Front wheel spacer / steering feel question..
 

3.0i, with 18" wheels. Like all 18's, and all 19" fronts, they are 48ET. I've never understood the exact use of the BMW ET #, but I do know that it describes the distance from the wheel's hub facing, to the outside edge of the rim. The rear wheels from a staggered set of BMW 19's or 20's have an ET of 45. Because the E53 X5 has hub flanges that stick out to the same point on the front as the rear, this means the wheel's outside rim edge will push out 3mm more.

I also know that when one buys wider BMW wheels, ALL of the extra width goes to the inside of the wheel. The car gets fatter.. underneath. They do not push out to the outside more. The ET numbers remain the same.

I'm about to go from 18"x8.5 all around, to Style 132 19"x9" all around. The ET is still 48. The extra half inch will pooch to the inside of the car. I'm adding 30mm wheel spacers to the back for sure (for looks). The question is, should I add wheel spacers to the front (again, this is for looks), and if so, how many mm?

Wait.. there's one more factor to consider; Wheel spacers push the wheel facing out, which means the push the steering axis point out too. The farther out the wheel's center line is from the steering axis, the more "dead" it will feel in steering.

I'm thinking about going with 10mm spacers in the front and that the steering axis to wheel center line point won't be effected, because my new wheels will be 1/2" wider to the inside. 12.5mm is one half inch.

What's your opinion on looks; No front spacer? 10mm front? Other? (Rember the rear's will have 30mm spacers, with ET48 wheels)

Opinions on the steering analysis?

Thanks guys.

Spacers should be fine, make sure they are hub and wheel centric, especially in the front.

Not quite true. Although the wheel will be 1/2" wider, by maintaining the same et48 some of the 1/2" will be inside and some outside. By doing the math, the extra 1/2" (roughly 12.7mm) would give you about 6.3mm more outside and 6.3mm more inside. Thus by maintaining the same offset, the width is evenly split around the center and should maintain the steering feel and bearing loads.

I have used spacers for years in many cars (Audi, Porsche, BMW) and have no problem with their use. The caveat is that only good hub-centric spacers are used (H&R for example). But the front of BMW's with the steering and suspension geometry is very sensitive to drastic offset changes. I run 10mm rear spacers on the X5 and might try 15's with the winter setut, but I won't add front spacers. I tried spacers on my 528 and while it looked better, the front end just never felt right so I went back to no spacers at all.

Are you sure about the extra width being split in two? My old 17" wheels were really narrow and they didn't stick way in. On the outside, they look just like the 18's do now. However, what you are saying makes perfect sense. It would be smart to spllit the diff so that the steering remained "factory".

So what you are saying is that I should just get the new wheels and do nothing with the fronts because they'll stick out just a little further, and that for the rear I should switch to buying 25mm spacers instead of 30mm.. eh??

Yes I'm sure about the extra width of the wheels. I pulled out my calculator and did the math to get those numbers.

My rule of thumb has always been to try without the spacers first to see what you have. My winter wheels are virtually identical to what you're thinking about getting- only 18's. But 9" wide with et45 offset. The fronts could stand to go out a bit but I'm happy as it is. The rears could go way out. I've got 10mm spacers back there and could easily go to 25. My mistake was just not getting the same wheel in an et20 for the rear since it was offered as both a 20 and 45mm offset. But at least this way I can rotate the tires.

So I'd suggest getting the wheels and use either the 25 or 30mm spacer for the rear (Can't tell you if the 30 will work sorry). Mount up the wheels, then decide if you need the extra 10mm spacer for the front. My guess is no, but that's your choice based on how it fits.

And don't forget the longer bolts to go with the wider spacers.

Cool. This was exactly the feedback I needed. I'll order the rear spacers only and wait on the fronts. I agree that 5mm should be avoided on the fronts because you don't get hubcentric. Gotta go 10mm to start getting that.

On the rears, I'll get the H&R DRA kit. In either 25mm or 30mm this kit bolts to the car's hub flange with included silver bolts, then you bolt the wheel to the spacer with the car's stock bolts. You pick up another quarter pound of weight from the extra bolt heads and the steel thread inserts, but it is a veeeery solid setup. Plus the added weight is at the center of the wheel.

Yeah.. 25mm or 30mm. Torture decision. I've determined that 30mm is not too much. The problem is that if you go 30mm and no front, you're introducing a tad more understeer. I replaced the suspension on the Coupe and drastically reduced understeer (and actually have oversteer now). But I'm sticking with stock suspension on the X so I don't want to induce much of a change. But If I do get front spacers after all, I'll probly wish I'd gone with 30mm in the rear and not 25mm HA!

Thanks for the advice. :thumbup:

Hi,
Did you end up going with 25mm or 30mm? How do they look? I'm looking to get spacer for my 4.6is. I'm only interested on getting them on the rear wheels. Right now, I can't decide to get the 20mm, 25mm or the 30mm. I think the 30mm might be too much. I'm thinking more for the 25mm. Any suggestion/advice would be appreciated.

thanks

I went with 25mm. 30mm would have been "perfect", but I should point out that I have a 3.0i and non staggered wheels. Your 4.6is may have a different hub flange offset (distance out). I know your wheels will be out about 3mm more. Someone else here with a 4.6 or 4.8 should confirm the wheel spacing and ET numbers for you, but I believe that 30mm would not be too much for your setup. Can't go wrong with 25mm either.

If you go with 20mm you won't be able to get the kit that bolts on to the hub first and then reuses the wheel bolts (highly desirable). Only the 25mm and 30mm kit has this feature. Read through the thread for part numbers. I'd go with at least the 25mm.

What is the final word on front wheel spacers? I like the way the rear spacers look but am hesitant till I find someone who likes them in the front? Thanks

Front Spacer
 

I never got the front spacer. I had installed 25mm on the rear and had thought about adding a 5mm to offset the rear a little but never had the chance to follow through with it. Sorry, wish I can help on the front spacer.

:dunno:

No fronts yet either
 

Yeah, I haven't done the fronts yet either. Based on all the data, my hunch is that 10mm front spacers would not make the steering feel too odd on these heavier vehicles with the large heavy wheels. I think it is still worth doing. They are cheap enough.. just try it and see how she steers.

Looks wise, they so need it! I have rear spacers on the Z3 Coupe and the X5. Now when I look at other cars that don't have spacers they just look so funny / odd. My friends new 335 just looks.. well, I kind of feel bad for him. "Common dude, we need to fix your car".. hehehee..

These X5 need the fronts pushed out just a little further too.

So why am I waiting? Black bolts. Painting the longer silver bolts is not working out. I tried it on a front spacer kit for the Coupe. Paint instantly comes off the first time you torque the bolts. Even tried baking the paint on. I'm still looking for long black bolts. Can't find any leads. The only other option is to switch to wheel studs and buy high end (very expensive) black anodized nuts from TC Kline Racing. The problem is (besides the cost), they only make bolts for the 1,3,5 series. X5 takes larger studs / nuts. Anybody have any leads?

My OEM wheel bolts are black... have you tried the dealer?

Your BMW bolts? Right.. they're all black, but when you add a spacer that is between 5mm to 20mm thicker, you then have to switch to bolts that are that much longer too.. or they won't reach the hub. BMW doesn't make longer bolts. So that means going after market. Most guys buy the H&R longer bolts, but these are silver.

In this whole wide world one would think there's just gotta be someone producing black longer bolts. :dunno:

Ok, I found some from Turner Motorsports. But here is the classic problem... these will only work on non X5 BMW's with 17mm bolt heads. The X's take larger bolts.

http://www.turnermotorsport.com/html...ACK-WHEEL-BOLT

I am tempted to just try it, just hoping someone who has used them on the front will respond with their experiences. It would be nice for the bolts to be the same color too, when I put the rears on I realized they didn't match. Thanks for your feedback.

Hey TurnAround,
As I have OEM 19" 132's like you (mine are staggered though) and like you I am considering putting 25mm or maybe 30mm spacers on the rear could you post a couple of pics showing before and after pics of the rear end?

Their's plenty of chit chat on spacers but very little in the pic department. Also if anybody else out there has 19" rims (staggered) with spacers could you post pics please and indicate what size spacers you have fitted.

Given that I don't believe you put spacers on the front how did you go with bolt colours in that H & R's only come with silver bolts and of course the front ones are factory black. If you left the bolts unchanged are you happy with the look?

In advance thank you.

Here you go. Kind of rainy today for pics.

I ended up with only the rear spacers, and skipping the fronts. This was because of the silver bolt issue. As it turns out, leaving the fronts alone and going with a rear 25mm spacer makes the car very balanced looking (imo). I'm extremely happy and would do it again in a second. It had zero effect on worsening understeer (the usual concern with widening the rears). In fact, it improved the general handling of the car.. definitely. Not ranting / gushing here.. just sayin'.. this is one of the best mods you can make to your BMW. I am so pleased with it for improved looks and handling, I cannot imagine owning a BMW without this mod, and really.. I see unmodded X5's and realize now how "doofed in" / wrong the rear wheels look. (sorry guys..its fer yer own good to say this! hehhehee..)

Stock black bolts on the front... and the rear. 25mm and 30mm spacers have nuts in them. You can reuse your factory bolts. It works sooooo slick!

Now, keep in mind I don't have staggered wheels. One half of the extra width on a wider set of staggered rears will push to the outside. What are they.. a half inch wider? So that's one quarter inch wider then, which is 5.5mm wider. So.. factor that in to your decision. Said another way, if you do not widen the fronts, then view these pics with the rears 5.5mm wider. 30mm spacer.. then they'd be 10.5mm wider than the pics.

(Edit) Ohh.. almost forgot. I wish I had gotten 30mm spacers. I DO like the slightly pooched out look on the rear. The 30mm would have been even more ideal. I'll see if I can find a pic of my Coupe with the wider rears.


:thumbup:

Ok, here's some pics of the Coupe with 25mm rear spacers only. Now.. these cars already have a fat arse, so 25mm here, would be like 40mm on an X5. The moral to this story.. go with the 30mm spacers on any X5! hahahaa!! :wow:

Thanks for that, I appreciate it. Definately looks better with the rear spacers on. I think when the time comes I might go with 30mm. Nice cleaning looking ride you got there.

Just one last thing, I'm a little confused now re the black factory bolts. I wouldn't think that they would be able to be used if I go with 30mm, no ??

With 25mm and 30mm, the spacer is bolted onto the hub using provided bolts, the wheel is then bolted onto the spacer using the factory bolts. This is the actual style spacer that I wanted, but 25mm spacer on my 285 rear would stick out too much, IMHO.

H&R's largest spacers are 25mm and 30mm. 25mm is juuuuust thick enough where they can incorporate 20mm thick steel nuts inside the spacer itself. Those nuts become receivers for the factory wheel bolts. First, you bolt the spacer to the X5's wheel hubs using (5) steel silver bolts supplied with the spacer. Torque them to the same 103ftp that you normally would. That is the last time you bolt them to the car.

Then, you place the wheel onto the spacer.. and rotate it an inch to in between the hub bolts, where the new nuts are. Now bolt on the original factory black wheel bolts into the H&R nuts housed inside the spacer, and torque them to the same 103ftp. Its ingenious.

The same is true for the 30mm spacer.

They can't do it with the 20mm, 15mm, 10mm, or 5mm spacers because they are too thin to accommodate the thickness of the nuts inside.

The front wheels would stick out too far with these same 25mm spacers, so that means you can't use this same design trick. Fronts usually call for 5mm, 10mm, or 15mm at the veeeeery most. In any of those cases, you are "stuck" with having to use super looooong H&R supplied silver bolts that go all the way through the spacer into the car's wheel flange / hub.

Your other option is to switch to wheel studs. This reverses the arrangement so that you are threading "nuts" onto the studs. THen you can order the studs to what ever length accommodates the spacer. Some guys swear by this. The thing is though.. the nuts that go on the studs.. just plain 'ol don't look like a BMW. That simple. And.. they're silver too. TC Kline sells super high end stud kits with black powder coated nuts. They look cool. Really nice. Still not BMW looking, but.. worth a look. But.. they are very expensive.

Thanks dkl, that clears it up for me.

Resurrected...

I have 132's staggered...anyone go with a 10 X 25mm setup for the front and rears...

I'm getting ready to lower the X as well with B & G springs...