Our first 'mod' to our X3

Hey all,

New member here (not totally new to BMW's but haven't owned before, just helped buddies with theirs etc.).

We got my wife a great deal on a 2004 3.0i 6spd X3, with 30k miles... Last year! Previous owners must have left it parked after the first year or so (18k miles per year is pretty normal here in Houston).

Anyway we got the thing cuz the wife wanted an SUV for practicality, and my car's a coupe (not even a fastback - oh I wish it were so). I tried to sell her on getting a nice fun station wagon but no dice. When we found a 6spd X3 it seemed a good compromise - I can't stand driving autos and the road manners are pretty reasonable. To justify the SUV/SAV part to ourselves, we promised ourselves beach / woodsy campouts etc. - and the X3 was not too bad in the sand at lake travis / matagorda. However, it was time to ditch the Turanzas and I decided to look into something a *little* better for mud / sand etc.

I wanted to post here because I searched and couldn't find much info. I was having trouble finding all-terrain (not rock-crawly but multipurpose) tires in similar-to-stock sizes (the Turanzas were 235/55/17), but looking at the wheel wells I thought we could go a bit bigger. At first, I was tempted by some 245/60/17s, which would have gotten us an extra ~1.2" in ground clearance. Later, I found some Toyo Open Country AT's in 235/60/17 and went with that as the safer option. I got them mounted tonight and thought I'd mention that I'm very glad I didn't go with a 245mm width - there isn't a lot of clearance to the shock body on the fronts. I think a taller tire in 235 on the stock 17"ers might be fine, next time I will look into 235/65 or up. Another option is of course spacers, and I may consider that too.

I am probably more excited about offroading our X3 than most, but I figured some might like to know it's possible at least... If I find a cheap set of beater rims, I might try taller / wider + spacer etc., but I don't want to experiment toooo much with the everyday setup given my wife's level of patience for me modding what is ostensibly 'her' car .

Speedo error will be your friend. Actually might not be that bad since size variances do exist from one manufacturer to another. Did you do the math before you bought?

Yes, I'm fully aware of the speedo error issue, but in this case it's around 3 mph error at 65 mph indicated, so not enough to worry about. Discount Tire has a convenient calculator that shows 65mph speedo error (so I didn't even have to set up my own spreadsheet).

If I were to go to really large tires at some point I'd have to figure out how to tell the ECU as 'guessing' around a 10+mph speedo error might not go well with cops some places.

So far drives fine on the road, I'll have to find some mud to complete the testing.

Check your friendly wrecking yard for X3 rims. There was a lot of flooding damage in the South East and unfortunately lots of cars were caught up in it and totalled out. The rims of course would be just fine. You folks had a drought (may still have it) but your neighbors did not. Most "auto recycling yards" are hooked up these days so parts are easy to find. Lots cheaper than OEM! The X3 also had an 18" factory option as well as a staggered option with the sports version. You probably won't want either one of those, but it helps to know they are out there and are "real" X3 wheels. For more info on X3 tires and wheels check with Gary the moderator on the Tirerack thread here on Bimmerfest -- under Bimmerfest forums.

Would love to see some pics of the larger tires....

Here's a start; you can see the size difference from the previous Turanzas. No issues since install; but as you can see these are not soccer-mom-mobile tires, they have some decent offroad knobbie to them... and of course, consequently, some additional road noise.

Are you more curious how apparent the size difference is when standing 10 ft back or details of tire clearance? Happy to help out, as there's always a chance (though slim) enough of us will offroad these to get some aftermarket goodies coming our way eventually...

Also final photo here:
http://www.facebook.com/media/set/?s...3&l=97b909b110

Thanks. I'd most like to see a view from about 10 feet back. I've been wanting to make my X3 stand out a little from all the rest. Love the knobby look of those tires too!

You haven't had any issues with the ASC and getting into top gear on the highway?

Hm, I'm not sure if you mean DSC instead of ASC?

You raise a good point in the last part though, if I had an automatic I would worry. 6-speed manual here - and no issues to report w/ DSC or stability control or whatever.

Like I said, only remotely noticeable issue is the increase in tire noise, which was A. quite good with the Turanzas considering the crap roads where we live, and B. even with the Toyo A/T's is nowhere near, not even the same neighborhood, as the noise levels I get from the Dunlop Direzza Z1 Star Specs on my car (not an X3 or even close, but trying to lend a little objective credibility).