[rich8566]

Ok, so whenever I check iDrive tire pressure and temps, I notice that my left front (drivers side) tire is significantly hotter than the right front tire. I'm talking 6 degrees warmer than the other tire. The rear tires are always nearly the exact same temperature. What gives and is there something wrong here?

[Troppo]

1. Sensor fault?
2. Brake dragging ever so slightly?
3. Wheel bearing?
4. Some kind of tyre fault?

[chattanooga240]

The drivers side engine bay is hotter than the passenger side nearest the wheel well, this could definitely account for a slight temp difference like you are seeing.

[RoundelM3]

Originally Posted by nvmaddog

The drivers side engine bay is hotter than the passenger side nearest the wheel well, this could definitely account for a slight temp difference like you are seeing.

Really...seeing as how the exhaust and turbo are on the right (passenger) side, what is on the left (driver) side that increases the temperature, especially considering the fender well between the wheel/tire and the engine?

[Tpeterson]

The turbo and the exhaust system are on the passenger side.This should make that side hotter. Maybe you made more right turns,heating the driver's side tire up more?

[chattanooga240]

Originally Posted by roundel335

Really...seeing as how the exhaust and turbo are on the right (passenger) side, what is on the left (driver) side that increases the temperature, especially considering the fender well between the wheel/tire and the engine?

Do not have the slightest idea what is causing it, but I had to use my digital thermometer to verify. That driver side wheel wheel is always a few degrees warmer on my car, no dragging brake etc.

[rich8566]

Originally Posted by Troppo

1. Sensor fault?
2. Brake dragging ever so slightly?
3. Wheel bearing?
4. Some kind of tyre fault?

Probably not a sensor since each tire reads the same exact temp cold before during. Suspect a wheel bearing but I had not considered brake drag.

[rich8566]

Originally Posted by nvmaddog

The drivers side engine bay is hotter than the passenger side nearest the wheel well, this could definitely account for a slight temp difference like you are seeing.

That's what I was thinking. Does anyone else have this same observation?

[rich8566]

Originally Posted by Tpeterson

The turbo and the exhaust system are on the passenger side.This should make that side hotter. Maybe you made more right turns,heating the driver's side tire up more?

No - definitely not more right turns.

[Beartato]

Is this wheel facing the sun when parked? That could be it.

[Maynard]

If it is brake or bearing drag, then the extra heat should be much more noticeable at the hub, vs. tire temps. Check after a drive - probably can tell just by hand, but if you have a temp gauge that would be more precise, and let you poke around to see if it is the brake disc vs. bearing area that is getting hotter than the other side. I had a caliper seize in the bore, so some constant pad-drag; the wheel center was almost too hot to touch, very noticeable in comparison to other wheels (noticed it after a longer highway drive, as the pad was smoking by then). Also check brake pads/calipers for visible differences in wear, heat distortion, or brake dusting. If it is looking like brake drag, then a long shot might be something (tire size diff's?) that are causing stability control to constantly try to correct on one side. I'd expect it would also be recording some types of codes, but that is out of my expertise (not necc error codes, but I bet there is a way to pull data on the amount of time the stability system is active, or what adjustments are being made).

[XutvJet]

1) It's possible that you have a toe issue on that tire (either toed in or toed out) which is causing elevated temps. You can easily check for this by driving around for 30 minutes and then running yourhad across the treads. Typically a toe issue will make either in the inner or outer tread blocks hot. If it's really bad, the tread blocks will start feathering.

2) It could be that you take more turns on one side than the other thus increasing the temp on the outside tire.

3) The temp functionality of gauge could be off. Consider resetting the system. If that doesn't fix it, take it in. Keep in mind these sensors aren't that accurate in sub 40 degree temps. They're more for high speed driving where tire temp increase substantially.

Honestly, I wouldn't worry about it too much unless the tires are showing symptoms of a toe issue or the PSI were wildly off as well.

[harma24]

Tire temps is one of the first things I coded. I've observed a difference in all 4 corners from the time the car had 200 miles on the odometer. As I'm now more than 5k miles later, I can assure you that it is not related to brakes or bearings or alignment. I've also seen various tires higher or lower at any given time (although the fronts are almost always warmer than the rears).

I suspect the difference left to right has something to do with road conditions. The front tires generally being warmer I suspect is due to the proximity to the engine compartment.

[XutvJet]

Originally Posted by harma24

The front tires generally being warmer I suspect is due to the proximity to the engine compartment.

It has more to do with the facts that:

1) They're narrower.

2) More weight is on them. 52-54% of the weight is over the front axle.

3) They do the turning.


This all generates more friction and heat compared to the rears.

[2msport]

It is not uncommon for mine to be slightly warmer with the front left tire. You're not the first to ask about it. I thought maybe the extra weight from the driver was the cause. I'm assuming like me, your alone in the car more than you're with someone else.

[AlpsRider]

It is normal on the US model M235i to have more heat on the left (drivers side). My car has always had this same issue since it was new. I'm sure it has to do with the extra coolant radiator on the drivers side front grill. On my car the amount of temp difference depends if I'm sitting in traffic, if it's a hot day etc.

[Questofthetune]

I seem to have my passenger side hotter... uh oh..

[Mike_bmw_m235]

Mine is garage kept square setup and does it too

[harma24]

Originally Posted by XutvJet

It has more to do with the facts that:

1) They're narrower.

2) More weight is on them. 52-54% of the weight is over the front axle.

3) They do the turning.


This all generates more friction and heat compared to the rears.

I'm on a square setup for winter. I'll agree to your other two points, but I've seen this difference at the end of a 5+ hr drive on a highway with minimal steering input. I could see if I were turning a lot, but cruising for hours on an interstate should not account for that much temperature.

[rich8566]

Originally Posted by XutvJet

1) It's possible that you have a toe issue on that tire (either toed in or toed out) which is causing elevated temps. You can easily check for this by driving around for 30 minutes and then running yourhad across the treads. Typically a toe issue will make either in the inner or outer tread blocks hot. If it's really bad, the tread blocks will start feathering.

2) It could be that you take more turns on one side than the other thus increasing the temp on the outside tire.

3) The temp functionality of gauge could be off. Consider resetting the system. If that doesn't fix it, take it in. Keep in mind these sensors aren't that accurate in sub 40 degree temps. They're more for high speed driving where tire temp increase substantially.

Honestly, I wouldn't worry about it too much unless the tires are showing symptoms of a toe issue or the PSI were wildly off as well.

I didn't think about a potential toe issue. I'm sure it's not the left turn right turn thing.

[rich8566]

Originally Posted by harma24

Tire temps is one of the first things I coded. I've observed a difference in all 4 corners from the time the car had 200 miles on the odometer. As I'm now more than 5k miles later, I can assure you that it is not related to brakes or bearings or alignment. I've also seen various tires higher or lower at any given time (although the fronts are almost always warmer than the rears).

I suspect the difference left to right has something to do with road conditions. The front tires generally being warmer I suspect is due to the proximity to the engine compartment.

It's possible it is road conditions.

[rich8566]

Originally Posted by 2msport

It is not uncommon for mine to be slightly warmer with the front left tire. You're not the first to ask about it. I thought maybe the extra weight from the driver was the cause. I'm assuming like me, your alone in the car more than you're with someone else.

That's a possibility.