I've got an auto '79 150. When shifting in/out of any of the gears I get a heavy "KLUNK". Is this my universal joints going bad?

Also, my drive gears of D, 1 & 2 are all very close together and not spread equally apart anymore so it can be hard to tell which gear I'm in if not paying close attention.

I usually get parts on rockauto.com but there are 15 different types of u-joints available and I have no idea what I need exactly. Both u-joints? Is there anything specific I need to know about replacing these?

 

Oh c'mon! Nothing?

 

Its best to take one in as a sample. In your case, if you are changing both, take both. Back in those days the rear joint sometimes had different size caps, the cap going to the diff yoke was bigger. To check joints for good or bad, first put tranny in neutral, then check for loosness, second, drop driveshaft and rotate or swivel the joint back and forth, checking for tight spots. Either is a sign of pending failure.

 

Thanks. I think I'm going to replace both, just because. I'll take both in to get matched just so I know it's right from the get-go.

 

i have the same noise coming from my 85 f150 when i shift from drive to reverse. It is a heavy metal on metal sounding clunk and also when driving i sometimes hear nasty rattling coming from there. Any suggestions?

 

just a thought..I had the same clunk on my 78 f150 custom. I took it to the tranny shop for a leaky pan gasket. they told me the clunk is just gear slop in rear end. however after they repalced the gasket, rear seal on trans and adjusted the bands and flushed the trans fluid the cluck is now gone.

 

The clunk is a result of ALL the play in the drivetrain. Not just one piece or another. Also, when your u-joints go bad you will get a vibration while driving. It will get worse the faster you go. If your u-joints had enough slop to "clunk" you wouldn't be able to drive faster than 5 mph. Your entire truck would shake so bad it will blur your vision. Check all the motor and trns mount and carrier bearing.