Emergency Wheel for E53 with 20" style 87

[wpoll]

Originally Posted by Qsilver7

But as mentioned above...the spare tire well will only fit either the 17" (possibly the 18", too) tire/wheel combo. The 19" & 20" wheel/tire combo will stick up to far to allow the cargo floor to fit properly in place.

It doesn't apply in the case of the OP's question but also remember that the 4.8is (and maybe the 4.6is - not sure) have bigger brakes and the factory 17" rims won't clear the callipers. Neither will the 18" rims. Hence the use of the "space-saver" wheel on these cars...

[Overboost]

Originally Posted by wpoll

It doesn't apply in the case of the OP's question but also remember that the 4.8is (and maybe the 4.6is - not sure) have bigger brakes and the factory 17" rims won't clear the callipers. Neither will the 18" rims. Hence the use of the "space-saver" wheel on these cars...

Thank you to everyone, you have educated me on the spare tire/emergency wheel sizes and fit. I have no brake upgrade so my 18" full size spare will serve the purpose. Thanks again for taking the time to answer my questions.

Just for grins, I ran the numbers for the 19" emergency wheel with the run flat 19X180x80 tire.

18/2 + 255*0.55/25.4 = 14.52
19/2 + 155*0.80/25.4 = 14.38
20/2 + 275*0.40/25.4 = 14.33
20/2 + 315*0.35/25.4 = 14.34

[Qsilver7]

[oldskewel]

All sounds good. The last thing to check, depending on what non-OE wheels one might have, is that the lug bolts are compatible between the regular wheels vs. the spare. Different wheels might have different seats.

And if you ever found yourself in a situation where the spare wheel would not fit over the front caliper, it might be worth trying to swap the good rear wheel to the front, then see if the spare would fit on the rear, with a smaller caliper.

[PropellerHead]

Originally Posted by oldskewel

And if you ever found yourself in a situation where the spare wheel would not fit over the front caliper, it might be worth trying to swap the good rear wheel to the front, then see if the spare would fit on the rear, with a smaller caliper.

That there is a *fine* idea!

Edit: Ohhhh.. but now that I consider it.. This would be difficult on the side of the road with the stock jack. It could be done perhaps with a jack stand or something to hold the rear up. Each to his own level of risk tolerance of course.

My E70 19" wheel solution was good for the sizes that Overboost came up with. I do have an adapter since the wheel hub is a different size on the two models. That's another key consideration for those with aftermarket wheels: If it's needed, be sure to keep a spare adapter for your wheel once you've fit it. They can be difficult to remove while roadside from a wheel hub fresh out of service.

Incidentally, I went through nearly 30 YEARS of having ZERO tire issues until Dec 2016. That 'fluke' of a problem while on vacation became something of a habit when it happened *again* in two *different* rentals.

[Overboost]

Originally Posted by PropellerHead

My E70 19" wheel solution was good for the sizes that Overboost came up with.

All the credit for the math diameter of the different wheel/tire combinations goes to oldskewel. Nice information

[oldskewel]

Originally Posted by Overboost

All the credit for the math diameter of the different wheel/tire combinations goes to oldskewel. Nice information

And my friends all said I was wasting my time paying attention in 4th grade math class. I knew it would help some day.

In all my years of driving I have never actually had a tire go flat on one of my cars. Once happened on my GF's car, and once in a friend's car, but never mine.

One other thing I do just to cover even more bad possibilities is to carry a little tire plug repair kit - just in case, for example, the wheel lock key does not work, etc. Enough preparation and it is guaranteed to never be needed.

[e39_touring]

Originally Posted by PropellerHead

That there is a *fine* idea!

Edit: Ohhhh.. but now that I consider it.. This would be difficult on the side of the road with the stock jack. It could be done perhaps with a jack stand or something to hold the rear up. Each to his own level of risk tolerance of course.

(

No need for a jack stand - just do one wheel at a time. With front tire flat, 1) put spare on back, then 2) put the back wheel you removed in step 1 on front.

[PropellerHead]

Originally Posted by e39_touring

No need for a jack stand - just do one wheel at a time. With front tire flat, 1) put spare on back, then 2) put the back wheel you removed in step 1 on front.

See there? That wasn't even math and you made it look easy.

[Fifty150hs]

Originally Posted by oldskewel

And my friends all said I was wasting my time paying attention in 4th grade math class. I knew it would help some day.

In all my years of driving I have never actually had a tire go flat on one of my cars. Once happened on my GF's car, and once in a friend's car, but never mine.

One other thing I do just to cover even more bad possibilities is to carry a little tire plug repair kit - just in case, for example, the wheel lock key does not work, etc. Enough preparation and it is guaranteed to never be needed.

Had a blow out in my wife's 740iL at 100 mph. Must say it was a very non-event. A bang some smoke, some rumbling and pull off the road. Truly sold me on bimmers.