Torus cover, driven torus and driving torus removed last September from a ’55 2nd series GMC Suburban with 248” six cylinder engine. Owner was rodding the running ‘Burb and was replacing the stock running gear with a 472” Caddy/TH400 combination. The transmission was put into my ’57 GMC V8 using the V8 torus parts which are different than these six cylinder torus parts. Transmission works great. Transmission is serial number CA-55-xxxx. All rivets are tight and all springs appear to be in good shape. No wear ridges on either the outside or inside of the neck of the cover. The driving torus has a crack (LATE BREAKING NEWS, IT ISN'T CRACKED -- SEE NEXT POST) on the inside flange that the rivets go through, but the crack doesn’t appear to be in an area where it would have been caused by stress. Picture of the crack attached. I have high resolution pictures of these parts if you are interested. Following info gathered from United Delco Transmission Parts Application Catalog dated February 1968. Torus cover part # 8617339 used on 53-59 GMC six cylinder models 100-340 and 54-62 Chevy truck both six and eight cylinder. Driven Torus part # 8617531 used on 54-62 GMC six cylinder models 100-340 and 54-62 Chevy truck both six and eight cylinder. Driving Torus part # 8617532 used on 53 GMC models 100-250, 54-62 GMC six cylinder models 100-340 and 54-62 Chevy truck both six and eight cylinder. I’d like to get $100 for the set of all three parts. If you buy all three I’ll throw in the Torus Check Valve (8613150) and spring (8609508). If no interest, I’d think about $50 for each piece. These things are not light. Cover is probably over 20 pounds and the other parts are around 10 pounds. Shipping of your choice will be extra, actual cost + mandatory insurance.
It isn't cracked Took the "cracked" part to a local machinist for examination. He says it isn't a crack, but flashing left over from the casting process. This opinion is supported by the fact that the "crack" does not extend down through the hole shown in the photograph. Here is another shot, closer up.
Just as a FYI: Just to confirm that the part isn't cracked, and take opinions out of the discussion, you could use Liquid Penetrant NDE on it. http://en.wikipedia.org/wiki/Dye_penetrant_inspection We do this at work (welding shop, building pressure vessels) quite often. Quick, easy and inexpensive, especially if you can find a local shop that can do it for ya.
Torus Bill, Do you still have this torus and cover for sale? I see you started this post a while back. I will but this from you if you still have it, please contact me here on the site, or at my email, gregbronn@yahoo.com Thanks, Greg
