Hello! I have a 1971 Maverick 302. I just had my C4 rebuilt and my flexplate replaced and I am noticing a lot of vibration. The whole car vibrates when I'm idling, when I'm accelerating and when I'm traveling up hill. I realized the up-hill vibration is not new. This vibration is a pulsing type, it seems to pulse more frequently at higher RPMs. I can't feel any pulsing below 40 mph. I can feel the acceleration vibration in the steering wheel. Does anyone have any idea what is causing these types of vibrations? Could it be my U-joints? I've replaced my under arms and upgraded the front end to manual disk brakes.
U-joints won't make one vibrate at idle & should not vibrate going up hill... If engine isn't missing(bad plug, wires etc), and it didn't vibrate prior, has to be related to trans rebuild... Wrong flexplate or maybe converter issue as already suggested are the the mostly likely causes.. What balance factor is this flexplate?? If it's a 50oz there's your problem, earlier than '81 302 require a 28oz...
I was thinking it may be the flexplate. I had my mechanic put a new one in. I ordered the TCI-529618. Its a 157 tooth, 10.5" bolt pattern, 28oz externally balanced flexplate. It should be the right one. He also put in a rebuilt torque converter from Superior Torque Converters. Its supposed to be an 1800-2000 stall. Other than that, I don't know much about it. The engine isn't misfiring and it only had the pulsing vibration (at over 40mph) before the rebuild. It must be the converter.
My motor is also squealing near the fan. It squeals when I rev the motor really quick and it was doing that before the rebuild. I thought it was the water pump, but maybe it is the harmonic balance. It vibrates the most when I romp on the gas.
I removed the belts and by process of elimination, I've narrowed the source of the squealing down to the power steering pump and the water pump. I think its the water pump. Since I may have to have the harmonic balance replaced, I may have them replace that as well.
