1957 4 speed transmission questions

[Gary C.]

Re: 1957 4 speed transmission questions

Mike,

Wasn't there a difference in the plate between the main case and the tailshaft for 1957 4 speeds?

Gary
....

[Mike M.]

Re: 1957 4 speed transmission questions

not that i'm aware of. all mine had an aluminum intermediate plate. maybe the early cast iron tails had cast iron intermediate plate but that's just a guess. never seen or examined one of the prototypes with cast iron tail housing. not even sure they ever existed. who knows, not me. mike

[Gary C.]

Re: 1957 4 speed transmission questions

Mike,

Think I have still one somewhere. IIRC the holes were smaller in the '57 aluminum adapter plate?

Also, wasn't the reverse slider different with fingers on it?

Gary
....

[Dan P.]

Re: 1957 4 speed transmission questions

the mid plate was aluminum.Is you main case a T10 or T10 1b. Is the raised casting around the fill plug oblong or round .The T10 1B was oblong because they lowered the fill plug to lower the level of gear oil . It was bubbling out when hot.The case you show in the picture has the rib that was added on the T10 1B at the reverse idler gear. . MANY of the main cases were replaced because of the reverse idler would fail and break the case . They changed the design in 1960 .SO it is very possible you have a replacement main case .SO no assembly stamp.What is the cast date on the main case.Shifter and rear trans mount bolts all were 3/8.

[Brice T.]

Re: 1957 4 speed transmission questions

photo of RH side of case........

[James G.]

Re: 1957 4 speed transmission questions

Thanks all. I always enjoy more knowledge. I also have had a few of these cars

[Dan P.]

Re: 1957 4 speed transmission questions

That is a T10 1B August of 59 60 or 61 .Notice the oblong casting around the fill plug.

[Brice T.]

Re: 1957 4 speed transmission questions

So it most likely started out as a factory 4 speed car and has had the transmission main case replaced. Hopefully the tail shaft housing is the original one.

[Mike M.]

Re: 1957 4 speed transmission questions

no way to be absolutely sure that your 57 started life with a 4 speed, but u have the most difficult piece of a 57 t-10, a real 57 tail housing.. i'd look for a 57 side cover without the gussets and a t-10 cast case. then nobody can dispute the idea that the car has what appears to be an original 57 t-10. hope to see it on the NCRS judging fields of the future. mike

[Patrick S.]

Re: 1957 4 speed transmission questions

T10 pictures from my 57. Believe it is original.

[Joseph T.]

T10 Blueprint

T10 Blueprint

[Joseph T.]

Re: 1957 4 speed transmission questions

With no assembly stamp on the left rear of the main case, the trans may have been assembled by "Bubba's 4 Speeds", with the intent to be able to show the cast iron main case and the aluminum tailshaft. It might also call for a picture of both sides of the tailshaft extension just to make sure of who made the date castings. There should be two "half-moon" indentations in the end of the extension that facilitate access to the rear seal. One of the best indications of a "real" '57 extension is to remove one of the bolts into the extension at the rear mount - if it is a 3/8" bolt, it's 90/10 that it's real. The General later made those holes for a 7/16" bolt.

Loren my friend, check online GMPartswiki.com which contains service books. You may find a reference to the bolt discussed above.

Joe

[Joseph T.]

Re: 1957 4 speed transmission questions


T10 from 57 #4353