilt, has 200,000 miles on it, and still works absolutely perfectly, but it's really time to go through it, anyway.

That "do-nut" magnet in the bottom of the case is one of my biggest "quandries". I really don't want to drill and tap the case for a drain (with a magnetic plug). There's really no sense in losing this element of original configuration, especially since it will likely never be necessary to drain the transmission fluid after the rebuild and re-installation. If it ever is (and I'm still around to do it), I can alsways use a suction gun. However, that "do-nut" magnet has always worried me. As you know, it's attached to the case with an adhesive. If that adhesive ever "let go" that magnet would immediately attach itself to one of the gears and VERY shortly thereafter be "crunched to bits", possibly taking gear(s) with it.

Actually, I do have a few of the GM magnet kits with included adhesive. However, my inclination is going to be to remove the magnet and not replace it. It's just always worried me to have it in there.

[Robert C.]

Re: Magnet

Joe, Just put one of those big do-nut magnets on the outside/ bottom of the oil filter. That will get the job done.

[Patrick H.]

Re: Magnet

Bob,

I'll play stupid here -
How will one of those on the bottom of the oil filter help the transmission?

Hope you enjoyed the Retreat this past weekend.

Patrick

[Terry F.]

Re: m22 trans 71 vette

I would personally not attempt to glue a magnet into a case that has been used. No mater how much you clean the inside of the case, the aluminum will absorb some of the transmission lube and possibly effect adheision. I would be worried about it coming loose then. A brand new case might be different. Then it might hold well.

I tried to chip on off once, it was suprisingly stuck on there. Just my thoughts. Also, that magnet seemed sort of brittle and easy to crunch up. It might just desintagrate. I to would not want to find out. I have never seen one missing from inside the case though. Later, Terry

[Terry F.]

Re: m22 trans 71 vette

Joe, do you plan on using a double disc clutch on your ZL1? Will you be using an M22 transmission? Just wondering, Terry

[Joe L.]

Re: m22 trans 71 vette

Terry-----

No, I won't be using a dual disc clutch; no original ZL-1 or L-88 ever used one, either.

I will be using an M-22 transmission, though. I have a "brand new" example. I put it together from 100% NOS parts that I mostly purchased 20+ years ago.