A while back, I bought some aftermarket rims for my '15 Golf to replace the sad 15" 195-section tires that came stock, and got 17 Sparco Pro Corsa rims with BF Goodrich gforce comp-2 all seasons.
It drove great for a few weeks, (beautifully, even). Then I hit the mother of all potholes. My stomach sank the moment I ran over this product of poor infrastructure management. Little did I know I would be cursing this moment for months to come.
The next day was when the vibration started. At this point, it started at 50 mph or so, and just got worse on the highway. I had to get 2 new rims on the right side, and the people at AAA said it was fine.
It wasn’t fine. Really, it wasn’t any better. So I took it back, and advised that I replace the two tires, because it was highly likely they had slipped belts from the impact. A couple more hundred dollars later, it was… a little better. But it wasn’t back to normal. By this point I was done with AAA, and went to the dealer. They noticed that one of the spacers was installed crooked. Great. They fixed that, and didn’t notice anything wrong until the next time I went on the interstate, when I noticed that, indeed, it still was vibrating. This time, however, it was just above 65 mph.
This is where I should describe the vibration in greater detail. From 0 to 65, nothing is wrong. But as soon as I hit 65, the steering wheel shimmys and the car whole car lightly shakes. It goes in and out, like it is being occasionally canceled out, and is not throtttle, braking, or turning sensitive.
Back to the dealer it was, and of course, they could not find the root of my frustration. They did put the stock wheels on, and the vibration stopped. With the aftermarket ones, it still did vibrate, even with a rotation, balancing, allignment, et cetera.
So, the question is: what the heck is going on? How can this be A) diagnosed and B) fixed without getting new wheels/tires or renting a chassis dyno?
As someone who both loves driving and has a pet peeve for this sort of thing, any advice you could give would be most appreciated.
You answered your own question. You say the problem was solved when the stock wheels and tires were reinstalled. So you can either reinstall the stock tires, or figure out which of the existing tire/wheel combination, is the culprit. Good luck.
P.S. Don’t blame just the pot hole. Some of the blame also goes to lower profile tires and the driver not slowing or avoiding it ( I know this is not always possible ). But those are my 2 cents worth anyways.
Bent wheel, pure and simple. Big pothole, low profile tires and Voila! Bent rim.
I am not surprised the dealer didn’t identify the bent wheel but Tire Busters are usually the lowest form of service tech in the building. There are also covers over the wheel on the balance machine so he can’t see the wheel wobble.
You might try getting them road force balanced . I know someone that has a subaru with 3 out of 4 bent aftermarket wheels . The car shook & carried on until he had the tires road force balanced & now it’s smooth as silk . I was amazed .
First step, rotate the tires and wheels front to back. The vibration ought to move from the steering wheel to the seat back. If it doesn’t, then it’s not the tires and wheels.
While you may think you’ve traced it down to the tires and wheels, it just might be the mounting. If the test reveals the problem doesn’t move, then it might be the way the wheels sit on the hub.
It’s been mentioned that the wheels have centering ring (hub rings) - but are they the correct ones? Are they really centering the wheel on the hubs?
Also, to help diagnose this, you need to find someone with a Hunter GSP9700 - and knows how to use it.
Yup, I’ve had those plastic hub-centric spacers on a couple sets of winter wheels. They don’t generally fit as tightly as OEM wheels.
I have a set of wheels for my Mustang that suffer a bit from this. The pilot hole is a bit bigger than the factory pilot. This takes a bit more care to mount them. You can’t just mount and hammer one lug home with an impact and work your way around the pattern. You must snug them all down is at least 3 steps to insure they are concentric. If you don’t a vibration occurs not unlike what the OP describes. A bit of a PIA but I like the wheels…
Another victim of the big rim fad.
I went from 16" steel to 15" alloy on my Toyota Matrix; 195 width.
They are smoother, quieter, sturdier, lighter and less expensive.
They handle just fine with any sane maneuvers one might make on public roads.