Front-end shimmy

[1935Packard]

I had the front leaf springs replaced and a new front driver's side tire mounted on my '35 this fall, and I noticed recently that I'm getting some front-end shimmy when I'm going around 40 mph. Any thoughts as to where I should look first to diagnose the cause? The car is mostly stored away for the winter, but at least I can think of my spring projects in the meantime.....

Hope all are well,

1935Packard

Edited October 7, 2016 by 1935Packard (see edit history)

[Owen_Dyneto]

Assuming wheels and tires and in balance, wheel bearings are properly adjusted and the king pins and spring shackles are all tight, first thing to do is to have the front end alignment checked. King pin angle is set by tapered shims between the spring and the axle and these may have either been forgotten or no longer are correct for the new springs.

[34PackardRoadsta]

Also have the tires checked for out of round. I had shimmy problems after replacing my 34 tires. No amount of balancing helped, because the tires were uneven.

[Tom M]

I had the front leaf springs replaced and a new front driver's side tire mounted on my '35 this fall, and I noticed recently that I'm getting some front-end shimmy when I'm going around 40 mph. Any thoughts as to where I should look first to diagnose the cause? The car is mostly stored away for the winter, but at least I can think of my spring projects in the meantime.....

Hope all are well,

1935Packard

35Packard,

Same with my car. I installed brand new Firestone's. I took the tires to a local truck tire place they put it on the tire machine and same situation as 34PackardRoadsta stated it would take a large amount of weights to balance them.

I did not have this problem with the old tires and before I refinished the wooden spokes and rims?

So where do we go with the tires if they are that much out of round?

Thanks for you feedback.

[Marty Roth]

Some truck-tire places still have the ability to "TRUE" an out-of-round tire.

You could also check with places which deal with racing tires.

[Tom M]

Marty,

Can all my NEW tires be that much out of round?

Could having the rims and spokes sand blasted caused them to become out of round?

[34PackardRoadsta]

Tom,

Mine were pretty bad. I think they sit bound for shipping for a long time. I highly doubt that sandblasting would have generated enough heat to warp your rims. Are they spoke rims? If so, it is possible that some of the spokes loosened and the rim warped.

Cheers,

Tom

[Tom M]

Hi Tom,

I have the wooden spoke wheels

After paint, staining and Gloss Clear Spar Varnish

As mounted on car

So it could be I have some loose spokes?

Thanks for feedback all

[ply33]

Can all my NEW tires be that much out of round?

Last two go a rounds with new tires for my old car had tires woefully out of balance. Might have been out of round too but I never measured that. I do know that all my rims checked as true with a dial indicator both radially and side to side. Also the rims by themselves showed to be in balance. But once the tires went on it took an awful large set of weights on each wheel to bring them into balance.

The experience has led me to be skeptical of current quality by manufacturers of small run specialty tires.

Turns out that both sets of tires, even though different brands and purchased years apart, had tire codes that indicated they came from the same manufacturing plant in the US (these were not imported tires). Your luck might be better as I read in the business press about a year ago that the actual manufacturer had gone out of business and the plant shuttered. Don't know who the vendors we buy from are actually contracting to for manufacture nowadays, maybe they have better suppliers. Or maybe not.

[34PackardRoadsta]

Tom,

I am not familiar with how wood artillery wheels are put together. Can the wood spokes warp? Did you check the rims for trueness? As ply33 stated, it is pretty easy to do with a dial caliper. Or bring them to a tire place and have them check.

Good luck finding a solution.

Cheers,

Tom

[Tom M]

Tom,

I did not check the rims for trueness before I mounted the new tires since they did not have any wobble before installing the new tires.

Maybe they are out now I am not sure. If I need to check the rims for trueness does this mean I will need to dismount the tires?

As you probably know it is not and easy task to dismount them and we would run the risk of scratching up the paint etc.

Maybe I will just drive under 40 and live with it or is that not a good idear?

[ply33]

Jack up the wheel, put a block or something to firmly hold your dial indicator to the garage floor and set the indicator against the rim as near as you can by the tire. Then rotate the wheel and look for movement on the indicator. You will want to do it twice on each wheel, once with the indicator set to measure side to side motion and once on the surface near the spokes to measure radial run out. No need to dismount the tires or remove the wheels from the car.

If you don't have a dial indicator, set up a rod so it just touches the rim at the nearest point of the wheel's revolution and then use a feeler gauge to measure the distance when the wheel is farthest from the pointer.

[Tom M]

Ply33,

Thanks for the how-to. I do not have a dial indicator but I am sure I can check with some friends who may have one.

It is a bit cold out in the garage plus we have all the summer outdoor thingies in the garage that are in my way

This procedure may have to wait.

Am thinking out loud here. But what if I take the side-mount tires that have the old tires mounted to them and give them a run

on the front. This may tell me if its the new tires?

Edited February 1, 2013 by Packin31 (see edit history)

[34PackardRoadsta]

Tom,

I would say to follow Ply33's instructions. At the same time you check for rim trueness, you can check the tires themselves (same procedure, just on the tire), though a dial indicator for the tires is overkill. Just use a stick and see how much the tires vary as they rotate. Place the stick horizontal relative to the tread, very close to the tread, and give the wheel a spin. If you see large variation in the gap between stick and tread, the tire needs to be shaved.

Cheers,

Tom

[Tom M]

Update over the winter the whites on the tires turned yellow. I wrote an email to the place I purchased the tires had replied back asking me few questions.

Instead emailing I gave him a call back today. He stated that it a manufacturers defect on how they installed the white wall.

So at no cost to me with shipping they will be sending me 4 new tires. All I need to do is send him back the other ones.

Not sure if it correct for me to say what company it is but it is https://www.universaltire.com/

[Tom M]

What quick service I have received from Universal Tire. When we got home from work on Friday four tires were sitting on our front stoop.

My twin and younger brother came over on Saturday and help me dismount the other tires. My nicely paint rims got a few chips here and there I knew that was going to happen because them snap rings are not the easiest to get off and on.

A little sanding and touch up will be needed.

Before mounting the new tires we took the rims over to a tire/truck repair shop. They put them on a machine and four out of the six had noticeable out of roundness to them. The two that did not we marked to use for the fronts. The worst ones we used for the side mounts.

I still will need to take tires back to shop and see how they balance out with the new tires.

Can these rims with wooden spokes be straighten?

If new ones are in order in the future I think them chrome wire spoke rims would look good on the car.

Is anyone making the chromed spoke ones for the '31?

Thanks all for you input.

[1935Packard]

With apologies for bring up an old thread, I finally had that shimmying problem checked out.  As a few folks suggested might be the case, the problem was just the tires: The front tires I bought from Coker were both badly out of round.   A new set of tires solved the problem.  What a difference, both in terms of solving the shimmying and the overall feel of the car.  Of course, I laugh at myself that it took me three years and around 1,500 miles to get around to addressing this, but that's life.

[tigersdad]

Glad you brought this subject back up.  It's never too late to help other people out!  Where were the new tires purchased from?  Make/Manufacturer?  Thanks so much as this will help me for future needs.

 

Jay

Novato, CA

[1935Packard]

21 hours ago, tigersdad said:

Glad you brought this subject back up.  It's never too late to help other people out!  Where were the new tires purchased from?  Make/Manufacturer?  Thanks so much as this will help me for future needs.

 

Jay

Novato, CA

 Jay, I bought both the old tires and the new tires from Coker.  The old tires were the B.F. Goodrich design, and the new ones are the Firestone design,  both with the wide white walls and sized for the 12s at 7.50X17.

 

in terms of manufacturer, I'm not actually sure who makes them.  (I am guessing that they are licensed to have the old Firestone design, not actually made by Firestone.) When I called around to see what tires are available, it turned out that both Coker and Universal Tire had the wide white walls with the Firestone design.  At first I assumed that both Coker and Universal had licenses to make them, but when I inquired it turned out that they actually get the tires from the same source;  it's the same tire, just sold by two different companies.  

 

I hope that helps.

Edited October 9, 2016 by 1935Packard (see edit history)

[Matt Harwood]

It's all Coker. They make all old car bias-ply whitewalls. Coker owns Universal, Lucas, and every other old car tire supplier. They keep the names to make it look like there are multiple manufacturers/suppliers, but Coker is the only one. It's why quality has gone down while prices have gone up. The tires are made in PA or, more likely, Vietnam. Coker bought the molds and pays a licensing fee to the various manufacturers whose names are on the sidewalls, but Firestone and BFG have no connection to the tires we buy. I suspect they use the same carcass inside and just put it in different molds to give it a different look--I've had both the Firestones and BFGs show defects and have issues in identical ways, so I'm guessing the manufacturing process is the same.

 

Keep an eye on your new whitewalls--hopefully they don't start to turn gray/brown. Every Firestone I've bought from them has, but I've only bought them in 18 and 20 inch sizes.

[1935Packard]

Thanks, Matt, that's good to know.  I had wondered why the prices for that tire were identical at the different places.  And when I spoke to the Coker employee who has worked there for a while about the differences between the Firestones and BFGs, he said they were primarily cosmetic differences -- which is consistent with your view that they're basically the sam tire. 

 

And I'll watch for the discoloration, too.

Edited October 9, 2016 by 1935Packard (see edit history)

[Guest shinyhubcap]

I don't think you are being fair picking on Coker for the phenomena of "out-of-round" tires.   This problem was quite common clear up to the end of mass-produced bias tires.   Just about any tire shop of any competence had a "tire-knife"  (that's what we called em in the old days)  .  Tire installers correctly recognized if a tire was more than, oh..say....3/32's out of round - you could balance it till you turned blue, but the customer would still complain about vibrations and/or a rough ride.

The introduction of modern radials,  and the improvements in tire mfg. technology, have pretty much eliminated the need for "tire knives" or "tire truing" machines - yes - some truck tire shops still have them - now go find someone who knows how to use the things !

 

As for pre-independent front suspension Packards - yes -everything you guys have discussed is true.   Anyone figured out what that "four-spring" left rear device is on the back of the left front spring ?  Packard's  "some-times successful" attempt to eliminate the shimmy or "harmonic flutter" that you can generate if you hit the right combination of road surface between oh, say...32 to 45 mph.

 

Suggestion...when all else fails to eliminate the "shimmy nuisance"...try fiddling with the toe-in  / toe-out.   You may have to go a trace beyond factory settings, even incur a bit of extra tire wear on tire  ( the inside or out-side of the tire's tread  - depending on what you have to do to eliminate shimmy)  but that will do it !

[Matt Harwood]

I spent more than $13,000 on tires this year with a variety of sources. I have a 40% failure rate with Coker tires for cars in my shop (with "failure" ranging from whitewalls that turn brown in a matter of days to impossible to balance to out-of-round to broken belts to valve stem separation on inner tubes). On my personal cars, I have a 100% failure rate with Coker products.

 

I feel wholly justified in saying that their quality is crapola.

[tigersdad]

Matt -

 

This is what I had read earlier on the Forum under a couple of different headings and all had said the same thing that you have said!  They refused to use the name, but said it was the guy in TN with the big mustache and the name that ended in the name of a soft drink with an R on the end. So, yes, it appears that everyone else on this site is in agreement with what you've said!

 

Jay