differance between a c4 and c6 tranny???

[johnny79]

im thinking of converting my truck to automatic, i would like to know the differance betwwen a c4 and a c6 transmission, thanks.

 

[cipsmithers]

lollers, double thread fail

 

[Fellro]

Differences would be length, durability, output shaft.The output shaft is larger on a C6, the C6 is more durable, and is the longer of the two. You can find C6's in all engine configurations since the 60's.

 

[LEB Ben]

You can find C6's in all engine configurations since the 60's.

I was gonna ask...wouldn't his engine choice dictate what tranny he chose? SB=either tranny but BB=C6.

 

[Fellro]

That would also be true, yes.

 

[mtflat]

Engine size can be important. Rule of thumb from the hotrodders where hp loss is factor:

C6 uses in the neighborhood of 65 horses to get things moving from a dead start. C4 uses about half that.

Once moving, all things are more or less equal.

 

[bucks77ford]

You an use a C4 for a big block, but it would have to be upgraded and also have the 351/400 bellhousing where as a stock C6 would be just fine.

 

[TexasRho83]

Plus, C6's have a good rep for holding up well...especially when beefed up. Coupled with an NP205 cast iron case, you'd have a pretty hardy setup

 

[SuperCab]

I was gonna ask...wouldn't his engine choice dictate what tranny he chose? SB=either tranny but BB=C6.

That's the biggest factor. FE (360,390,428) , 335 (351M, 400) , 385 (429, 460) = C6 only


C6's are built heavier than C4's and therefore are prefered for trailer towing, 4x4, drag racing type applications that would grenade a stock C4.

The gear ratio spacing is better in the C4 though, and they can be built to take hundreds of horse power. But SBF pattern only without an adaptor plate or something.



What kind of project do you have in mind?

 

[LEB Ben]

Yo Matt...don't forget about the FMX tranny...while extremely rare, wasn't that basically a C4 that would bolt to a 335 or 385. Just figured I'd show you the err of your ways...haha.

 

[bucks77ford]

I'd also think about the AOD for a truck with a 302 and used mainly for cruising.

 

[johnny79]

well i have a built 351m and need something that will hold up to the abuse of my 44's, c6 it is! thanks fellas

 

[Fellro]

Yo Matt...don't forget about the FMX tranny...while extremely rare, wasn't that basically a C4 that would bolt to a 335 or 385. Just figured I'd show you the err of your ways...haha.

FMX trannies did come behind the 351M/400, but I don't think they shared a thing with the C4, they had a cast iron center case and a removable bell. They were pretty common in the 70's T-birds and Cougars. They weren't really known for their durability...