Toyo Proxes STII and PSA regarding wheel locks...
 

After one year and 10k miles on my 2011 X5d with 20" Dunlops, I made the switch to Toyo Proxes STII non-run-flats last week. My initial motivation was to have a M+S rated tire for occasional winter trips to the Sierras. I planned this far ahead, and ordered the spare tire option. I originally thought I would go with the Continental DWS, however their inconsistent availability turned me off.

While the 20" Dunlops on the standard X5 suspension make for a firm ride, I found it to be acceptable, and the stiff sidewalls necessary for running flat effectively raised the spring rates for crisp (for an SUV) turn-in and minimal body roll in the corners. I was hesitant to potentially lose this, however I do have another tool in the shed for fast windy road driving. The Dunlops are showing some wear, but there is enough tread for them to go back on at the end of the lease, so off they went.

I was instantly, and continue to be, shocked at how much better the ride is with the Toyos at the same 35 PSI all-around that I ran on the Dunlops. And while I never considered the Dunlops to be a 'loud' tire, I am more aware of wind and engine noise now, so the Toyos must be more quiet. Add in a 420 wear rating (240 for the Dunlops), that they are made in the USA (Germany for the Dunlops), and their relatively low price (~$1k installed for all four), and I am EXTREMELY pleased with these tires.

Steering is slightly lighter now (per spec sheets, the Toyos are ~10lbs lighter than the Dunlops), and feel is about the same, but there does seem to be a bit more softness in the handling. I have also seen the stability control light flash a few times in the last week when going through the twisties - had never before with the Dunlops. That said, they only have 250 miles on them, and the rubber mold nubs have not worn off yet.

Overall, could not be more pleased.

Oh, and the PSA regarding wheel locks: If your vehicle has them, know where your wheel lock key is. When I took delivery of the X5, there was a blister pack of wheel locks in the front console. Never being anywhere that the wheels would be at risk, I tossed them onto a shelf in the garage and forgot about them. Turned out that the wheel locks WERE installed, and the non-locking wheel bolts where put back into the blister pack - with the wheel lock key - and put into the center console. Didn't find this out until my first trip to the tire store. Why the dealer or PDC that installed the wheel locks did not put the key into its designated spot in the 'tool kit', is beyond me. Just glad I didn't find this out on the side of the road somewhere...

got those on my 50i within 3 weeks of delivery - very happy with them.

Recently did the tire pressures again because of the changing temps. I followed the manual and it says 32psi usually. Only if you're going over 100mph or have 3rd row should you be at 35psi, but never all 4 at once. Mostly 32/35. With the staggered 20s, it's supposed to be 32/32.

Do you have differing instructions?

In the driver's door jamb, my 2011 X5d with sport package and 20s, and without 3rd seat, indicates a recommended 32/35; 38/41 for over 100 mph.

BMW prides itself with design and manufacturing of vehicles with 50/50 weight distribution, then they undo that balance by recommending lower front tire pressures, and putting 'staggered' wheel/tire set-ups on sport package and M cars; the former for inducing 'safe' understeer, and the latter for vanity. In the past, on LCA E36 and E46 M3s, myself and others would run a rear wheel/tire on front for a 'square' set-up at the track for more front grip, and therefore more balanced handling and more even tire wear. With my driving style on the twisty roads that I frequent, with the X5 I find more front tire pressure goes a little way towards the same thing.

I am not suggesting that people should experiment with factory-recommended tire pressures; in my original post I was merely pointing out that tire pressures were not a variable when comparing ride quality and handling between the Dunlops and Toyos.

Too me, that much variance in the suggested setting becomes a range of pressures for me. If I am going on a long trip or in the mountains, I'll set them to the upper end of that range. I too bump the front closer to the rear for better front end turn in, etc.

I adjust for tire wear over time too. But I seldom see more wear in the middle of the tires, implying that more pressure won't hurt. As far as ride quality, it is faaar better than the Z4, so no issue for me to set them high.

I run 35psi on all four corners.
My 2011 X5d w/sport and 20"s (no 3rd row) recommends 33/33 on the door jam...

Strange that BMW would change their recommendation during a model year, but it just goes to show that tire pressures are not an exact science.