I left my 2008 Honda CRV set over the summer. I started driving it again this past fall. At about 60 mph, it has a vibration like the tires have a bump on them. The dealer tells me the tires have developed flat spots and they pumped the tires up to about 40 psi and said that should work out the flat spots after a couple of thousand miles. I still have the vibration. They have performed Bullseyed balance on all the tires and performed a Roadforce. test and found tires at 45, 47, 49 and 27. Do you think that tires should have flat spots that don’t go away after driving them for a few thousand miles?
The flat shops should roll out in 2K miles. Have a friend follow you at freeway speeds and from the other car take a look at each wheel. Look to see if any bouncing can be seen from the observer car. Perhaps you can isolate one or two wheels with a problem.
A wheel could be bent, a tire might be experiencing a belt separation, or their maybe dirt accumulated on the inside of one of the wheels. A tire out of round, bent wheel, etc. won’t be helped by balancing. You might want to have a 4 wheel alignment done as well.
I’m guessing those are the original tires. If you have 30,000 miles or more on the tires, they’re probably getting close to being ready for replacement. They’re not very good tires to start with, and that fact combined with the apparent flat spot problem would have me looking for better replacements (don’t get the Duellers again).
Go to www.tirerack.com and do some research to find yourself a good set of all-season tires. Get something better-ranked than the Duellers in the consumer surveys.
Tires can develop permanent flats spots in as little as a month. From the numbers yours sat much longer than a month. I think the dealer is right - and at this point you probably need to replace the tires. Those numbers are not going to ever get good enough!
I don’t want to say that no tyres develop flat spots, but flat spots are not really common with modern cars and tyres. Back in the 60’s it was a common problem, but not today. I agree with the recommendations that have been suggested. It is also possible that some tyres just don’t get along with some suspension systems. When you change tyres, I suggest you don’t choose the same make tyre.