i have a 1951 pontiac convertible and am having trouble keeping one hubcap on after driving for a couple of years with no problems…any thoughts?
Thoughts , yes. If these are original hubcaps I would take them all off and only put them on for car shows and find something else to use when just driving around . Assuming it is the same wheel all the time I would say that wheel is out of round.
The spring function – however it is done on a 51 Pontiac – that holds them on the wheel must be getting weaker w/use. From the number of hubcaps laying in the gutter I see on my daily walk-a-bouts, this problem still hasn’t been solved. If I had that problem I’d compare both hubcaps by visual inspection, including roundness, and how springy the attachment method seems. Are you able to past a photo of the rear of the hubcap, and the front of the wheel (without hubcap)? That might bring up some ideas here.
Switch hub caps with another wheel and see if that helps. If not, you will know whether it I should the wheel or the hub cap.
Do you have hubcaps or full wheel covers? If you have hubcaps, there are spring clips on the wheels. As I remember from my 1955 Pontiac, these clips were rivited to the wheel. I had that problem and at that time could purchase new clips. As I remember, I drilled out the rivets and used a bolt and nut to attach the new clips
If you have wheel covers, there are clips around the edges of the cover. You may be able to bend them out slightly for s better grip on the wheel.
My guess is that since your Pontiac is a convertible, you have the full wheel covers. The convertible was only available in the higher trim line which normally included full wheel covers.
Hot rod magazines sometimes have advertisements for companies that offer replica hubcaps for classic vehicles. Perhaps there you could get a replacement with a good retainer spring. The spring on yours may be just losing its spring.
It could be the wheel, not the hubcap. Happened to me.
Swap hubcaps, see what happens.