Problems with grinding noise at acceleration
Thread Starter
6th Gear
Joined: Sep 2009
Posts: 6
Likes: 0
Problems with grinding noise at acceleration
My dad has a 1979 corvette L48 Automatic that is completely stock and it runs really well except if you step on the accelerator from a stand still light at an intersection. So basically it is impossible to squeal tires if you had/wanted to. There is a grinding noise from the center of the vehicle but i have yet to figure out if it is in the front or rear. You can feel the grind as well. We had our mechanic check out the flex plate in the tranny but it was fine. I don't know much about mechanical stuff except how to change basic things like fluids, brakes, basically dummy work. The car runs fine and the tranny shifts smooth and on time when you're on the road. If anyone has any ideas as to what this noise could be coming from please let me know it's getting really frustrating.
Thread Starter
6th Gear
Joined: Sep 2009
Posts: 6
Likes: 0
hmmm the brake thing sounds possible because they tend to creak a little and stick in situations like pulling into the driveway. And yeah the L48 doesn't have much punch. It's too quiet and has doesn't have much power but looks cool.
Le Mans Master
Joined: Jul 2009
Posts: 6,647
Likes: 1
From: East Aurora N.Y.
St. Jude Donor '10
My dad has a 1979 corvette L48 Automatic that is completely stock and it runs really well except if you step on the accelerator from a stand still light at an intersection. So basically it is impossible to squeal tires if you had/wanted to. There is a grinding noise from the center of the vehicle but i have yet to figure out if it is in the front or rear. You can feel the grind as well. We had our mechanic check out the flex plate in the tranny but it was fine. I don't know much about mechanical stuff except how to change basic things like fluids, brakes, basically dummy work. The car runs fine and the tranny shifts smooth and on time when you're on the road. If anyone has any ideas as to what this noise could be coming from please let me know it's getting really frustrating.
Thread Starter
6th Gear
Joined: Sep 2009
Posts: 6
Likes: 0
it's every once in awhile usually if you are stopped on an incline or there is more stress against the vehicle and it requires more of a punch to get it going. We thought it sounded like it was coming from the flywheel (flexplate since its an auto) , but when the garage looked at it, there was nothing wrong with the plate and everything looked alright at the time.
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Le Mans Master
Joined: Jul 2009
Posts: 6,647
Likes: 1
From: East Aurora N.Y.
St. Jude Donor '10
it's every once in awhile usually if you are stopped on an incline or there is more stress against the vehicle and it requires more of a punch to get it going. We thought it sounded like it was coming from the flywheel (flexplate since its an auto) , but when the garage looked at it, there was nothing wrong with the plate and everything looked alright at the time.
Le Mans Master
Joined: Jan 2000
Posts: 8,918
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From: New Hill NC
That year is also notorious for eating yokes and grinding them up in the rear. Along with that comes wear in the posi clutches. So if these strange noises usually occur after it has been driven for a while, I would guess that is the problem.
Le Mans Master
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From: New Hill NC
Race Director
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Could be the trans output yoke hitting the old transmission tunnel insulation. Could also be the trans output yoke hitting the emergency brake roller in the front of the trans tunnel. What kind of shape are the motor mounts and the trans mount in. If they are worn, they could allow enough movement to let the above happen.
Then again, I am just guessing.
Then again, I am just guessing.
