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Tire problem or worse?

My 2006 Hyundai Elantra’s driver side front tire unexpectedly blew out yesterday on the highway. I very slowly drove it to safety - < 1mile - and proceeded to change the tire. After driving on the spare for about 50 miles, I get out of the car to check it. It was HOT!! I check the rim, and that center - cylinder thing, and they are hot as well! Curiously I check the passenger side front tire. That tire is barely warm, but the rim does also have some heat to it.

Is there potentially something wrong other than a blow out, and can these two instances possibly be related? Or am I making things up, and just need to put a new tire and carry on with my day?

The temporary spare tire (assuming you have the small hard compact version for a spare) will run hot. 50 miles is a lot of miles for that spare and if you were driving at highway speeds I’d expect it to be very hot. Those temp spares are supposed to be driven at 50 mph MAX.

Your old tire is likely trash, due to sidewall damage. When you get a permanent tire replacement on the car tell them about the blow out and have them inspect the wheel bearing and the brake to make sure there is no underlying problem. I suspect all is well.

The blown tire would also be very hot due to the huge friction of rolling without any air in it for even a short distance. If the tire was under-inflated before it blew (very common, since a tire with 20 lbs pressure can “look” OK but really be seriously under-inflated) then it likely was running very hot which caused the blow out.

So the metal rim was hot?
That could be a dragging brake.
It’s possible the rim of the regular tire got so hot it melted the tire where it meets the rim.

Appreciate such quick responses. I have the car up on a jack now. New tire on the rim, which I moved to the back. With the driver side front off the ground, I am attempting to turn the rotor (not sure if this is relevant). It is difficult to turn.

Jack up the front driver’s side and try spinning the wheel by hand. If it isn’t turning freely, don;t drive the vehicle until it’s looked into. Have ot towed to your favorite shop.

While a low tire will generate heat, your emphasis on the word HOT suggests to me that you may have a dragging brake, and that heat can cause catastrophic failure of a tire. It can also cause other problems such as damage to the braking components, including boiling the fluid. It’s imperative that you find out if you have a dragging brake and get it corrected of you do.

Post back.

I am going to find a way to get the car to my brother-in-laws house. We are starting with the calipers. There is a sensor on the (master cylinder?), so he seems to think if there was something wrong with that, it would show up on my dash cluster.

One more development - he drove the car around my development for < 10 minutes, and both front rotors were hot. Would two calipers fail @ 82,000 miles?

He may have been referring to the ABS sensing ring. There’s a ring and sensor at each wheel to sense how fast the wheel is turning. He’s correct, if something was wrong with that you’d get an ABS light on the dash.

Is is entirely possible for two front rotors to be dragging. However, it’s much more common for one caliper to be sticking intermittantly. That would manifest itself as the large temperature difference you first felt and perhaps the lack of a difference when your brother in law tested the car.

Was the spare you installed properly inflated? If it was low, (most spares are) it would get warm…

If the caliper is stuck, the wheel will be difficult to rotate when jacked off the ground. Disc brakes always have a LITTLE drag under the conditions set above…

Isn’t an Elantra a front wheel drive? You would have to have both front wheels off the ground and the trans in neutral for the rotate by hand test.

Nope. You only have to have the trans in neutral and the parking brakes on (or the wheels chocked).

FWD vehicles contain differentials just like RWD vehicles, except they’re in the same housing as the tranny (or bolted to it). What happens is that with the opposing wheel kept stable, the difference between the wheel you’re spinning and the stable wheel is taken up by the tranny output shaft, the shaft’s rotational speed dependant upon the ratio between the tailshaft and the axle. The major difference is that there is no "ring & pinion"as we usually think of it, because the axle axis is parallel to the tranny output shaft. Helically cut gears are used instead.

It’s exactly like a RWD. Jack up one rear wheel, put it in neutral, hold the opposing wheel in place, and when you spin the elevated wheel the opposing wheel stays stable and the driveshaft turns, its speed dependant upon the ring & pinion ratios.

Oooops, thanks for the clarification.