Spring Shackles

[Admiral]

What's the consensus on replacement spring shackles? I'm running a set of nice NOS units on my 1936 sedan, the only problem is, they creak and groan like an old man climbing a flight of stairs. I've tried tightening and loosening the crossbars and attempted to get some penetrating lubricant into the rubber, but nothing has made any difference whatsoever.

I hear there are some newer replacement-type shackles that might be better, but I'm not sure what would work best. I hear urethane bushings squeak just as bad or worse. These nylon ones from Speedway seem highly rated, but I'm not sure what's best.

https://www.speedwaymotors.com/Transverse-Front-Rear-Leaf-Spring-Shackle-Sets-w-Nylon-Bushings,2083.html

 

[bbrocksr]

What's the consensus on replacement spring shackles? I'm running a set of nice NOS units on my 1936 sedan, the only problem is, they creak and groan like an old man climbing a flight of stairs. I've tried tightening and loosening the crossbars and attempted to get some penetrating lubricant into the rubber, but nothing has made any difference whatsoever.

I hear there are some newer replacement-type shackles that might be better, but I'm not sure what would work best. I hear urethane bushings squeak just as bad or worse. These nylon ones from Speedway seem highly rated, but I'm not sure what's best.

https://www.speedwaymotors.com/Transverse-Front-Rear-Leaf-Spring-Shackle-Sets-w-Nylon-Bushings,2083.html

I used the Speedway shackles with urethane bushings and they didn't last very long. I replaced the bushings with oilite bronze bushings.
There is a lot of horizontal pressure on those bushings as well as the weight of the car.

Bill

 

[Lawson Cox]

Stick with the NOS ones. I installed the nylon ones and they have worn out in less than 2000 miles. I am beginning to think about replacing them with oilite bushings. What say y'all about that?

 

[JSeery]

There is a difference in how they work. Original Ford shackles should not allow the bolts to turn freely, they provide resistance that dampens the spring movement. More modern replacements do not.

 

[Pete]

I made my own from moly filled Delrin. I have been using this stuff since the late 50's.
You have to grease them once in awhile.
Everything should be loose and free for best chassis setup and ride.
You want MINIMAL damping in the spring itself. That is the shock absorber job.

 

[ford38v8]

I have to agree with Pete, delryn is better than nylon, and should last 100,000 miles as compared to only 50,000 miles for nylon. My Speedway nylon shackles have only about 20,000 miles on them, so I can’t be sure if they will last another 30,000 miles.

 

[DavidG]

If your new shackle studs are filled with rubber, they are not NOS, but rather NORS as Ford shifted to asbestos filled studs starting with the '33 models.

 

[Admiral]

I used the Speedway shackles with urethane bushings and they didn't last very long. I replaced the bushings with oilite bronze bushings.
There is a lot of horizontal pressure on those bushings as well as the weight of the car.

Good to know about the Speedway ones...

Bill

I made my own from moly filled Delrin. I have been using this stuff since the late 50's.
You have to grease them once in awhile.
Everything should be loose and free for best chassis setup and ride.
You want MINIMAL damping in the spring itself. That is the shock absorber job.

Delrin would be great, but man is it expensive! Have you ever tried bronze bushings?

 

[Pete]

Delrin would be great, but man is it expensive! Have you ever tried bronze bushings?

Not for that use because they won't last as long as moly-Delrin.
The set in my vintage circle track race car has 10 seasons on them and still good.

 

[fordor41]

I used moly filled Nylon bushing in my '41. installed them in about '95 and were still in the car, without any noticeable wear, when we sold it in about '17.

 

[Tinker]

It is a lot easier to use new style nylon/poly/moly bushings over the original style. If you have a points car the original style is needed. otherwise it's not really anything anyone will see. I have them on my 38, but my exhaust is a little loud (not too loud, but louder then I would like, sooo maybe too loud ) and I do not hear any squeaking.

 

[Admiral]

Not for that use because they won't last as long as moly-Delrin.
The set in my vintage circle track race car has 10 seasons on them and still good.

Great to know. I went ahead and ordered some Delrin rod from McMaster-Carr, which had it for a good price. I'm thinking of making these new shackles with grease fittings for easier maintenance. Any thoughts on this, Pete?

It is a lot easier to use new style nylon/poly/moly bushings over the original style. If you have a points car the original style is needed. otherwise it's not really anything anyone will see. I have them on my 38, but my exhaust is a little loud (not too loud, but louder then I would like, sooo maybe too loud ) and I do not hear any squeaking.

My '36 couldn't be any farther from a points car... well, it could, if it had a 350 Chevy and an automatic transmission... I'm no stickler for authenticity. I like stuff to be durable and serviceable.

 

[Pete]

Great to know. I went ahead and ordered some Delrin rod from McMaster-Carr, which had it for a good price. I'm thinking of making these new shackles with grease fittings for easier maintenance. Any thoughts on this, Pete?

Yes, they need grease.
Several ways to route the grease in. I prefer going in the side rather than drilling the shaft which weakens it. Both the inside and outside of the bushing need grease. I run .002 clearance on both.

 

[JM 35 Sedan]

Admiral, some of that groaning and squeaking you hear could be coming from the spring leaves lacking lubrication. I found that to be causing the problem on my '35 fordor sedan. When I took the spring pack apart, I could see the steel to steel rubbing marks and fretting corrosion around the tips of each leaf. After cleaning and smoothing those areas, and applying spring lube, most all of those noises disappeared.