6T7L71CPE

I've been trying to track down some rattling I get going over bumps. A little tightening of exhaust bolts helped but I still have something making occasional noise in the back somewhere. I rebuilt the whole suspension 20+ years ago, BF (Before Forum). So, not having the massive knowledge base of the Forum I used mostly polyurethane products being influenced by certain catalogs... Here's what I found, cracked poly rear spring bushings. I can't tell that the spring is hitting the bolt but it's close. I was checking the body mounts too and found that the original rubber is still pliable! Yes, that's a 7 leaf spring, another BF indiscretion. LOL

Bluestripe67

I wouldn't think the spring bolts etc would make "rattling sounds. Something more like clunking/banging solid sounds. Have you checked the upper shock mounts, the gas tank straps, brake lines and attaching clips, e-brake cables, pinion mount bolts. Check 'em out. Dennis

67TBowl

Another thing to check are the exhaust clamps that hold the exhaust tips on. They can rub on the exhaust bezels that go thru the lower rear panel. Mine have enough clearance when the pipes are cold but when the pipes heat up there seems to be enough expansion to cause rubbing.

I have also had squeaking from my lower shock mounts. If I remember correctly, I just loosened them, sprayed some silicone in and retightened.

Good Luck,
Mark

6T7L71CPE

Thanks for the input.
Bluestripe67, My rattling is more like the sound when an exhaust pipe hits the frame/spare carrier or crossmember. So, Clunking/Banging is a better description. I tightened the pipe clamps which seemed to help a creaking that sounded similar.

67TBowl, I don't have Tips or Bezels, the welded tips exit below the panel. I've got great clearance everywhere. I pulled the passenger shock off, it and the mounts (had grease) seem fine, need to do the driver side. I jacked the car up and it appears the spring was touching the spring bolt on the passenger side, which is where the sound seems to be coming from. But, not sure it would like what I'm hearing, but, could be. The poly strut bushing are SHOT TOO!

MiguelsC2

Your spring bushings are missing the cup at the spring. Thats why it tore up your bushings.

I have since changed the spring color and now use the GM rear sway bar and links. But this will give you an idea.

Bluestripe67

[QUOTE=MiguelsC2;1581098214]Your spring bushings are missing the cup at the spring. Thats why it tore up your bushings.

I see it and Dennis

6T7L71CPE

True, there is no cup, but these are polyurethane bushings that wouldn't conform to the cup anyway. I'm thinking it wouldn't have made a difference since the strut bushings are doing the same thing.

6T7L71CPE

Addendum: I agree the bolt might not be hitting the spring if it had a cup to center it. I looked through the parts I pulled off way back when and the spring doesn't have an attached cup (might be C3 I'm thinking of) nor did I have any left over in the my old parts box. I'll be buying them along with new RUBBER bushings! Thanks

MiguelsC2

C3 had the same cups.

ikkarus1

So is there a consensus, that polyurethane bushings are not the best thing to use if you are rebuilding your suspension?

midyearvette

you will get opinions all over the place on this issue
i have polys in the rear and standard rubber on the front end components
however, nothing will work correctly without the proper hardware (washers etc.)....in either case
i really like the polys on my rear spring and have no wear issues....

TheSaint

I would use the cups just like it is on the picture. Both the polyurethane and rubber bushings are supposed to have the cups on each side of the bushing

MiguelsC2

Actually the cup is on the spring side and control arm only. A washer is used on the bottom.

Your diagram doesn't show one being used in the control arm. Not sure if it's supposed to? My kit came with 4. So thats how I used it.

JohnZ

There are two peened cups on each side - one on the spring, and one in the end of the trailing arm.

Mike67nv

Here's a link to an earlier thread showing the cups swaged on the control arm and leaf spring:

http://forums.corvetteforum.com/c1-a...af-spring.html

6T7L71CPE

John, Mike,
This tells me that the 9 leaf spring I replaced wasn't original as I assumed. I just looked at it and no sign of the cups being peened/swaged like I recall on my '71. I think this 9 leaf spring will be getting a new set of spacers, cups and a new lease on life! Thanks

TheSaint

This looks nice Where do you get the tool to do this job?

Is it just a holder that fits in the cup and a cone to press(bolt/screw)it in place like it looks like on the pictures?

Mike67nv

The tool was made by a NCRS member that loans it for the price of postage, although I think most people include a tip when returning it. He wrote an article on it in the NCRS Corvette Restorer (Fall 2009) with his contact information. It’s a three-step process using three different swage pieces. You place the bolt through the backing disc, through the cup, install one of the swage pieces, nut and washer, then tighten it to roll over the cup edge. The different swage pieces begin to roll the cup edge over in steps and finally flatten it.