1977L48

Noticed this a few days ago, while turning at any speed there is a poping noise comming from the back of my 77. Any ideas? At slow speeds there is a small shimmy. Any imput would be great

MelWff

Check the universal joints, the rear wheel bearings, the fluid level in the rear, the side yoke end play.

77vetteluva

Does it happen when it's cold or only after you've driven a bit? If it's when it is warmed up it could point to rear end fluid. Change it and make sure to add posi-trac differential additive. This solved a noise for me that sounded like the car was coming apart. Especially when accelerating from a stop while turning. Let us know what you find.
-Rick

1977L48

Thanks, and yes its only after ive been driving for say 20-30 min. Ill czech it today

1977L48

Ok so changed fluid, old stuff looked, well old, but 75-90 royal purple in it with 8oz of gm posi additive. We will see how it acts in the morning

1977L48

sound gone, thanks!

77vetteluva

Glad to hear the noise is gone....as if that made any sense!

1977L48

well it seemed alittle low when i started sucking out the old stuff, but i was told years ago by a vette guy that after you change the diff fluid to go in a tight circle in a parking lot at slow speeds to get the new oil to the bearings? is this true or has anyone done this before?

Danish Shark

It's true, though it's not for the bearings but for the clutch plates in the positraction unit.