Replace All 4 Tires?

[fnp93]

This is my first Xdrive experience. I noted my rear tires are seriously worn, but my fronts look alright. They are factory staggered so I cannot rotate. Traditionally on my RWD BMW’s I’ve owned in the passed with a staggered set I would replace the rear tires twice to ever one tire change in the front. Can I do this with x-drive or is this a bad idea?

Here is a pic of my treadwear. And yes it’s very bald haha.

First pic is rear tire second pic is front tire.
The remaining two pics are the tire wear bars.

[fnp93]

Update, tread depth on front tire is 6mm

[cwickberg]

Always replace at least both tires on the axle... it's OK to split replacement between front and rear... the xdrive system won't notice difference between the front and rear tire treads, but can notice it side by side especially with performance control

[Allworth]

Originally Posted by fnp93

Update, tread depth on front tire is 6mm

Your rear tires are looking to be below safety standards and needs to be replaced anyway.
If your front tires are 6mm it is acceptable to put new rear tires, 2mm thread difference is within xdrive tolerance.

[maxwmiller]

fnp93, not sure how you use the car and what tires are on it but 6mm on the tread means the front tires should be ok for a while. Once you get to 3mm of tread remaining, performance (especially in wet conditions) is noticeably degraded, but you should have at least a year before getting to that point.

Obviously if you can afford, it is usually cheaper to replace all four tires. Up to you in the end

[05X3lover]

If this were my wife's X1 I'd replace all 4. Yeah you might get a bit more time out of the better set but I'd rather look for some tire deals, and then do all 4. Vehicle will drive better and make things a lot less complicated that way, imho.

[fnp93]

Update I went ahead and replaced all 4 with Michelin ps4’s.

They are factory staggered 225/40/19 and 255/35/19. Ordered exact size as on the door sticker

After allowing tires to break in I’m having some concerning issues. 1st or 2nd gear start, does not matter. There is a noted judder. Also under heavy throttle in second gear traction control kicks in. Never had this problem before, even with completely shot rear tires.

I measured each tire by hand front and rear overall height are within less than 1/4 inch (within BMW’s 1% rule)

I attempted resetting throttle adaptations, battery, I uninstalled MHD and even tried adding some extra air to rear tires to even the 1% difference.

There are no codes after checking with MHD or Carly.

Funny enough, when I’m pulling away from somewhere with the wheel turned the problem is non existent.

Am I missing something?

[fnp93]

I planned on trying x delete but bummer, not available for x1!

[maxwmiller]

Nice, PS4 are the way to go.

Three thoughts re: traction control.
1) how long have you had the tires 2) what climate are you in and 3) did you get you car re-aligned?

I consider 500 miles to be the break-in for new tires. Could be that they're just not fully concentric yet. Second, Michelin recommends them to be used in temperatures over 45*F for optimal performance. Third, if they aren't sitting properly, obviously this would affect traction.

And when you say judder, what do you mean? Traction control in these cars is pretty good, nearly any slip can set it off. I have the AWD 2.8i so spinning tires at a start isn't a concern for me but a shake when taking off usually would indicate a problem, assuming you're on a decent road surface.

[fnp93]

Yes all 4, the grip and road noise are fantastic. I had ps4’s on my e92 and loved it!

Tires currently have approximately 1,000-1,500 miles on them

No alignment was performed, car tracks very straight.

Strangely it only happens when starting from a stop gear makes no difference. It happens between 8-12mph. It happens both with and without TC. It feels as though it’s trying to shift power from the front from the back but it seems to studder. When moving, no issues.

Fast forward, if I’m in second or third gear and I accel hard from a low rpm, no studder is noted but traction control cuts in big on the power and light flashes. Flip off traction control and no problems.

Never had this problem on my last set of tires which were continentals.

I have had spacers on over a year without issue, I pulled those off last night just to see if it would make a difference. While improved a little it’s not resolved.

I’ll try to post a video of what’s going on!

[fnp93]

Measured again without spacers less than 1/4 inch difference between overall rolling diameter of the front a rear tires. That leave a 0.99% difference

[fnp93]

Video of TC kicking in

https://youtu.be/qiu79jM7AGU?feature=shared

[Westies]

Originally Posted by fnp93

Video of TC kicking in

https://youtu.be/qiu79jM7AGU?feature=shared

From my experience this is normal when tuned. My TC will kick in under full throttle in 1st and sometimes 2nd gear, especially if the road surface is poor. Did not occur before I started pushing more power than stock. The higher boost map the more TC kicks in.