My basic question: How do I determine if a stock rim is defective (out-of-round, whatever)?


Full story:

I have a 2018 SR5 4WD that I bought new in November '18.

I'm a fan of the BFG TA's after running them on my two Xterras. (I also had BFG MT's on my Wrangler Rubicon, never had trouble with those.) So I had a set of KO2's (LT) installed the day after I bought my SR5.

They were purchased and installed at one of several local Discount Tire locations. They are the OEM size, 265/70 R17, and installed on the stock rims.

Everything seemed okay at first, though I did at times feel a little vibration. I wasn't sure of the source though I felt it mostly right in the driver's seat...

A few months later I had the first rotation/balance. Immediately, I had a noticeable steering wheel shimmy at highway speeds.

Thus followed several attempts by different DT shops to sort this out. Including rebalancing, roadforcing, and force matching. The shimmy persisted.

At one point while all this was going on, I numbered the rims so I could keep an eye on things...

Eventually I ended up back at the DT where I bought the tires. They spent a few hours on the job, with me in the shop watching. Eventually they determined that one of the tires was out-of-round (OOR). But also stated they suspected the rim it was on is also OOR.

They replaced the tire under the certificate, but I didn't do anything right away about the wheel. It was the rim I had written #4 on. It ended up on the right rear.

Everything was okay for awhile. I had another rotation, and this brought rim #4 up to the left front. No problems, no return visits. The next rotation sent rim #4 to the left rear. No problems I can recall, no return visits.

Then it was rotation time again. #4 ended up on the left front. I left the DT shop and got on a road with a 55 mph speed limit. The steering wheel shimmy was so bad, it was frightening.

I immediately went back and this led to another saga of balancing, roadforcing, and force matching at two DT shops. The shimmy lessened, but persisted.

I took it to a Toyota dealer and explained what had been going on. All they did was rebalance and roadforce all four wheels. Then, without telling me, moved the wheels around, placing the #4 troublemaker in the back. I had them put the wheels back where they had been. The steering wheel shimmy may have improved slightly, but was still there.

I've returned to the local DT. They dismounted the tire from the #4 rim, and spun the naked rim. I looked at it from the side while it was spinning. And it sure looked to me as if the rim edge was going up and down slightly, suggesting to me the wheel is OOR. But they told me that's not a valid way to evaluate it, that the machine would tell them if it was OOR.

They put it back together, and balanced/roadforced it while I watched. The balance was fine. The roadforce reading was 17, and the machine suggested it could get down to 16 if they force matched the tire/rim. I told them to just leave it.

Thoughts? I strongly suspect there's a problem with the rim. But how can that be verified? Other than by replacing it with a new rim?

If I were going to replace the rim, I would probably do it when I buy new tires. These now have nearly 32K on them, and I typically replace my off-road tires early.

Also...perhaps it is time to move on from BFG to something else?

If you took the time to read all this, thank you!