Emergency Tyre Question - again but with a twist

[bennyfx]

Hey Guys,
really random question here -

A) in an emergency, if i am carrying a full sized rear wheel/tyre (265/35/19) on an OEM 220M wheel

if one of the front tyres goes to shit, will the rear (wider) spare fit on the front? only to get me to the nearest tyre centre.

or

B) if i was to carry a full sized front wheel - in an emergency, would i be able to use that on the rear

vice versa



- its raining cats n dogs outside and i really dont want to take off the two wheels to check.... if i dont have to.

thanks!!!!

[msan]

In my experience with competition pkg rims (which are slightly wider) you can do either. Put a rear wheel/tire on the front or put a front wheel/tire on the rear.

If you have aftermarket brakes this logic no longer applies.

[pubo]

Both situation would fit but the car would drive pretty bad at speed.

Got two of them "accidentally" swapped when I changed all the rubbers few years back. Found out after days of dealing with the weird drive, kinda like bad alignment with a bit of shudder. Had to go back and insist them to redo the balance and alignment.

Fyi, I have stock 245/45/18 front and 265/35/18 rear

[bennyfx]

great good to know - thanks heaps guys.... the other option is to get an x5 space saver

BMW 36116768861

and a hub centric ring spacer
74.1mm to 72.56mm

then a space save spare tyre.


- by the time i sort all of that out, it would cost the same as an OEM wheel....

not worth it, to save a few kg and a tiny bit of space...

[bennyfx]

Originally Posted by msan

In my experience with competition pkg rims (which are slightly wider) you can do either. Put a rear wheel/tire on the front or put a front wheel/tire on the rear.

If you have aftermarket brakes this logic no longer applies.

awesome!! good to know. thanks for the quick response

[E90M3_Guy]

This was an interesting question that resulted in several good replies. I have 359 M comp pack wheels, so it's good to know they could be swapped to the other axle.

I thought of getting a space saver spare, but it's rather inconvenient in terms of the loss of space in the boot. Carrying a spare would be very beneficial on a trip - which is the very time you need the boot space for luggage!

[bennyfx]

Originally Posted by E90M3_Guy

This was an interesting question that resulted in several good replies. I have 359 M comp pack wheels, so it's good to know they could be swapped to the other axle.

I thought of getting a space saver spare, but it's rather inconvenient in terms of the loss of space in the boot. Carrying a spare would be very beneficial on a trip - which is the very time you need the boot space for luggage!

agree 100% but

i would much rather squash a full sized spare/space saver in amongst all the luggage/pram, toys, shit etc and have options to get off the highway and to a hotel for the night

verses

stranded by the side of the highway in the middle of the night with no options, waiting for roadside assistance to come (if they come at all)

just a bit of piece of mind

[E90M3_Guy]

Originally Posted by bennyfx

agree 100% but

i would much rather squash a full sized spare/space saver in amongst all the luggage/pram, toys, shit etc and have options to get off the highway and to a hotel for the night

verses

stranded by the side of the highway in the middle of the night with no options, waiting for roadside assistance to come (if they come at all)

just a bit of piece of mind

On balance, I think you're right. I'd like the security of having one when driving out of town. It seems to be relatively easy to buy a space saver from an X5 at a wrecker. Does anyone know where to buy a hub centric ring 74.1mm - 72.6mm? Does BMW make them? I read of part number 2 777 118? There are unbranded ones on eBay for between $8 - 17, but would you trust them?

[bennyfx]

Originally Posted by E90M3_Guy

On balance, I think you're right. I'd like the security of having one when driving out of town. It seems to be relatively easy to buy a space saver from an X5 at a wrecker. Does anyone know where to buy a hub centric ring 74.1mm - 72.6mm? Does BMW make them? I read of part number 2 777 118? There are unbranded ones on eBay for between $8 - 17, but would you trust them?

they have aluminium ones on ebay for that sort of price.

dont forget - its just a temporary solution - you wouldnt actually be driving for pro longed distances or speed on the space saver anyway.

if i cant track down a spare full sized - im going to head down the x5 wheel route. a few wreckers have them for about $250

[E90M3_Guy]

I have a new question. Someone posted that the wheel size needs to be at least 18" to clear the front brakes. However a BMW dealer sourced the recommended space saver wheel for an E90 M3 owner and it's 17".

This wheel has never been on the car but will a 17" wheel be OK?

[bennyfx]

hmmmmm do you have the BMW part number? might have to make a call

[E90M3_Guy]

Originally Posted by bennyfx

hmmmmm do you have the BMW part number? might have to make a call

The wheel part number is 36 11 6 768 203. It's a 3.5x17 with ET8. I've taken lots of measurements and I'm not convinced it will fit.

The clearance between the outermost part of the brake caliper and the inside of my 19" wheels is around 15 or 16mm. I calculate that the clearance with 18" wheels would be 3mm at best. So a 17" wheel would only fit on the front if the offset was suitable.

[bennyfx]

yeah having scoured through alot of the forum, + m3cutters UK forum i think you'd struggle with a 17. usually everyone opts for the 18" version from the e70 x5

BMSpares? i think in melbourne has a few in stock for around $250 and from there you'd need a $10 ebay job hub centric spacer then you're good.

you feel like being a guineapig? haha

[E90M3_Guy]

I'm happy to be a guinea pig but I'm not ready to buy yet. Still got more research to do. I visited a BMW dealer today and they said the space saver spare for my E90 M3 is a 3.5x17" with part number 36 11 0445 045 which is a wheel with a 125/80x17 tyre. Price is not too bad at $A604 + GST. However that's a different part number to the 36 11 6 788 203 wheel that another dealer sold to an owner.

Anyway, my mechanic is convinced a 17" wheel will not fit and I agree after taking more measurements. So that's not an option. Pity because a 125/80x17 has a circumference that is only 3.5% different to our M3 tyres whereas the X5 space saver 155/90x18 is 12% different. OK on the front but I don't think the diff would enjoy that for long.

Also, the X5 wheel is 5" wide which is not as compact as the 17" with a 3.5" width.

[Shan75]

I would like to get spare also. Read up about the X5 18" wheel also. Be interested to see where this goes....

[E90M3_Guy]

I took the plunge today and bought an X5 space saver spare from a wrecker in Melbourne and ordered a hub centric ring on eBay. It will be quite a while before I have time to report how it goes, so some patience will be required.

I had a choice of a 2015 X5 18" steel wheel or a 2005 X5 19" alloy. I chose the 19" with BMW part number 36 11 6 756 858. It's a 5"x19" ET40 with a 155/80x19 tyre. The circumference is very similar to a 155/90x18. However the ET40 means it will sit inboard 26mm more than the ET14 18" steel wheel. I guess this shouldn't matter too much for low speed emergency use.

I chose the 19" alloy over the 18" because it's possibly lighter, the hub centric ring should fit more cleanly, and the standard wheel bolts might fit better (as I heard that standard wheel bolts on a steel wheel might insert too far.

Next steps are to source a nice tyre bag to avoid placing a dirty tyre in the boot and also make sure my scissor jack will fit into the BWM jacking point. If not, a BMW jack from a wrecker would ensure a perfect and safe fit.

[Shan75]

Nice. Please keep us informed. I also looked at that alloy wheel and thought maybe hub centric ring was not required for it? See how you go.

[E90M3_Guy]

Well I did a test fit yesterday and it fitted fine on the front and just cleared the front brakes in terms of offset. I took the car for a drive and there were no issues on full lock in either direction. Shan75 - you were correct that a hub centric ring is not required.

This 19" space saver spare is noticeably bigger than a 245/35x19 with a 241 mm bigger circumference. The car has to be raised more to allow fitment. However the tyre does clear all the guards although it does consume a lot of boot space and can't be pushed fully to the back of the boot due to its width.

I tried to attach photos without success.

[bennyfx]

nice to know - so to confirm you ended up going an x5 spare wheel in 19"?

BMW part number 36 11 6 756 858.

do you mind sharing how much the part cost? i'm gonna get one this week. got some km's to drive coming up

thanks

[E90M3_Guy]

Originally Posted by bennyfx

nice to know - so to confirm you ended up going an x5 spare wheel in 19"?

BMW part number 36 11 6 756 858.

do you mind sharing how much the part cost? i'm gonna get one this week. got some km's to drive coming up

thanks

Yes, that's the part number for the 19" alloy from a 2005 X5. The wheel is made in Mexico. I paid only $160 but the 18" steel version was $260. I can't explain the price difference. I'll try to attached photos of how it looks on the car, how the wheel only just clears the front brakes in terms of offset plus the amount of boot space consumed.