Flat spot or tire balancing?
 

My Expy sat for 2 years and when I recently put it back on the road, I made sure to have my tires balance. At 1st, it felt like I had flat spots in my tires, but now that I've got a thousand miles or so on it, I feel like it's just out of balance now.

I've got a bad vibration from 40-50mph then it smooths back out until I get to about 75mph and there's a vibration again, but only slight at the 75mph+ speeds. Also, it runs fine below 40mph.

So what do you think it is? Can it be that my tires just need to be rebalanced again, since my flat spots are now gone, or is what I'm feeling a permanent flat spot and I should just bite the bullet and get new tires? I just hate the idea of getting new tires because the tires I have on there only have about 10K miles on them and look new!

Thanks!

I would find a shop that offers road force balancing. This will tell you for sure if it is a balance issue or you are feeling flat spots. Usually flat spots will go away after a short drive but 2 years is longer than I have ever let something sit.

If you had them balanced when you first took it out of mothballs, the tires have surely changed now that they are getting used and have probably changed a bit. I'd go the rebalance route. The other thing to consider is the age of the tires, not the mileage. Tires generally have a 5-7 year life from the date of manufacture (not the date of purchase - depending on where you got them, this date may be considerably different). You should check the date code on the sidewall just to make sure you aren't spending good money on a set that is due to be replaced anyway.

If you have a flat spot or if the belt(s) have slipped you should be able to feel it by running your hands around the tread.

Thanks folks. Tires feel fine and look great! I think I might try a road force balance. I here those Hunter road force balancing machines can't balance a tire with a flat spot because the balance a tire under load. So I figure, if they can balance the tires, I'm good. If not, I guess I'll be looking for some new tires.

I would say re balance because when it vidrates at certain speeds that is the main culprit. with vibration at two different speeds seems to be two different tires are unbalanced. If that does not work the obviously bite the bullet.

I agree with "Big Greenie", the most accurate way to get a tire balanced and checked is to have a tire machine that will put a load on the tire when it is checking/balancing it. That would give you the best results.

I had a truck with heavy duty 10 ply tires that I let sit for about the same time as yours, and when I started driving it again I found that the belts in the tires had settled and I wound up having to replace them. One of them actually threw a tread off and tore up my truck, so check them out good.