Thread: 68 chevy Sb 307 3spd.

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I will be replacing the clutch in my old truck. This will be the first time for me and I was wondering if anyone had any suggestions on this to make it go smoothly. I do not have any directions im simply just going for it..Lol

Be sure to find a clutch pilot shaft before you start the job. Any parts store will have a plastic one. An old trans front shaft works if you have one. The clutch is a bear to line up without one.

u mean clutch tool..?

You will want to possibly do more than just replace the clutch plate itself. You may also want to do the pressure plate and throwout bearing while you are in there. First of all, you want to sort of loosen all of the pressure plate bolts a little at a time, going around in a criss cross pattern, so that you don't warp the old one, in case it is going to be reused. Then inspect everything for crazing and heat cracks. Try to determine what wore out the old clutch, is it just age, or did oil get on it from a bad rear seal? Then look at the face of the flywheel for scoring and crazing. It may need resurfaced because the area where the clutch rides can get countersunk slightly from years of engaging and disengaging. If this is the case, the pressure plate won't be able to "clamp" the new plate tight enough, and it can start to slip.

I like to replace everything in there while I am at it. I only want to benchpress that tranny once. Get a motor manual for your car as it will show the proper torque specs for all the flywheel and pressure plate bolts. I use locktite on all of these bolts, and once again, go around the pressure plate in a criss cross pattern, tightening up each bolt a little at a time so as not to warp the pressure plate. Use an alignment tool, avail for like $ 5.00 at any auto store (there are different ones for different transmissions) and slightly pick up on it while tightening the pressure plate down because they are plastic and tend to sag a little, giving you a misalignment situation.

Then, take two long bolts, about 4 inches or more, that will screw into the holes where your trans bolts to the bell housing, and cut their heads off and screw them into the top two holes (where you would normally put bolts to secure the trans to the bell housing) This will make you a "ramp" to guide the transmission into the pilot bearing and clutch plate. Just lift your trans up and put the top two holes of the trans over these ramp bolts and start to slide it in place. You may have to wiggle it a little and even put the trans into a gear and turn the output shaft slightly to get it to engage the clutch and finally seat into the pilot bearing. DO NOT FORCE IT, you will bend stuff. Once the trans if dead flush against the bell housing insert the regular bottom two bolts and then replace the ramp bolts with the regular two top bolts.

The explanation above is simplistic, but just take your time and check all the parts for wear and make sure you torque everything with a good torque wrench.

Have fun (as if this job could ever BE fun)


Don


PS: You are dealing with lifting a heavy chunk of cast iron over your body, so obviously take your time to keep you from being hurt. Block up the car on good jackstands and get someone to help you. This is not a job for one person.

Man that is about as realistic as it gets!! I really appreciate the responses and thank you. This is the exact reason i signed up in ClubHotRod.com. I will use your wisdom and experience to my advantage. THANK YOU!

I used to change those little 3-speeds in a snowbank in the middle of the road in about twenty minutes, hold 'er up with my left hand and put the bolts in with the right. Hardly be late for school!

Originally Posted by R Pope

I used to change those little 3-speeds in a snowbank in the middle of the road in about twenty minutes, hold 'er up with my left hand and put the bolts in with the right. Hardly be late for school!

That's what I call "pumping iron".

Originally Posted by R Pope

I used to change those little 3-speeds in a snowbank in the middle of the road in about twenty minutes, hold 'er up with my left hand and put the bolts in with the right. Hardly be late for school!

Me too. I had a '63 Bonneville with a 389, and I put tripower from a '64 GTO on it and a 421 cam. I couldn't afford a 4 speed, so I ran 3 speeds. 2nd gear would always blow after a few power shifts, so I kept a spare in the trunk ($ 15.00 was the going price at the junk yards) I got so good at changing transmissions I could do it while out on a date. I would pull the front wheels up on a high curb like at a Dairy Queen, and slide under and change transmissions in about 15-20 minutes. I kept coveralls in the trunk and a carpet, and knew exactly what wrenches to take under with me.

If I was lucky, my date was still there when I got done.


Don