Need some help!
Thread Starter
Intermediate
Joined: Jun 2008
Posts: 30
Likes: 0
From: Chesterfield VA
Need some help!
Okay I know it is pretty tuff diagnosing sounds over the internet but I will try for some help anyway. My 79 vette is making a groaning/ rubbing type sound from underneath when I drive. I thought brakes at first, but it does not pull to one side or the other like a brake caliper is sticking. I cannot tell if it is from the front or back. I checked the Rear Diff fluid, it is full. I jacked up the rear end, started it up and drove. No noise. The mechanic that inspected it for me when I bought it told me that all the bushings would need to be replaced, the automatic transmission is leaking slightly from the pan seal, and the oil pan is leaking slightly from the front pan seal. I have replaced all the power steering hoses and refilled the fluid. Oil and Trans fluid are all good. I first noticed the sound when i pulled into my garage. I can hear it forward/ reverse and going slow and fast. I am afraid to drive it to far because i do not want to make things worse. The closest mechanic is about 15 miles away. Any advise??? Thanks!!
Instructor
Joined: Sep 2006
Posts: 211
Likes: 0
From: Searcy Arkansas
Your right about it being hard to figure out noises on line..... Anyway... it is going to be much easier to figure out if you can decide if it is front or back end noise... Front end is usually tire rub, which you would probably notice more when turning unless they are just crazy wide/tall... or could be a bad bearing(s)
There is more that could be going on with the rear... if aftermarket wheels, you could be rubbing the e-brake cable bracket or brake caliper if the wheel is not back spaced correctly. My 78 had a parking brake spring come lose and wedged between the brake shoe & drum... It made a very loud rubbing/scraping noise in forward or reverse... Could also be an issue with the differential itself...
I guess the first thing is to figure out what end of the car it is coming from...
There is more that could be going on with the rear... if aftermarket wheels, you could be rubbing the e-brake cable bracket or brake caliper if the wheel is not back spaced correctly. My 78 had a parking brake spring come lose and wedged between the brake shoe & drum... It made a very loud rubbing/scraping noise in forward or reverse... Could also be an issue with the differential itself...
I guess the first thing is to figure out what end of the car it is coming from...
Thread Starter
Intermediate
Joined: Jun 2008
Posts: 30
Likes: 0
From: Chesterfield VA
the tires that are on it are Supreme TR Sigma P225/ 70R15 100T the rim width is 6.5. I was told they are not vette tires but they are pretty much brand new so I will keep them on till I can fix other issues first. I measured the width of the tire itself at a little less than 9 inches.
Pro
Joined: Jul 2008
Posts: 660
Likes: 1
From: Springfield Tennessee
St. Jude Donor '09
If it's a constant noise, if it were the tires seems you would be able to see markings on the tires. Look on the insides too. If you have any way to get under the car look for places that have been rubbing, it should stand out pretty well. As far as the brakes, if one of the pads have come loose or is hanging up without retracting all the way that could be it.
Like you mentioned, hard to say on the net, just throwing out a few things I'd check first.
Like you mentioned, hard to say on the net, just throwing out a few things I'd check first.
CF Community Team
Joined: Oct 2004
Posts: 19,341
Likes: 5,232
From: Cape Cod, Mass.
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Check your rear wheel bearings.
