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An interesting (at least to me) update.

Preparing to replace my 56 rear torque arm bushings, I had two Steele 473313 bushings bough via Max Merritt a couple of years ago, and ordered two more last week to go with the 4 OEM bushings that I have coming from a generous benefactor. The comparison of today's Max Merritt bushings to the ones from him a few years ago reveals:

The ones received today (1) no longer have the "Steele" name molded into them, and (2) they are of a significantly harder durometer rubber. Kanter also mentioned to me that his bushings are made to match the original durometer hardness. So maybe new urethane parts aren't required - another ten to fourteen thousand miles after installation will tell the story.

UPDATE: I think I'll try to improvise some sort of a durometer and see if I can get some numerical comparisons between the OEM, old (Steele) and new Max bushings. I'm thinking of using a drill press to provide the force with a scale on the handle and with a pointed metal cone and measuring the force required for the cone to penetrate some measurable distance into the rubber.

Just a little follow-up. I received an OEM 473313 bushing courtesy of HH56 and rigged up a primitive durometer using a scale on the arm of a drill press. The numbers represent pounds of force required to drive a blunt round pin of 0.20 inches diameter into the rubber for a distance of 0.250 inches. One variable than cannot be accounted for is whatever effect the age of the OEM bushings might have had. It would have been nice to have one of Kanter's bushings for comparison.

OEM bushing: 5.4 lbs.
Merritt new: 4.7 lbs.
Merritt old (with Steele logo): 3.5 lbs.

The repeatability of the measurement appears to be about +/- 2 or 3 tenths of a pound.

UPDATE:

Kanter bushing: 5.2 lbs.

I am now looking into having the 1956 rear torque arm bushings made from polyurethane. Will mention in future the results.

Quote:

If you still have your set up together for testing and you have a moment stop in and I will supply you with one of Kanter's bushings. Anyway it would be great to finally meet you.

Thanks
James

James, my test rig is still together; it's a non-destructive test - why not just mail me one of your bushings and I'll test and return. Check with Dan - he knows me very well and I'm sure he'd give you the go-ahead.

Mailing address in a PM to follow.

It will go out this afternoon.

Thanks
James

Having just replaced all bushes on the arms of my '56 Patrician, there's a couple of tips in this topic I wasn't aware of at the time but would have seriously considered had I known. They are using '55 bushes and inserting a piece of rubber between bushes (size not stated). Anyway the job's done now so there's nothing to worry about for now, but for how long?

By the way, in disassembling everything I noticed the lower bushes were worn much more than the uppers. I've attached a couple of pics of the RHS bushes as these were replaced by the previous owner not long before I bought the car (I've had it for about 7 years). The LHS wasn't done by him as it apparently didn't need newies, but having a hell of a job disassembling that side makes me think they surely did need doing back then. Anyway, these RHS bushes have Packard numbers moulded into them, no mention of Steele, which could mean they were NOS.

If polyurethane bushes are suitable I'd consider redoing the job some time in the near future if it meant not having to do it again for a looong time. With my limited knowledge of the compression stresses on rubber bushes, my only concern is whether polyurethane would perform the same job (ie, compression v hardness). I'm thinking they would work well on the fronts as they seem to have a mostly rotation role, even though they are compressed during assembly.

I would also be interested in finding out more about the rear stabiliser bar (watts linkage) polyurethane bushes as the rubber ones I installed a few years ago are already showing signs of wear (the outer ones - not sure about the inners).

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You can get urethane bushings for the Watts linkage. It's not a catalog item but I got mine by calling Dan Kanter. They probably were catalog items from PST, I didn't inquire but think they are just standard shock-eye grommets.

Thanks OD, that's basically what I'm using now in rubber but will check around over here to see if there's something available in polyurethane. I am interested in finding out if there's any difference in performance or is the main benefit just longer life? When I read your comments it started me thinking that polyurethane would be a much better option because it should retain shape more readily than rubber, wear longer and therefore perform better. Cheers, John

Jp,

Was it the upper or the lower bushings that were more worn? I ask this because we have seen in cases where only the lowers were done as they are easy to do as you don't have to move that axle and as you stated the previous owner only did the right side. I just wanted to double check. As for the difference in the poly verse rubber the poly is a harder compound the ride quality may be sacrifice. If you have good quality rubber bushings like the ones that O.D. tested they should last as long as original Packard ones. Also one thing to think about is if poly was used in place of rubber in the uppers and lowers could that cause more stress on the trailing arms and reinforcement plates and I know they can fracture with worn bushing. I just wonder if you take the "give out" by removing the rubber bushing and going with a harder compound could this result in other issues.

James