Rear End "clunk"?
Thread Starter
Melting Slicks
Joined: Dec 2003
Posts: 2,941
Likes: 1
From: Fidalgo Island Wa
Rear End "clunk"?
Rear End "Clunk"!
When starting cold,I have to wait for my '79 to completely warm up,& the RPM's to drop down to below 1200, or when I try to put it in reverse before then I get a loud -clunk!-sound.I'm not sure if its u-joints,or what?,and would like some suggestions.I've replaced a rubber "doughnut" thats in front of the rear end that helped some.I'm hoping I dont have to tear into the rear end or tranny.When its warmed up & idly normally,its noticeable,but barely
:mad :cry
When starting cold,I have to wait for my '79 to completely warm up,& the RPM's to drop down to below 1200, or when I try to put it in reverse before then I get a loud -clunk!-sound.I'm not sure if its u-joints,or what?,and would like some suggestions.I've replaced a rubber "doughnut" thats in front of the rear end that helped some.I'm hoping I dont have to tear into the rear end or tranny.When its warmed up & idly normally,its noticeable,but barely
:mad :cry
Racer
Joined: Jan 2002
Posts: 308
Likes: 0
From: central square NY
Re: Rear End "clunk"? (redson)
well if its not as nticable when your rpm's go down you know its in the driveline connected to the engine somehow. id bet your problum is in the tranny. probly a syncro, hope im wrong thou...... :blueangel:
Safety Car
Joined: Jul 2002
Posts: 4,269
Likes: 3
From: St. Charles IL
Cruise-In 5-6-7-8-9-11-12 Veteran
A CI-6 Car Show Winner
Re: Rear End "clunk"? (redson)
Check all the drive-line u-joints (half shafts and drive shaft) by twisting on them in opposte directions. Any play is reject and they should be replaced. If they are all okay (it only takes one bad one to be noisy) then it's time to drop the rear end for inspection. Excessive end play on the rear end spindles is a good indication of problems starting without removal.
Burning Brakes
Joined: Sep 2000
Posts: 922
Likes: 0
From: Maine
Re: Rear End "clunk"? (Big Fish)
What does it do if you push on the brake pedal very hard before shifting? Mine made the same sort of noise even after changing the differential donuts out (I was *sure* that was the problem) but doesn't clunk if I push hard on the brakes. The brakes have been redone but for some reason pushing harder stops the noise when shifting.
[Modified by Frank75, 8:01 AM 4/11/2004]
[Modified by Frank75, 8:01 AM 4/11/2004]
Instructor
Joined: Nov 2002
Posts: 183
Likes: 0
From: Stockholm, Sweden
Re: Rear End "clunk"? (Frank75)
Mine also has a "huge" and very irritating clunk when going from neutral or park to either reverse or drive. The solution, drop the idle to 600 rpm, then it's completely quiet but a hell to start since I have no choke ;)
I'm interested in seeing what you come up for a solution if you do, please post again if so. It doesn't bother me much now when I've lowered the idle but before, when the idle was around 750-800 rpm it was no fun.
I'm interested in seeing what you come up for a solution if you do, please post again if so. It doesn't bother me much now when I've lowered the idle but before, when the idle was around 750-800 rpm it was no fun.
Advanced
Joined: Apr 2002
Posts: 73
Likes: 0
From: Indianapolis IN
Re: Rear End "clunk"? (isosceles)
I had the same problem. It was really noticeable when going into reverse and especially when down shifting. It turned out to be a rubber bushing called a "snubber".
If you do a search, you'll find a thread that I started not too long ago w/ the exact same problem. There will be a link there to show you where it's at, where to order it, and how to change it.
:yesnod:
If you do a search, you'll find a thread that I started not too long ago w/ the exact same problem. There will be a link there to show you where it's at, where to order it, and how to change it.
:yesnod:
Thread Starter
Melting Slicks
Joined: Dec 2003
Posts: 2,941
Likes: 1
From: Fidalgo Island Wa
Re: Rear End "clunk"? (OREO Speedwagon)
I had the same problem. It was really noticeable when going into reverse and especially when down shifting. It turned out to be a rubber bushing called a "snubber".
If you do a search, you'll find a thread that I started not too long ago w/ the exact same problem. There will be a link there to show you where it's at, where to order it, and how to change it.
--->>I'm afraid that I changed the "snubber",or donut,or whatever it is no longer than 1.5 months ago,just for this reason.It made a very slight improvement for a very slight amount of time.I'm thinking of replaceing the u-joints anyway with Spicers,and someone mentioned checking the C-clips in the axle,also.I hope I dont have to break into the tranny.I say "I",but I'll have to have someone do that for me.Sounds like I better start making more money!
:yesnod:
If you do a search, you'll find a thread that I started not too long ago w/ the exact same problem. There will be a link there to show you where it's at, where to order it, and how to change it.
--->>I'm afraid that I changed the "snubber",or donut,or whatever it is no longer than 1.5 months ago,just for this reason.It made a very slight improvement for a very slight amount of time.I'm thinking of replaceing the u-joints anyway with Spicers,and someone mentioned checking the C-clips in the axle,also.I hope I dont have to break into the tranny.I say "I",but I'll have to have someone do that for me.Sounds like I better start making more money!
:yesnod:
[Modified by redson, 6:48 PM 4/11/2004]
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Instructor
Joined: Nov 2002
Posts: 183
Likes: 0
From: Stockholm, Sweden
Re: Rear End "clunk"? (OREO Speedwagon)
I had the same problem. It was really noticeable when going into reverse and especially when down shifting. It turned out to be a rubber bushing called a "snubber".
If you do a search, you'll find a thread that I started not too long ago w/ the exact same problem. There will be a link there to show you where it's at, where to order it, and how to change it.
:yesnod:
If you do a search, you'll find a thread that I started not too long ago w/ the exact same problem. There will be a link there to show you where it's at, where to order it, and how to change it.
:yesnod:
Drifting
Joined: Aug 2002
Posts: 1,731
Likes: 22
From: Marietta Ga.
Re: Rear End "clunk"? (desi)
:iagree: But here's another idea, my '72 automatic had the same problem and I did the front bushing with a rubber replacement, no improvement. Suspected u-joints and took the car to my mechanic to replace them all and rebuild t-arms, etc. He said that what he thought was making the clunk was a shot bushing on one of the t-arms. Mine is cured, so have someone try to see if they can see any play in the front area of the t-arms, if all else is checked. Also, he replaced the rubber bushing I installed with a polyurethane, because he felt the rubber one would still give too much.
Thread Starter
Melting Slicks
Joined: Dec 2003
Posts: 2,941
Likes: 1
From: Fidalgo Island Wa
Re: Rear End "clunk"? (72GACRZR)
:iagree: But here's another idea, my '72 automatic had the same problem and I did the front bushing with a rubber replacement, no improvement. Suspected u-joints and took the car to my mechanic to replace them all and rebuild t-arms, etc. He said that what he thought was making the clunk was a shot bushing on one of the t-arms. Mine is cured, so have someone try to see if they can see any play in the front area of the t-arms, if all else is checked. Also, he replaced the rubber bushing I installed with a polyurethane, because he felt the rubber one would still give too much.
[Modified by redson, 5:18 AM 4/12/2004]
[Modified by redson, 5:19 AM 4/12/2004]
Instructor
Joined: Nov 2002
Posts: 183
Likes: 0
From: Stockholm, Sweden
Re: Rear End "clunk"? (desi)
someone have link or title for the post :confused: please post, I have the same problem. :cheers:
I think that's the page you're looking for.
I'm going to start her up in a few hours and look at the snubber while someone else puts it into gear and see if it moves.
Drifting
Joined: Aug 2000
Posts: 1,758
Likes: 4
From: Medford, Or
Re: Rear End "clunk"? (OREO Speedwagon)
I had the same problem. It was really noticeable when going into reverse and especially when down shifting. It turned out to be a rubber bushing called a "snubber".
Dan
Thread Starter
Melting Slicks
Joined: Dec 2003
Posts: 2,941
Likes: 1
From: Fidalgo Island Wa
Re: Rear End "clunk"? (72GACRZR)
.Poly bushing? Where can I get one?
I believe he gets his parts from Volunteer Vette parts, see left side bar.
I believe he gets his parts from Volunteer Vette parts, see left side bar.
[Modified by redson, 12:24 AM 4/14/2004]
Burning Brakes
Joined: Sep 2000
Posts: 922
Likes: 0
From: Maine
Re: Rear End "clunk"? (redson)
FWIW, my car has new poly T/A bushings and it still clunked (worse when going into reverse). New snubber bushings helped somewhat but pushing hard on the brakes eliminates it (at least I can't hear it any more).
Thread Starter
Melting Slicks
Joined: Dec 2003
Posts: 2,941
Likes: 1
From: Fidalgo Island Wa
Re: Rear End "clunk"? (Frank75)
FWIW, my car has new poly T/A bushings and it still clunked (worse when going into reverse). New snubber bushings helped somewhat but pushing hard on the brakes eliminates it (at least I can't hear it any more).
