Clutch Sizing Questions
 

So it's time to replace the clutch on the '69. I have seen an array of sizes, etc. So, I have a few questions:

First off: Which do I need for a '69 c10, 1/2 ton, 2 wheel drive, 250 I6, 3 on the tree, power nothing.

Secondly: For future user's search purposes, if anyone knows a formula or resource that searchers can use in the future, would you mind sharing it? Maybe this can take the place of the multiple "what size do I need" threads I found when I searched.

Third: I went by the parts store and they said they listed 10", and 11" and they couldn't get one of them at all. Do they use the same pressure plate? If I had one and they only sold the other, could I use the one they could get? I.E. if I have 10, could I use the 11 without a problem (or vice versa)?

Thanks in advance for any help I can get.

Chris

Re: Clutch Sizing Questions
 

should be an an 11 inch clucth

Re: Clutch Sizing Questions
 

Get the 11'' in the diaphram style, same clamping pressure and easier on the linkage, and smoother operation

Re: Clutch Sizing Questions
 

For the 1/2 ton I- 6, you should have the 10" clutch. The 11" clutch wont fit the bolt pattern on that flywheel.....however, if you go to the smallblock flywheel, you can fit an 11 or 12" on it. Best of luck...:crazy: L

Re: Clutch Sizing Questions
 

I have a "heavy duty" clutch option on my K20 with a 250ci and a 3spd. I was told this meant I had a 12" clutch?

Can you elaborate on the "smoother operation" ?? Also, do heavy duty clutches come with stiffer pressure plates, or is it purely a clutch disc area kinda thing?

Re: Clutch Sizing Questions
 

The 250 inline 6 we removed from our 1970 C10 3 speed had an 11 inch clutch, same as most small block trucks. Get the pressure plate with the raised fingers and the short release bearing, better setup IMHO.

Re: Clutch Sizing Questions
 

I had a 71 C/10, 6 -250 with 3 spd & it was equipped with the 10" clutch. This was a "bare bones" truck, so it may be how it was ordered or optioned, that makes the difference? The flywheel was the same 14" diameter pc that the 11 & 12" plates fit on......but it was drilled differently. Tear it down ,to see what you have before ordering parts;) best of luck,:crazy: L

Re: Clutch Sizing Questions
 

Wow, thanks guys. I put it on a lift the other day and pulled the cover, and I *believe* it is an 11.

It seems odd that there is not some kind of pattern. At least not that anyone has found. Hmm, I guess I'll keep looking around.

Thanks again,
Chris