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Discussion Starter · #1 ·
Hey guys I gotta question. I'm told by a fellow at that Ford produced a light duty, medium duty, and a heavy duty C4 tranny. The six bangers got the light duty, V8's got the medium duty, and police/taxis got the HD version. Any rebuttle?

Ok, so what was the difference? I have a C4 in my '68 that has a 200 attached to it. It was rebuilt in '98 by a tranny shop in San Diego. Next Wednesday I'm dropping in a very heftily built 250 six popper with a TCI Breakaway converter. I won't go into all the specs but I have a 4 barrel intake being casted for it currently and I have full confidence that I will be sitting pretty with high 14's in the 1/4 mile. Slicks will eventually be added this summer and I plan to run the hell out of it. All I've done to the tranny other than the converter is a B&M stage II shift kit.

I'm worried about breaking this little guy. When a tranny shop rebuilds one of these would they install 6 cyl specific parts? I know the case and the gears are the same but I think the servos, bands, and clutches were lighter than the V8 trannys. I wouldn't see much point in installing inferior parts though if it's the same amount of work.

Any input would be greatly appreciated. I'm going to get in touch with the tranny shop that rebuilt it later this week to get more details. Unfortunately, they send them off to be rebuilt so I'm not sure if they will be willing to provide me with any info. Thanks


[color:blue]'68 Coupe
250/C4, 221 Argentine Head
Breakaway Converter, 9", 3.50's/T-lock</font color=blue>

307 Posts
I have the heavy duty that came out of a truck. It has one extra clutch than the other two trannys. I don't know the difference between the light and medium duty trannys.

'68 Coupe, 289, C4, 3.40 gears, GT-40P heads, TCI Streetfighter stall convertor.
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