Clunk noise in rear

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Steve Crist
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Clunk noise in rear

#1 Post by Steve Crist »

1963 B Super. Only 50 miles after being completely restored. Car runs great but one problem I can’t sort out. When coming to a stop or backing out of the garbage over the expansion joint there are 1-2 subtle clunk noises in the left rear. This doesn’t happen at speed, even over road bumps.

Background: Vic rebuilt the transmission (kudos to Vic, an excellent job, the car drives and shifts perfectly). I replaced the clutch, and clutch plate, throw out bearing, engine mounts, torsion bar bushings.

Here’s what I’ve done so far:

Calculated and replaced axle bearing shims
Replaced axle tube gaskets
New Koni shocks
Torqued axle nut to 396#
Checked wheel nuts and splines

What I plan to do next:
Pull out torsion bars and check bushings

Didn’t see anything in archives so am hoping someone has advice.
Thanks, Steve

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Jim Clement
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Re: Clunk noise in rear

#2 Post by Jim Clement »

how about a missing bushing rubber at the top of the shock absorber.
this will cause the top of the strut.. the threaded part to hit the body ..
this happened to me after I put everything (almost everything) back together again...
 

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Juha Vane
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Re: Clunk noise in rear

#3 Post by Juha Vane »

Check the bolts that hold swing arms in axle tubes.
KTF,

Juha Vane
Finland

'59 308
'63 356
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Norm Miller
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Re: Clunk noise in rear

#4 Post by Norm Miller »

If your car has a factory camber compensator it could be the culprit. The bolts (hangers) tend to do that.
 

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Juha Vane
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Re: Clunk noise in rear

#5 Post by Juha Vane »

What was the reason for this "clunk"?
KTF,

Juha Vane
Finland

'59 308
'63 356
'85 911

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David Jones
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Re: Clunk noise in rear

#6 Post by David Jones »

Another cause of rear end clunking is if the 4 bolts holding the brake backplate to the axle are not torqued down sufficiently. Every time you apply the brakes or accelerate the backplate will tend to rotate causing the clunk.
If I had known I would live this long I would have pushed the envelope a little harder.
Cymru am byth
David Jones #9715

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Vic Skirmants
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Re: Clunk noise in rear

#7 Post by Vic Skirmants »

And that is why one does not put too many shims in the bearing cover. You have to clamp the backing plate, you are NOT clamping the bearing!
The shims merely take up any extra space so the bearing does not "walk" side-to-side. Unfortunately, the manual is confusing, and sounds like you have to "preload" the bearing; NOT.

Steve Crist
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Location: Portland, OR

Re: Clunk noise in rear

#8 Post by Steve Crist »

Thanks everyone for your ideas and input. Here’s an update:

I noticed lateral play in the rear wheel so I reduced the size of the flange gaskets from 0.2 mm to 0.15 mm.
Re-checked the swing arm bolts, re-greased the torsion bar splines (inside and out).
Re-calculated the bearing shims & torqued the bearing cover backing plate to 42 ft lbs.

Once the weather improves, I’ll see if I’ve accomplished anything.
Thanks, Steve
 

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