Radial tires too tough on Stude suspension?

[bams50]

Spent some time at Carlisle looking at different street-rod-type goodies, including front clips. There were manufacturers, builders, and parts sellers.

When I think about a top-notch build of an R2 Daytona, one thing that comes to mind is the kooky monkey-motion Stude front, with the ancient king-pins, bellcrank, and convoluted power assist. Sure, they're all fine- but between the oddities of it and the cost of rebuilding one, I've toyed with the idea of a modern clip.

So I talked to a few vendors about this and what I was thinking. I was surprised to hear from two separate vendors, one well-known clip manufacturer and one experienced builder, the subject statement: That is, old suspensions were not designed for the added stresses of modern radial tires. This will cause ongoing premature wear and destruction of the rubber components. Using Delrin or the like where possible will help some (at the cost of ride) but will still not resolve this issue.

I had not thought of this; but to me the concept makes sense. We've heard reports of rebuilds showing wear and even ruined bushings in relatively short times after rebuild, even with known-quality rubber installed by experienced folks.

I have not yet rebuilt a Stude suspension, and have not relished the prospect. Add to that some reports of premature failure and the oddball nature of the design, and it has me thinking seriously about clipping my project car.

What do you think? Does the radial tire theory hold water? Why or why not? Opinions welcome, experience/knowledge desired!


Robert (Bob) Andrews- on the IoMT (Island of Misfit Toys)
Parish, central NY 13131

GOD BLESS AMERICA
Ephesians 6:10-17

[Flashback]

My uncle's 55 commander ran radials for 43,000 miles.
I have ran radials on old cars for years. I don't
believe the radials are the problem. I think wide tires
and offset wheels are the problems. I just last year
dismanteled the above mentioned 55 and the front suspension
was really in good shape. This is just one opinion, but
I think the Stude frt. suspension is a good design. Course,
if I was sellin frt clips that cost more than the car, then
I might think different. OR, if I was racin

Tex in Alabama

Makin' a little progress

[StudeRich]

It will be very difficult to find the first person who can prove or even give a logical reason why his '51 to '66 Studebaker Front suspension has failed due to Radial Tires. [:0]

A wimpy older ball joint system like GM maybe.

The only thing ever reported due to the modern tires is steering effort, usually easier, sometimes more difficult probably because of some people using excess width tires.

StudeRich

[StudeDave57]

I have one car with 200,000+ miles worth of radial tire driving on it.
I have another with 20,000+ miles of radials and Delrin up front.

BOTH of the above cars have wider wheels installed.

No abnormal issues as yet... [:0]



StudeDave '57 [8D]
Ferndale, WA

'54 Commander Regal 4dr 'Ruby'
'57 Parkview 'Betsy' (she's a 2dr wagon)
'57 Commander DeLuxe 2dr 'Baby'
'57 Champion Custom 2dr 'Jewel'
'58 Packard sedan 'Cleo'
'65 Cruiser 'Sweet Pea'

[53k]

I put Michelin tube-type radials on my '64 Wagonaire in 1967 and I have never looked back. I can't imagine kingpins being flimsy compared to ball joints. Why would big trucks still be using them? I have never seen a Studebaker alongside the road with a front wheel cocked at a wild angle.



Paul Johnson, Wild and Wonderful West Virginia. '64 Daytona Wagonaire, '64 Daytona convertible, '53 Commander Starliner, Museum R-4 engine, '62 Gravely Model L, '72 Gravely Model 430

[Dan Timberlake]

Bias ply and bias belted tires were losing ground to radial tires in the early 70s. Slight harshness of some kinds of bumps made some owners regret buying radial tires. Some shock absorbers claimed to have valving designed and developed to reduce radial tires' harshness. Pontiac and others made "radial tuned" suspension a marketing feature. http://www.texastransams.com/articles/faq.htm#Q11 .

Here are some interesting reports about using radials, mostly on Chrysler Imperials of the 60s. There are some reports of Suspension and steering wear, presumed to result from greater traction. Even a reference to a 1948 Studebaker. http://www.imperialclub.com/Repair/Wheels/radials.htm

[55s]

EVEN IF there were some suspension issues related to Studebaker suspension and premature wear, I simply don`t put on enough miles to worry about it.

Right now, I need to figure out how to use up my 5 year old, almost new tred tires in the next 2-3 years before the rubber is no good.

Maybe a few trips to California are in the works as soon as I put in some air conditioning.

[Mike Sal]

Speaking of tires, have any of you used some of the 165/80-15 tires that were mentioned a while back (discount tires.com). I just checked the site & they're priced at 52.00/each.
Mike Sal

[chey]

Iam thinking seriously about a front clip on my Hawk for the power steering and the upgrade on the brakes. The guy I talked with measured the width of the backing plates and frame rails and a metric front clip will fit nicely.

[bams50]

I wonder if there is more stress from the better traction and width of modern tires more than the radial aspect specifically. We've heard about wheels cracking and hubcaps rotating due to tire stresses; might that not translate to forces not considered when the suspension was designed? Think about how far tire tech has come over the years. Not saying tires could 'break' the Stude suspension, but I wonder about tearing the rubber parts up...

Still, I hear all the comments from those of you who have run radials long term. Conflicting experiences?

My last Lincoln convertible had a complete suspension rebuild done by a noted Lincoln expert. The bushings were all fresh, new, top quality stuff. So the originals lasted over 40 years, but the replacements started tearing apart in about 3. And those 3 were all pampered, gentle, fair-weather use. The only other difference?

Radial tires.

I don't know if the tires were the culprit, but it does make one suspicious...

Robert (Bob) Andrews- on the IoMT (Island of Misfit Toys)
Parish, central NY 13131

GOD BLESS AMERICA
Ephesians 6:10-17

[mbstude]

quote:Originally posted by bams50

I
My last Lincoln convertible had a complete suspension rebuild done by a noted Lincoln expert. The bushings were all fresh, new, top quality stuff. So the originals lasted over 40 years, but the replacements started tearing apart in about 3. And those 3 were all pampered, gentle, fair-weather use. The only other difference?

Radial tires.

I'd think that has more to do with the bushings not being the same material/quality as the originals.

We've always ran radials on all our regular driver Studes (except one). No problems. Of course, we do drive our cars.

[Gunslinger]

Back in the '70s I sold tires and that issue was brought up and you could get a different answer depending on who you asked. Allegedly the superior adhesion of a radial tires stressed any car's suspension beyond what it was accustomed to. Most car manufacturers didn't have radial tires on their mind when designing their suspensions. The same could be said of oe wheel rims. Some suspensions and rim combinations were inherently stronger than others...all had their stress limits.

My own feeling is most fears were based on the fact that radial tires were pretty much an unknown commodity to most consumers...much as fears of unleaded gas effects on valves, radial tires originally were said to only be rotated differently, etc. Such fears have gone by the wayside as time and experience have shown otherwise. Even Chrysler did not recommend radial tires on their cars built before a certain date sometime in the '70s...I guess they didn't think their torsion bar suspensions were compatible. I remember car makers were touting some cars had "radial tuned suspensions" to allay fears...really nothing more than a slightly heavier version of the same parts...if that. It may have been nothing more than advertising hype.

The only real change necessary when installing radial tires in place of bias ply tires is a slight change in alignment specs.

I believe a worn suspension is a worn suspension...and no tire of whatever design is going to make that better or worse.




Poet...Mystic...Soldier of Fortune. As always...self-absorbed, adversarial, cocky and in general a malcontent.

[sbca96]

I honestly dont think that radial tires will cause a Stude suspension
to wear out quicker, more so the roads one drives on, and how well the
replacement parts were installed. Those rubber bushings need to be
torqued with the car at RIDE height. Too many people torque them when
the car is in the air, this grabs the inner sleeve and will preload
the rubber bushing. Add to that gushy shocks, worn springs and other
issues and you have LOTS of extra stress having nothing to do with the
tire type. I ran radials on my Hawk for years with no ill effects, I
cant say much about the Avanti because it just plain doesnt get driven
anywhere near as much as I would like.

I think that improper assembly due to ignorant mechanics are a Studes
biggest enemy, I bet there are MANY Studes that have never had a proper
alignment because the shop doesnt know about the pinch bolt and the zerk
fitting that gets removed to adjust camber and caster. I was told out
right that Studes can NOT be adjusted, and have heard of shops heating
the pinch bolt goose neck and BENDING it to adjust camber and caster!

Tom

'63 Avanti, zinc plated drilled & slotted 03 Mustang Cobra 13" front disc/98 GT rear brakes, 03 Cobra 17" wheels, GM alt, 97 Z28 leather seats, soon: TKO 5-spd, Ported heads w/SST full flow valves, 'R3' 276 cam, Edelbrock AFB Carb, GM HEI distributor, 8.8mm plug wires

[PackardV8]

FWIW, I drive my Studes through the corners hard enough to scrape the chrome off the door handles and have been doing it for fifty years.

1. The wimpy front sway bar and bias ply 6.70s would slide way before much cornering force was developed.
2. Add wider tubeless radial tires on the OEM wheels and wheelcovers fly off and the wheel rim eventually cracks. The front crossmember-to-frame and the upper suspension mounting points were known weak points even back in the day.
3. Add wider, heavier wheels, wider radial tires, thicker sway bar and the forces have to go somewhere. And yes, I'm not convinced the repop bushings are as good as the OEMs.
4. I've done a bunch of front clips; Nova, Fatman and the like, all for other people. On my own cars, I keep the Stude front suspension. All new wear parts, post-'62 kingpins and shim to get the caster and camber where it should be If I change anything, it is only the power steering. Stude is no worse than Ford or Mopar of the day. They were all using the same junk.

Bottom line - your car, your money, your decision. Find someone who has a Stude with EXACTLY the modification you are considering. Drive his car. Then drive the same model Stude with all new OEM suspension. Compare the two. Ask how much the front clip cost. Double whatever he admitted to.

thnx, jack vines

PackardV8

[nels]

I think you are right Tom, if the Stude suspension is greased regularly. it will hold up great. The advantage of ball joints is that they can sustain more wear without noticing it in drivability. The reason being that the spread between the upper and lower ball joint is maybe 10 inchs (?) and the spread between the upper and lower bushing in the kingpin is maybe 5 inchs (?). Ten thousanths wear in a ball joint may not be noticable but the same wear in a kingpin would be noticed in the camber and caster slop while driving. Ball joints were successful mostly because people are lazy and don't grease their front ends therefore they wear fast but the wear is not noticed as soon. I think the kingpins are just fine as long as there is grease in them.
As Tom pointed out with the pivot bushings, they are supposed to be tightened up when the suspension is loaded. I doubt many shops realize that or even care.