That's what mine did when it went bad. Get a poly one..............
"Thud" noise with slight deceleration
Thread Starter
Drifting
Joined: Apr 2002
Posts: 1,720
Likes: 19
From: Manhattan Beach Ca
"Thud" noise with slight deceleration
When I'm cruising flat at constant pedal say 40 mph then back off the pedal to slow down slightly, I get this slamming thud sound from under or the back of the car. I thought maybe loose tranny support bolts but all look fine. Its like the change in RPM or steadyness causes something to jolt the drive system even though we're talking about slight changes. U-joints would be heard at takeoff and other times so I dont think its that.
I was thinking this would be something common someone else has heard before and might know right away.
I was thinking this would be something common someone else has heard before and might know right away.
Le Mans Master
Joined: Jan 2007
Posts: 8,012
Likes: 3,343
From: Omaha NE
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Thread Starter
Drifting
Joined: Apr 2002
Posts: 1,720
Likes: 19
From: Manhattan Beach Ca
I knew you guys would know. But I'm not familiar with this mount you're talking about. Are you talking where the driveshaft connects to the differential "yoke" area? I didnt even know a mount existed.
Drifting
Joined: Jul 2005
Posts: 1,591
Likes: 0
From: Oakville Ontario
Check out B, H and I. 
http://www.madvet.com/shop?frame=4.1433
I just had mine done and it solved the problem.
http://www.madvet.com/shop?frame=4.1433
I just had mine done and it solved the problem.
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Burning Brakes
Joined: Jan 2006
Posts: 1,154
Likes: 1
From: St Augustine FL
interesting thread. I hear a similar nois in my car but only at low speeds like when comming to a stop and the RPM drops to almost to idle speed. Kind of sounds/feels like a granny gear disengaging but not near as loud.
Thread Starter
Drifting
Joined: Apr 2002
Posts: 1,720
Likes: 19
From: Manhattan Beach Ca
Final update for the search people. I got my rubber parts from Zip and they were perfect replacements except for the Bolt. The bolt was too short and as some have said before, washers were understrength. So I used my existing bolt and nut combo. Definitely dont have to take driveshaft off, but it would make things easier. Hardest part is putting bolt back in from top. Driveshaft keeps bolt cocked just a hair so it wont go in. You have to use a good force on top of bolt to drive in. Jacking diff up a hair seem to help too. Fortunately my driveshaft balance weight was right there at bolt head and with wheels off ground I could spin the driveshaft and the little weight acted like a hammer and smashed/forced the bolt downward in the hole. Seemed too lucky. It's all good now.
Race Director
Joined: Feb 1999
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From: Lenoir City Tennessee
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Glad it was a pretty easy fix. Glad you came back and finished the thread with your solution. Maybe it will help someone in the future when the same happens to them.
I had the same problem with my 70 when I first got it. Seems this bushing takes a lot of abuse because there are several people on here that replace them.
I had the same problem with my 70 when I first got it. Seems this bushing takes a lot of abuse because there are several people on here that replace them.
