Rear leaf spring bushings and shackles?

[78CobraII]

I just pulled my rear suspension so that I can complete the restoration on that area.

The bushings are pretty spongy, and the bolts passing through them are pretty rusty, so I want to replace them.

I checked the polyurethane websites I knew of (Prothane, Energy Suspension) and drew a blank for new poly bushings...does anyone have a source?

I ordered new spring shackles from JCWhitney, and they come with new rubber bushings, so I'll let everyone know how those do.

I still need to get new "U" bolts as some of mine are pretty rough. I need longer ones anyway since I eventually plan on trying lowering blocks.

 

[Cool Wheels]

Mustangs Unlimited doesn't have em either. I seem to remember looking at some a while back though (???) They do have the regular shackles for 14.95 ea

Do let us know how the ride feels in a "descriptive feel" sense compared to poly parts if you've felt the difference.

Guess it sounds like we have no choice anyway but I actually like my rubber bushings. Softens up the bumps on the road. Haven't tried poly yet.

PS: The nice thing I just realized about M-Unlim. is the II parts are the 1st ones listed when you browse. Makes shopping convenient for us. Too bad they didn't carry more.

 

[Blue Thunder]

PST (performance suspension technology) in NJ had the poly bushings, I think.

 

[1badII]

Racer Walsh has high durometer rubber bushings and aluminum bushings. www.espo.com has polyurethane shackle-to-frame bushings.

 

[78CobraII]

PST was the other suspension company that I was looking for. I just checked their website and they don't list poly leaf spring bushings for the Mustang II. You would think that the dimensions of the MII parts would not differ much from the earlier Mustangs...

The ESPO site looks much more promising. I'll order the poly leaf spring bushings from them and let everyone know how it goes.

 

[cobra_2_76]

Measure the outside diameter of your old bushings and ask for a set with the same diameter. I think I had to buy two sets and cut the length down to fit the II springs, but don't remember the model. I pressed them in with a 6 inch vice and silicon spray.

Dave

 

[78CobraII]

The new rear shackles came in from JCW. They look pretty good except for one thing...there is about an additional 3/4" between the hanger bushing centerline and the leaf spring busing centerline compared to the stock MII part. So I would end up with (nearly) an additional 3/4" in height at the rear of the car.

The rubber bushings included with the shackles seem to be a little bit harder than the stock MII parts also.

Other than that, they seem to be an exact copy.

I would consider re-drilling the holes for the shackles, but the shafts seem to be pressed into one of the side plates. My lowering blocks seem to be a bit thicker than I had planned, so this little extra height might actually be helpful.

Temporarily I'll just have a set of stock shackles sandblasted and repaint them.

 

[78CobraII]

I've had 2 batches of parts sandblasted so far and am hoping to get them painted this weekend. My wallet is $55 lighter, and I figure that I have at least $200 more to go, but at least this is reducing my cleaning and prep time to almost nothing. Next week I'll carry him leaf springs and bumper re-inforcement beams.

I'm going to re-assemble the rear suspension with stock rubber parts for a while as my leaf spring bushings and spring isolators cleaned up pretty nicely. They are a little ragged around the edges where they are exposed to the air, but the insides look fine after a vigorous cleaning. They actually had rust embedded into the surface of the rubber, so I thought that they were disentegrating, but soaking them in diluted muriatic acid for a couple of days allowed me to scrub and scrape the rust away. Now the rubber parts look pretty good.

My sway bar bushings will all be poly from the start, but I'll leave the leaf spring bushings, etc. in rubber until I'm ready to rebuild the front suspension. Then I'll replace everything with poly.

I think that between the V8 sway bars (1" front, 3/4" rear) and the poly bushings, my little 2.3L powered Ghia should handle pretty well.

 

[78CobraII]

Its 4 months later and I still haven't carried the leaf springs and bumper reinforcements to the sandblaster!

I did finally try to get the bushings OUT of the leaf spring ends though...

...one end came out easy (the rear end), but the front end has a metal tube through the bushings and another metal tube wrapping the bushing. The outer tube was swaged outwards in 4 places on each end, but even after removing the swages and soaking everything in penetrant, the bushings would not budge.

Are the forward leaf spring bushings usually pressed in/out?

Thanks.

 

[IIxs]

It may sound primitive but if you burn out the rubber part of the bushing, you can use a hacksaw blade and cut through the steel sleeve and it will come right out.

BTW the shackles on the early (75-76) cars are about 5/8" longer than the later cars (77-78) and they probably modeled your new shackles after the early ones.

 

[cobra_2_76]

Yes they are pressed in. Burning works too, but is real messy and smokey.

Take you pick.

Dave

 

[Blue Thunder]

Fire is good!
Torches are good!
Burning spring shackle rubber is good!