'05 X5 3.0i - replacing factory v-spoke wheels with 20" wheels
 

I have been reading posts for days trying to find out, what I think is a basic question. If the answer is indeed somewhere in here, I apologize in advance for this post.

I have an '05 X5 3.0i with the factory OEM 17" V-spoke wheels. I have found some wheels (replicas, I think - I have read the very informative posting on the buying guide for replicas) that I want to buy. Here is my question(s):

The 20" rims I want are 9.5" wide (I am not going to stagger, for tire rotation purposes). From research I have done so far, I was planning on putting 275/45/20 tires on. Will I have any clearance problems on the front or rear wells? I can't seem to find any specific answers to this question.

I am buying my tires from Discount Tire, and when I went in to research a tire, the manager said that a 20" wheel on the 3.0i X5 will affect the spedometer by 2 mph, @ 70 mph actual speed. Any truth here?

Also, do I need any camber adjustment on the rear?

Any comments is GREATLY apprciated!

Here is the wheel:
http://cgi.ebay.com/ebaymotors/ws/eB...ayphotohosting

:xoutpost: sorry might not be much help in terms of answering the Qs, but JUST DO IT!!! LOL. I would think it would fit no problem. the only thing is the 'non staggered' i guess. someone else more knowledgeable on the wheels can suggest.

You should'nt have any clearance problems with the wells. I put 20s (replicas/staggered) on my 3.0i (had factory 18s). I haven't had any clearance problems. As for the speedometer part..I'm not sure. Replicas usually weigh more than the OEM wheels...so they will have some kind of unnoticable effect..nothing major. But overall you won't run into major issues. Its definately a great investment. Just like the previous poster said, Just do it! haha.

The camber would remain the same with any wheel/tire. Alignments can change only if parts wear, or something gets bent or the alignment guy uses wrenches on it.

Note: demonic forces can alter the alignment when other people drive your car. The demons stuff freeway plants, dirt and wood posts under your X in an attempt to blame the innocent driver. I know this, scientifically, because the driver will very sincerely deny hitting anything. This has happened a couple of time with me, so I know...

It would be a good idea to have a competent alignment done whenever you buy new tires to preserve your investment.

Bad wear patterns tend to continue even after the alignment problem is corrected, so don't put it off or wait to see if a problem develops later.

On my 05 X, the alignment was quite good except for the toe-in. That caused a little drift to the left. Correcting that fixed the drift and made the X steer in that precise BMW way that sets it apart from other able competitors.

I just quit asking questions and bought the wheels from Eurotech Wheels in California. Had them mounted with Yokohama Prada Spec-X 275/45/20 and 295/45/20.

Looks great, wild-one!

The 168s look great! But according to your data, your fronts/rears have different rolling diameters. This WILL cause drivetrain issues - see this recent thread => http://www.xoutpost.com/x5-e53-forum/...hed-tires.html

Either go with the OEM staggered tires sizes or with all 4 same size. As you currently have, the rears are taller than the fronts, which is a no-no.

DKL,

Are you sure this will cause problems on this model? So I need to get... lets say 295/40/20's for the rear? How do I know how my current set up will effect the transfer case, or if it will at all on the 2005? The thread you sent, mentions pre-2004.... Please let me know what you know please...

It doesn't matter if your car is pre or post 2004, all AWD or 4WD vehicles require same rolling diameter on all 4 wheels. If the fronts and rears have different rolling diameters, guess which component have to take up the difference?

Unfortunately, if you want to go staggered, the OEM 275/40-20 and 315/35-20 combo is the only sizes that would provide you with equivalent rolling diameters. I did a quick calculations on all the sizes that you've mentioned:

275/40-20=28.66" approximate rolling diameter
315/35-20=28.68" approximate rolling diameter
275/45-20=29.74" approximate rolling diameter
295/45-20=30.45" approximate rolling diameter
295/40-20=29.29" approximate rolling diameter

As you can see, the OEM staggered sizes have nearly identical numbers.

Super-good info, dkl. I hope to get this fixed today. I am going to ask you a STUPID question, so bare with me: I assume all 2005 X5 3.0i are AWD, correct?

I actually did end up going staggered with the 20" wheels. They wanted $200 more to break the set.

If I stayed with 275/45/20 on the front and changed to 295/40/20 on the rear, will the .45" differential cause problems? The reason I ask is that my wife is the primary driver of the car. I had a '98 328i, that had "low profile" tires, and we spent more time at the wheel repair shop, than we did at home (kidding...) I want the most cushion to avoid as much as possible, bent rims...

As a side note, I bought my tires at Discount Tire, and I happen to know the manager at the location as well. I called him up yesterday and told him of this situation. He told me that DT does extensive research on vehicles, in relation to manufacturer models, wheel/tire size ratios, OEM reccomendations, etc. He said these sizes of tires that they put on for me were recommended, on the 3.0 with 20" wheels... after my story, he sounded really concerned (I was in a near panic) and he said he will calling into their "technical services division" ASAP this morning. He went as far to tell me that they have put these same tires on the same X5 3.0 models previously, and to date has not heard of any problems.

DKL, you have provided excellent information. I will post what we figure out today, in case it may help someone else.