Tranny noise

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DriveCool77
Posts: 12
Joined: Fri Apr 24, 2015 5:11 pm

Tranny noise

Post by DriveCool77 »

I've started having a severe clunk only when shifting into reverse. I've crawled under and had a friend put it in gear to see if I could pinpoint it out of the case or the bell but it's so loud it's indeterminable to pinpoint. It shifts smooth through the gears and into drive just find without any harsh noise, only on the initial shift to reverse. Changed the fluid with no difference. U-joints are fine. Has anyone else had this? Thank you in advance

77 with a 351w
BirdShepherd
Posts: 229
Joined: Fri Mar 06, 2009 10:01 pm
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Re: Tranny noise

Post by BirdShepherd »

Your problem might not be with the transmission at all. When I engaged my 1979 Bird into gear many years ago, I also heard a clunk somewhere underneath the car. It turned out to be an easy fix.

Located under your axle are two rear suspension lower arms, one on each side. Each is attached to the frame on the front portion and to the rear axle on the rear portion of the arm. Each suspension arm is attached with pivot bolts. The bolts come loose with usage.

I put the impact wrench on the bolt making sure the nut on the other side was held in place with a open end wrench and tightened it up. The clunk sound was not heard again. You can still do it without an impact wrench. Use 3/4 drive ratchet and elbow grease!

Best wishes.
Shepherding 77-79 T-Birds, Shepherding People
DriveCool77
Posts: 12
Joined: Fri Apr 24, 2015 5:11 pm

Re: Tranny noise

Post by DriveCool77 »

Thanks for the idea. Finally got under there the other day and put some wrenches on it and they didn't budge. Hit every other bolt I could find under there with the same results. Gonna throw it up on a lift next and get the weight off the drive train and give that a shot. Any other ideas are still welcomed. Thank you.
BirdShepherd
Posts: 229
Joined: Fri Mar 06, 2009 10:01 pm
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Re: Tranny noise

Post by BirdShepherd »

I replaced my transmission mounts many years ago. The broken mounts did not make a clunking noise, per se, but nonetheless they were noisy while making a stop--until replacement. Cracked or broken motor mounts do the same.
Shepherding 77-79 T-Birds, Shepherding People
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