77 trailing arm
Thread Starter
2nd Gear
Joined: Oct 2014
Posts: 2
Likes: 0
77 trailing arm
I'm new to vets and got a question and need some input. 77 Vette I was getting a pop noise coming from the rear end. I couldn't find anything when I jacked it up. Notice while in the air I started and put in gear and the passenger side was trail arm was jumping like the was something out of balance. I put jack under the shock support and start raising it up more pressure I put on the less it wanted jump. What could be causing this. Any help would be nice.
Melting Slicks
Joined: Oct 2011
Posts: 3,453
Likes: 67
From: Midland Ontario
NCM Sinkhole Donor
Welcome to the forum, I remember my first post. You don't want to run your car while on jack stands. The suspension hangs, and causes the u joints to bind - that's why it stopped as you jacked up the trailing arm. Check your differential fluid level; if low or dirty, replace it and add GM posi additive. Then do some low speed figure 8's to work the fluid into the clutches. See if this works for you.
Thread Starter
2nd Gear
Joined: Oct 2014
Posts: 2
Likes: 0
Welcome to the forum, I remember my first post. You don't want to run your car while on jack stands. The suspension hangs, and causes the u joints to bind - that's why it stopped as you jacked up the trailing arm. Check your differential fluid level; if low or dirty, replace it and add GM posi additive. Then do some low speed figure 8's to work the fluid into the clutches. See if this works for you.
Last edited by hazelrigg74; Oct 20, 2014 at 12:38 PM. Reason: Forgot something
Melting Slicks
Joined: Oct 2011
Posts: 3,453
Likes: 67
From: Midland Ontario
NCM Sinkhole Donor
Like many here; if your rear end has had no major service since new, your stub axles have worn at their ends to the point where the c-clips may not be holding them in place any more. A major service is probably due.....but be careful how you proceed at this point of ownership. First off, if this car is to be used as a weekend cruiser and stored six months of the year as mine is - with maybe 1000-1500 miles a year put on it, then maybe you don't want to go there until absolutely necessary. If you're going to be undertaking a major frame off, then dive right in. You'll get a lot of responses to your dilemma, but first see if a fluid change has any effect on the issue. It's cheap and relatively easy to do. You need to suck the fluid out of the filler hole, as no drain plug exists. Your local auto parts store should have a hand pump to do this. I also recommend picking up some service literature, namely the Assembly Manual (AIM) and Service Manual (the bible the mechanics used when servicing the car). These are invaluable, even if you choose to have a mechanic do all the work, since you'll understand what the process is you're being charged for. Good luck.
