Question #24526

TH350/454 not shifting to second?

1983 Chevy truck 454/350 it was shifting fine for a while but sat for likea month then tried her out again and no shifts. goes into drive and reverse fine but just cruises around at 20mph and when u try to gas it the rpms pick up but second gear never kicks in. I’ve checked the governor and it’s like new, nothing...

  • bo

need 16-18 pounds of vacuum at the modulator. don't have it find the vacuum leak. if its good next step the governor. that ok then internal

  • Kenny

well pretty much know what you are doing. Only thing I can see is the vacuum source good?

  • CB

Look for a vacuum leak there should be a vacuum tube off the carb and back toward the transmission (plugs into a line coming up from the tranny), if it is cracked or has pulled off it can cause a myriad of shifting symptoms - easy and free to check and test.

  • Anonymous

Check for a vacuum leak. Check for a bad throttle cable. If everything checks good, tranmission is likely done.