245/45/18's on E39?

[Paul in NZ]

All E39 M5s are fitted exclusively with 18-inch M Parallel Spoke II cast alloy wheels featuring a Satin Chrome finish. These wheels, which measure 8x18-inch (front) and 9.5x18-inch (rear) and wear staggered 245/40ZR18 (front) and 275/35ZR18 (rear) tires, are specific to the E39 M5.

your tire are slightly bigger than even the M5....

[AngryPopTart]

My post isn't getting a response in the other thread... I think it's just getting buried. So...

Short Version: Can you run 245/45/18's on all four corners of an E39 with 8" wide wheels?

Long Version: Like I said, my bro ended up buying my Paps' E39, and he decided to pull his 18" M-Par replicas off his E34 and run them on the E39. They are 8" wide rather than 8.5" and he has 235/45/18's on the front wheels because the 245/45's they came with originally, hit the front struts on his E34. So can he put the 245/45's back on the fronts now that his wheels are on the E39 or will they rub on the E39 as well?

[AngryPopTart]

All E39 M5s are fitted exclusively with 18-inch M Parallel Spoke II cast alloy wheels featuring a Satin Chrome finish. These wheels, which measure 8x18-inch (front) and 9.5x18-inch (rear) and wear staggered 245/40ZR18 (front) and 275/35ZR18 (rear) tires, are specific to the E39 M5.

your tire are slightly bigger than even the M5....

That doesn't really answer my question. The 275/35 ends up having a larger diameter than even a 245/45, while the 245/40 is obviously a tad smaller. Is the 245/45 going to rub in the front? That's what I want to know. I'm assuming that M's are slightly lowered... although, I remember now that this 528 has the M sport package so I'm guessing it sits roughly the same, except that it has 8.5" Style 5's all the way around, IIRC.

[BMWDriver]

I don't think the M package changes anything on a stock setup except for the cosmetic aspect. I just don't think it's doable on an assembly line to lower the suspension or to put different parts for it. Manufacturers want to keep it as simple as possible and meet the customer's needs.

So, the M package is a nice marketing tool to sell you to the idea of looking like you have a nice sporty M car without the added advantages of a real M5. That without having to spew out too much dinero.

Unless customers start to crave for a lower suspension often enough, which would rather surprise me, then they'll offer it as an option too. Otherwise, demanding sports drivers like us must have it done or buy an M5.

[Paul in NZ]

I don't think the M package changes anything on a stock setup except for the cosmetic aspect. I just don't think it's doable on an assembly line to lower the suspension or to put different parts for it. Manufacturers want to keep it as simple as possible and meet the customer's needs.

So, the M package is a nice marketing tool to sell you to the idea of looking like you have a nice sporty M car without the added advantages of a real M5. That without having to spew out too much dinero.

Unless customers start to crave for a lower suspension often enough, which would rather surprise me, then they'll offer it as an option too. Otherwise, demanding sports drivers like us must have it done or buy an M5.

the mtech susension is slightly lower than standard.BMW must have a very well organised company,as there are many many variations of the same model,with different engines ,transmissions and an option list a mile long....

[AngryPopTart]

One thing is for sure, it does not turn as quickly as my E34. I never liked that about the E39. Anyway, I guess there just aren't enough cars running around with this size for me to get an answer.

I guess I'll just have my brother swap the rears to the front to see if the 245/45's hit or not... now, I wonder why he and my Paps had me waste my time finding out... why didn't they just swap them and find out themselves. Grrr!

[BMWDriver]

Well, we also benefit from learning something about the e39, which is a potential next car for many of us here.

[Hypr5]

I honestly don't see why they WOULDN'T fit trouble - free.

I have 245/40/18 all around and I had a little rubbing under hard cornering, but my car is seriously slammed on coilovers and the wheels are spaced nearly 10mm. With a stock mtech suspension, I see no reason that a ~5mm diameter increase would pose any sort of problem. It DEFINATELY wouldn't be a problem in the front, but you could always roll the rears IF you had slight rubbing.

[AngryPopTart]

The rears are already working. It just has the 235's on the front because they hit the struts when they were on the E34. The 245/45/18 looks REALLY good on the E39. It fills the fender well up really good in the back... at least on this one, with the M-tech suspension. I think the only problem it will have is rubbing the front fender under hard cornering... hitting a bump. Actually, even my E34 with factory wheels and tires snagged the inner fender lip while hitting a dip during hard cornering on a downhill. My Paps is a bodyman so he just corrected it within a few moments, but I was surprised it hit. Maybe it's because my suspension is so worn out.

[Hypr5]

The e39 is designed a bit differently.

My front tires are tucked in the fender and as I said, the wheels are spaced amost 10mm, and there is still no rubbing - even under hard cornering.

On the e34, the wheel is more flush with the body work. I may be wrong, but I seriously doubt there would be issues there.