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One of the guys in my local car Club has a 40 Olds with an Olds 455 V8 and a gm 375 "slim Jim" transmission. He Said The transmission was not shifting properly, and when he opened up the trans and valve body he found this Part was broken. It seems to be spring metal, and was previosly bent.
Can somebody help us to identify the name of this part? Any leads where to find a replacement would also be welcome.
Thanks and happy New Year!
Mike

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These Trannys are well known in the Pontiac world, try here:
http://forums.performanceyears.com/forums/index.php

The "Slim Jim" was also used on all full-size Olds from '61-64 but only on Pontiac Catalina/Ventura. The Pontiac Star Chief and Bonneville used the 4 speed "Jetaway."

GM also made a 375 which was another version of the turbo 400 a much better transmission more likely to be behind a 455 engine . The slimjim was was not one of better transmissions from GM or maybe one of the worst.

Thanks for the links. Maik (german writing of Mike) my freind with the Olds found out what it is. "Front clutch bypass valve" and he had a new one made locally.
I think we have found a tranny that has a shorter production run, and a worse reputation than the ultramatic!

"Slim Jims" were notorious, a truly terrible transmission.