Have you ever replaced the drums? They could be out of balance. I had my drums and hubs on the front of our 300C balanced by a speed shop.
Tomorrow AM we leave for the 300 Meet with a stop on the way to visit our son and family in Walnut Creek, CA
Hi Ray -
Reading your post, I think the problem is one of three things: your tires are bad, your rims are bad, or your tires and rims are bad.
I have heard a lot about Coker Classics. Most of it bad: Excessive weights needed, premature separation, flat spots. Any of this sound familiar ?
My advice is to junk the tires and go with American Classics. Have those on two of my cars. Very happy.
From: Chrysler300@xxxxxxxxxxxxxxx [mailto:Chrysler300@xxxxxxxxxxxxxxx] On Behalf Of Ray Melton rfmelton@xxxxxxx [Chrysler300]
My recently restored 1957 Chrysler 300C convertible has a set of new-ish wide-whitewall 235/75-15 Coker Classic tires on a set of chrome wire wheels made by Motor Wheels. The wheels are at least 40 years old, but are still in excellent condition. However, due to an extended restoration, the tires are now over 6 years old, but still have the "whiskers", having accumulated only 500 miles. I had the steering aligned and the wheels/tires balanced at a very meticulous and cooperative alignment shop using the Hunter "Road Force" equipment. I was surprised that each wheel took at least 5 ounces of weights, with one requiring 8 ounces - all over the inside and outside of the rims! The Hunter equipment showed that lateral and radial runout of the wheels and tires were within specs, but the total "roadforce" was above spec on two of the wheel/tire assemblies. The shop had already tried relocating the tires on the rims, so they said that's the best they could do; the residual roadforce was because of internal inconsistencies (stiffness and thickness) within the tire carcass.
The tires seem to flat-spot pretty significantly from sitting in the garage for a couple of weeks, and even after driving 20 miles at highway speeds, there is still noticeable wheel vibration. I took the car back to the alignment/balance shop and they ran it through the full balancing routine again (not just the plain spin-balancing typical at most tire shops), and their re-run came up with almost identical numbers. (They very generously only charged half-price for the re-run!)
This is the first time I've heard of separately balancing the rims alone, and was surprised that you found that it made a significant difference; I was under the impression that the combined wheel/tire balancing process took care of any imbalance of the rims alone. What did your shop do to balance just the rims alone? It seems like they wouldn't just put knock-on rim weights on the rim because that would probably interfere with the additional weights when the tire was installed. Maybe tape-weights on the inside of the rim that would not interfere with the knock-on weights after tire installation?
Can anyone clarify what I should ask the shop to do to have the rims balanced separately? Should I have the simulated knock-off hubcaps installed, since they are actually rather heavy and are somewhat unsymmetrical due the the knock-off "ears"? Seems like I would have to keep each hubcap dedicated to a particular wheel, and indexed somehow - maybe paint dots. And even if that's technically the right thing to do, I'm not sure the wheel mounting apparatus on the balancing machine could accommodate having the hubcap installed - as I recall, the wheel is held on with a big spin-on nut with large "ears" of its own.
Ray Melton Las Cruces, New Mexico
On 5/8/2018 3:38 PM, Lindsey lindsey@xxxxxxxxxxxxxxx [Chrysler300] wrote:
Posted by: <chesnutt@xxxxxxxxxxxx>
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