A few days before Christmas my wife and I were headed up to the Bay Area to spend Christmas with my son’s family. I was in the fast lane I-5 between the 55 and 57, when all of a sudden it sounded like somebody’s tire had gone flat, and then my 2013 Outback started going wibble wobby and no one would let me pull over accross the 5 lanes of traffic to get off the road, when I finally made it to the side there was no where to get out of traffic, so I very slowly drove down an off-ramp and to my delight there was an old fashioned gas station with a garage and giant racks of tires. Unfortunately they no longer fixed or sold tires. A good local was getting told me to just drive it across the street and the guy in that building fixes tires. I told him I don’t think I should drive anymore on the rim and the tire looks pretty good, maybe I shouldn’t risk destroying it. " Nah he said, it’ll be fine man." To make a long story short the guy in the building took my wheel off and it looked like some one had shot a .223 round straight through the middle of the tread of my mud/snow tires. “Dude, that’s the cleanest hole I’ve ever seen in a tire” I’ll just plug it and you’ll be sweet. But don’t you think the rim is damaged? “Nah” Don’t you think the steel belts might be damaged “Nah” How can you tell, you didn’t even take the tire off the rim. "I have a feeling for these things, look at the tire, it looks sweet. " So I paid him $30, and took off thinking I should turn around and head for home, but my grandson had surgery scheduled the next day so we headed out with 350 miles to go. I babied the tire for quite a while and then we got more confident, and Monday we made it 450 miles home. The tire doesn’t leak, the sidewalls look good, but I drive long distances to Utah on mountain roads, and I don’t want the tire blowing out. I know if I take it in to Discount Tire where I bought it to have it checked, they’ll tell me that yes it’s damaged beyond repair, your warranty is out, and since you have all wheel drive you’ll have to buy four matching M/S tires, and we don’t have any of the inexpensive ones available. So my question is where would you take it to get it checked, any tire place that pulls it off the rim is going to give me the same story about not being allowed to put it back on the rim if it’s bad. Should I get it checked? I can’t see anything from the outside that looks bad, it’s held pressure for 800 miles of highway speeds. Can you buy and run a single new tire for an all wheel drive subaru, the tire has maybe 12 K miles on it, or will the difference in wear mess up the AWD.
If you have any doubt and considering you drive many miles, I would buy two new tires. You don’t have to replace all four but you should always replace in at least pairs (unless very low milage on the tires). Your tires are the only part of the car that has contact with the road and, thereby, are one of the most important parts of the car.
FWIW…I plugged my Subaru Tire one night over a holiday weekend when I had to leave in the morning surprisingly it held that day and until the tire wore out.
Just an opinion but I think you’re fine. All the Discount Tire folks can do is inspect the tire for visible damage or measure it on a Road Force machine to see if it’s out of spec.
But you can also just inspect your tire sidewalls thoroughly to see if your rim caused any visible damage. And if belts were damaged I expect that you’d feel a vibration and apparently you don’t.
As far as replacing one tire an online search says it’s OK if the tread depth of the new and old tires is within 4/32 inch or 2/32 for AWD vehicles like yours. More searching says your 12000 mile tires may have worn 2/32 by now so it seems like a borderline situation.
If I were you I’d inspect the tire thoroughly for damage and check pressure more often to make sure the plug doesn’t leak and if everything looks good I wouldn’t worry.
Yeow, if you are still commuting to work, think about this: the tire fails during rush hour on the infamous busy freeways.
The rim might be fine if you didn’t notice any nonsmooth rolling on the rest of your trip. It’s the tire itself I would be worried about. But I’m not in the tire industry.
Regarding the AWD question (UGH!), a Subaru dealership’s mechanics would be the ones to ask. They’ve probably been asked similar questions many other times. So then at least you would have a tire pro’s advice and a Subaru AWD mechanic’s advice. AWD mechanisms vary in design, so that’s why I say you should ask Subaru.
Yeah I’m not sure what to make about the 1/16 of an inch measurement. Just did a rough check with a micrometer and I don’t think you can reproducibly measure 1/16 of an inch difference for tread wear for the whole tire for the three good tires without a pretty sophisticated device. At first I did have some psychosomatic vibrations, but just around 68 mph, and I decided that was the road section, on smooth road I don’t really notice anything. I am amazed though, the tire went flat when I was going about 75 mph and I drove it flat maybe 1/4 of a mile.
Yup! It went flat in about as bad of fast traffic as you could want, Teslas, Beamers, Audis all zooming around me at mach 1, honking and gesturing as I was trying to pull to the shoulder. Lucky it was a back tire or I probably would have lost control.
That must have happened today. Oh, jeez, I’m glad you didn’t get hit when pulling or pulled over. 
Well, that answers your FIRST question! Now on to the next one: 2 new tires or all 4?
I have done OK with a single tire replacement just once, when a frustratingly new tire caught a nail in a bad spot from work on a neighbor’s house. Living in a city it is hard to always avoid screws etc left behind by careless contractors. All four tires were fairly newly purchased, at the same time. That went OK.
But I was well within the margins indicated in a post above.
I’m with pikabike and Sonder on this one. You drive a lot, you drive on mountain roads, you have an AWD vehicle that implies possible offroad or snowy conditions, you have a family that drives with you, see where I’m going? You drove a quarter mile on the rim alone, how could the tire not have been affected? Why would you go by the advice of a guy that says, yeah, it looks fine? I think you were lucky to get back home safely, you may not be so lucky next time. I’d be checking that rim, too, perhaps the slight wobble at 68mph is related. I think a Subaru dealer is the place that will give you the best advice and you don’t have to buy from them. BTW, did you have a good spare?
Most of the online stuff even from the tire manufacturers says “you may be fine” if you only drive a few miles on it… and they have good reason to be ultraconservative around a potential safety (and profit) item. Everyone that gets a flat tire drives on it for at least a very short distance right?
I think you have 3 solid options:
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do nothing. Or you could take your vehicle to Discount Tire and have them pop the tire off the rim so you can inspect it inside and out for any signs of damage. You’d also get a good look at the rim but I expect it’s fine since I think you would have heard it if there was direct contact between rim and road.They can also measure *road force" (layman’s term for R1H) on their Hunter machine. Road force measures the stiffness variation around the circumference of the tire. The spec is typically around 12 pounds. If belts are damaged it should affect this measurement. If the tire is within spec that suggests that you’re fine.
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check with Discount Tire and maybe Belle Tire and see if they can shave a tire for you.
I agree with you that measurement variability might make it hard for you since you’re looking for such small differences. I’m not sure if a tread depth gauge would help. Having Discount Tire take responsibility to shave it if necessary should give you peace of mind.
- take the opportunity to put top quality tires on the vehicle. My wife’s CRV shredded a tire when it was almost new when it picked up a big chunk of metal. We replaced one tire and in retrospect I wish I had taken the opportunity to upgrade since the OEM tires suck and now that it has top quality Michelins (Crossclimate2’s) it has much better traction under all conditions plus it’s quieter with an improved ride. You might read the Tire Rack reviews for your current tires to get a feel for just how good or bad they are. Our AWD CRV and 4WD 4Runner both came with tires rated “Poor” for winter (?!) and both vehicles were transformed with top quality tires.