Clutch part ID for Joe Lucia

[Larry C.]

Hey, Joe,

I have an NOS Corvette 11" clutch disc in a GM blue/white box marked part #3758678. According to my Feb 1971 Corvette Parts book used over-the-counter at Chevy dealers, it lists this part # for 1955 Corvette. Seems strange that 55 clutch disc would be 11" while later years were 10" or 10-3/8" discs depending on year/engine.

Do you know of any other application of this part #?

Thanks,

Larry Chilton

[Joe L.]

Re: Clutch part ID for Joe Lucia

Hey, Joe,

I have an NOS Corvette 11" clutch disc in a GM blue/white box marked part #3758678. According to my Feb 1971 Corvette Parts book used over-the-counter at Chevy dealers, it lists this part # for 1955 Corvette. Seems strange that 55 clutch disc would be 11" while later years were 10" or 10-3/8" discs depending on year/engine.

Do you know of any other application of this part #?

Thanks,

Larry Chilton

Larry-----


Yes, 1955 Corvette did use an 11" clutch disc. An 11" clutch did not appear again in a Corvette until 1966 big blocks.

The GM #3758678 did have other applications. However, they were all truck applications including:

---54-55 series 6 with 6 cylinder engine

---55-58 series 3 (forward control chassis)

---55-56 series 3 with V-8

---57-58 series 3 with HD clutch (except forward control chassis)

---59 series 3 (except forward control chassis)

---60-62 with 4 wheel drive

---60-62 series 10-30 with HD clutch and 6 cylinder

---60-62 series 10-30 with 283

I doubt those non-Corvette applications are going to have too many survivors these days.

[David L.]

Re: Clutch part ID for Joe Lucia

Larry,

I'm not Joe but my 1963 Chevrolet Parts Catalog (Oct. 1962) lists GM # 3758678 in Gr. 0.886, described as "woven (11") steel backed facing (hub painted white)", and is for the following models:

54-55 COMM., UTIL. w/H.D. Clutch (1st Series)
55-59 Ser. 3 w/H.D. Clutch
60-62 4 WD
60-63 Ser. 10 thru 30 (283)

GM # 3758678 is not listed in my 1957 Chevrolet Parts Catalog (Mar. 1957).
My 1957 catalog lists GM # 3729782 (10") for the 1955 Corvette (8 cyl.) and 56 PASS. w/4BC (exc. O/D, hvy. duty).

Dave

[Larry C.]

Re: Clutch part ID for Joe Lucia

Many thanks to both Joe and Dave for extremely thorough responses. Couldn't ask for any more than that. Now to figure out what to do with it since it fits nothing I own.

Larry

[David L.]

Re: Clutch part ID for Joe Lucia

Larry,

GM # 3758678 is also listed in my 1960 Chev. Truck Parts Catalog (Nov. 1959) for various models with 6 cyl. and 283 engines.

My 1964 Chevrolet Parts Catalog (Oct. 1963) lists GM # 3758678 for the 55 Corvette and various 55-62 Chev. trucks. My 1964 parts catalog also lists GM # 3779757 for the 55 Corvette (8 cyl.).

Dave

[Joe L.]

Re: Clutch part ID for Joe Lucia

Many thanks to both Joe and Dave for extremely thorough responses. Couldn't ask for any more than that. Now to figure out what to do with it since it fits nothing I own.

Larry

Larry-----


There MAY be an error in several of the GM P&A Catalogs. The catalog I first check showed the 3758678 as being applicable to the 1955 Corvette application as well as the others I mentioned above. However, as I did some more research I found the following:

The original clutch disc for 1955 Corvette V-8 was shown as GM #3836708. It was discontinued in August, 1957 and replaced by GM #3741091.

A 1957 edition of the P&A catalog shows the 1955 Corvette clutch disc as GM #3729782. This was superceded as follows:

3729782---->8/57----->3737946---->11/57------->3741091----->4/59------->3751952------>12/60----->3777086----->3/61------->3779757------>8/66------>3889346----->discontinued without supercession 7/85.

ALL of the above-referenced part numbers are described by GM as being 10" discs.

Notwithstanding the above, it's always been my understanding, perhaps incorrectly, that 1955 Corvettes with manual transmission were originally equipped with an 11" clutch.