a friend of mine has a 1958 chevy apache,350 with a four speed,ever since he got it ,it has had a nasty shake when you let the clutch out in 1st gear from a dead stop,we have installed a new clutch and pressure plate,resurfaced the flywheel, I noticed that the center section of the rear end moves up and down quite a bit when it happens,shackles are all goot,looks like all the play is in the springs,you can see them flex quite a bit,could the problem be weak springs?any advice would be helpul,thanks,rob
Check the motor and transmission mounts and maybe replace them. They can get soft or break from age. I have had them look good but actually been separated when I removed them. Your springs could also be wrapping around the axle housing from torque. Pickup rear springs take a beating by people hauling heavy loads and they could have lost some of their tension. But I would start with the motor mounts. Don
Whenever you pull a clutch to chase a chatter, you need to use a dial indicator on the flywheel face, before and after resurface, I fixed a guys 66 c10 with same drivetrain about 3 years ago with the same chatter, A local trans place did a new clutch twice, cut it twice, then rebuilt the muncie, trying to cure it over a 2 year period. The guy brought me all new parts and a repro flywheel. First thing i did was use an indicator, on the old wheel and then the new wheel. The crank flange was bent enough to give 16 thou runout at the outer edge of the contact surface. there was no vibration in the motor, so I was not going to replace the crank; I took my time and hand dressed the flange to get it to 1.5 to 2 on the repro wheel. That wheel had highs and lows about 1.5, but after a few years has not chattered once.
i had one go so bad i couldn't drive the truck forward but noticed it did not do it when i went to back off the road. i drove home backwards...almost two miles
Dont forget to check for all the wear in all the clutch linkage. Bellcranks, pedal, rods, ect. Oblong holes, worn bushings, and rod pivot pins worn.
I had a car that had realy rough rear end gears, but, the shake was kept in check by sliding the clutch. To me it seems like the clutch is grabbing eraticaly kinda like a ceramic clutch disk would. I know if it doesn't get corrected its gonna cause other problems. The rear end movement is pretty normal with in reason with the chassis load and un load...
Does it have the SM420 4-speed? Normally those start off in 2nd gear. I'd try that first and see if it improves. But do what the other's suggest, go over all the mounts, center hanger bearing (interesting when those let go...), etc. Bob
If the mounts look and test OK I might try spring clamps on the forward section of the leafs. http://www.jegs.com/i/Mr.+Gasket/72...&cagpspn=pla&gclid=CK2X9YnU07YCFQef4AodEA0Avg Had a Volvo 240 with a lot of miles. the clutch was probably down to the rivets, but started chattered when starting off. The engine mounts on 240s are quite soft to hide the big 4 cylinder vibes. The engine can be rocked a lot sideways by hand. I installed a medium grade screen door closer between the engine lift loop and the strut tower. It pretty much killed the chatter.
OK,,I'm going to ask a what will sound like a Dumb question but please post the answer. How tall of a lowering block is he running in the back? The Wizzard
I just re-read the 1st post. Are the spring clamps still present? A few busted ones would let the leaves do the funky chicken. Bob
Had the same problem with a Nova. I replaced the pressure plate and clutch severl times and nothing fixed it. HERE IS WHAT I FOUND. Look at the part on the transmission that the throw out bearing slides on. My was worn to the point that the throw bearing was contacting the fingers on the pressure plate at an angle causing uneven prrsure and making the clutch chadder. Changed the $4.00 part and the problem went away. Good luck
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