Wheel and tyre specification for winter tyres

Benmac · 11-05-2021, 09:24 AM

My car is a F31 340i RWD. It's normal wheels are a set of 19" 442Ms.

Earlier this year I bought a set of 18" 396 wheels (standard 8J, ET34) with winter tyres on them (BMW fitment Sottozero Run Flats, 225/45/18 all round).

The manual etc recommends that square set up for winters. Unfortunately the Pirellis were an utter liability. While they looked fine and had a load of tread they were 2013 (IIRC) vintage and had obviously properly gone off.

So, I need some new tyres for the wheels for this winter. I'm just wondering about getting something other than 225/45/18s for the rear (specifically 245/40/18s). This is just to give a smidge more tyre at the rear without stuffing up the rolling radius.

So, questions are:

1. Will I be OK with the 245s on an 8J rim (sense tells me that won't be too much)?
2. Is it fundamentally a daft idea and I should stick to the square set up recommended?

peetee · 11-05-2021, 11:04 AM

These are the ones I currently have on my 2017 F31 335d x-drive. It's a square setup

martin10chk · 11-05-2021, 06:44 PM

What is the motivation for going wider on the rear for winter tyres? You really wont get any more grip. BMW spec square for a reason - its the best setup for winter. 245 on 8J will be fine however.

Ennoch · 11-06-2021, 06:01 AM

I've got a set of staggered 403's on my car but the only reason is because I'm a tart and I want my winter wheels to look like the summer wheels given they spend six months of the year fitted. I don't see the point in speccing nice summer wheels only to fit some cheap black alloys (as many do) to the car for half the year. For practicality purposes however, the cheap black alloys do win out, especially in square. I had the staggered setup through last winter in some pretty deep snow and found them to be perfectly okay, but I did need to stick the TC in dynamic so that it wasn't constantly fighting every little slip. How much of that was down to the rears slipping more than the fronts I don't know. What I can say is that the rears have worn down noticeably more than the fronts have but because they're staggered I can't rotate them, so at some point I'll probably be selling the fronts and then getting another full set of tyres.

kitster · 11-06-2021, 06:55 AM

Always ran a square set myself mainly because its cheaper, can rotate the tyres and smaller footprint when on the white stuff.

At the moment I'm running a 18" square set on 245 Conti 830P which I got from MrWinterWheels, so far been good and reasonably quiet. Wasn't a big fan of the Bridgestone Blizzak LM-32 I had on the F31 very loud and gave little confidence in the snow.

McBeemer · 11-06-2021, 09:22 AM

Quote:

Originally Posted by Benmac

My car is a F31 340i RWD. It's normal wheels are a set of 19" 442Ms.

Earlier this year I bought a set of 18" 396 wheels (standard 8J, ET34) with winter tyres on them (BMW fitment Sottozero Run Flats, 225/45/18 all round).

The manual etc recommends that square set up for winters. Unfortunately the Pirellis were an utter liability. While they looked fine and had a load of tread they were 2013 (IIRC) vintage and had obviously properly gone off.

So, I need some new tyres for the wheels for this winter. I'm just wondering about getting something other than 225/45/18s for the rear (specifically 245/40/18s). This is just to give a smidge more tyre at the rear without stuffing up the rolling radius.

So, questions are:

1. Will I be OK with the 245s on an 8J rim (sense tells me that won't be too much)?
2. Is it fundamentally a daft idea and I should stick to the square set up recommended?

I have the square set up on my 335d with michelin alpins on ... apart from the ground clearance, the car drives like a Land Rover in the snow & is just as confident on frosty roads.
It is the recommended set up & provides tyre pressure settings on the door card too.
I would not waste time & effort on an alternative that is unlikely to provide any improvement apart from a lighter load in your pocket.

2JPW · 11-06-2021, 09:46 AM

I have a square set up on mine too. been amazing in the snow, better with "narrower" tyres as people.have mentioned. I've just ordered a set of Vredestein Wintrac Pros for mine.

HighlandPete · 11-06-2021, 06:20 PM

Quote:

Originally Posted by Benmac

This is just to give a smidge more tyre at the rear without stuffing up the rolling radius.

What is the purpose of a "smidge more tyre on the rear"? What are you after?

Handling will change due to less lateral stiffness in the side walls. Unless you change to a 8.5" rim width. Contact patch 'shape' is not the best for wet and snow in winter months. Remember you don't have a bigger contact patch (if pressure and load are the same), just a different shape.

cramsnik · 11-06-2021, 07:36 PM

Quote:

Originally Posted by 2JPW

I have a square set up on mine too. been amazing in the snow, better with "narrower" tyres as people.have mentioned. I've just ordered a set of Vredestein Wintrac Pros for mine.

Mind sharing where you ordered from?

Benmac · 11-08-2021, 03:16 AM

Thanks all, I think I'll stick with square then. Just "feels" counter intuitive given the summer set up is staggered. That said, the issue of 245s being fine on an 8J but also giving a bit more bulge hence likely movement at the rear is a good point.

Amusingly my wife's C43 also needs a set and lo and behold that asks for 225/45s all round if running winters on 18s (same deal as we have 19s for summer and a set of 18s to put winters on) so I'll be buying 8 of the things!

Now, then what to buy...........

2JPW · 11-08-2021, 11:24 AM

Quote:

Originally Posted by cramsnik

Quote:

Originally Posted by 2JPW

I have a square set up on mine too. been amazing in the snow, better with "narrower" tyres as people.have mentioned. I've just ordered a set of Vredestein Wintrac Pros for mine.

Mind sharing where you ordered from?

Just a local tyreshop. Camskill are always competitive but if I factor in fitting and disposal at £15-20 a corner they're the same price or cheaper.

Probably helps that the Mrs needs 4 tyres on her car too!

cramsnik · 11-08-2021, 01:33 PM

Were they * marked or just 'regular'? If I keep my car I may need a new set myself.

2JPW · 11-08-2021, 02:00 PM

Quote:

Originally Posted by cramsnik

Were they * marked or just 'regular'? If I keep my car I may need a new set myself.

No, not * marked. M+S for.mud and snow.

they aren't runflats but the car drives and rides much better on the 18" winters.

I ran the original ones for 5 yrs and can't fault them. I got up hills that 4*4s were stuck on in the snow.

Worth a look: https://www.tyrereviews.com/Tyre/Vre...intrac-Pro.htm

cramsnik · 11-08-2021, 03:49 PM

Thanks for this, I've recently put the 18" Winters on mine in anticipation of the odd journey into Europe over the Winter months. Completely agree with your observation that the car is better on them. In fact, I'd consider buying a nice set of 18" wheels and running them all year round.

2JPW · 11-09-2021, 02:53 AM

Quote:

Originally Posted by cramsnik

Thanks for this, I've recently put the 18" Winters on mine in anticipation of the odd journey into Europe over the Winter months. Completely agree with your observation that the car is better on them. In fact, I'd consider buying a nice set of 18" wheels and running them all year round.

My new ones go on Friday!

sensible · 11-10-2021, 11:30 AM

I, like a lot of people have staggered 8J front and 8.5J rears 400M wheels and run them with 225 45 18 winter tyres all round (Michelin Pilot Alpin PA4) in a square set up. They work well and are amazing in the snow. Plus this is the recommended tyre size on the plate for 18" M+S tyres. Personally, I wouldn't go bigger on the rear. By enlarging the contact patch there is less downward pressure per square cm, so don't work as well in the snow. You may have a bit more grip in none snowy conditions though.

Benmac · 11-28-2021, 07:16 AM

Just by way of closure I ended up going for a square (225/45/18) set of Michelin Cross Climate 2s. The 396s I have are 8J all round so everything looks sensible in terms of sidewall bulge etc.

In terms of performance they've been bloody brilliant so far. Notwithstanding grip being great there's a tiny bit more squidge than the standard 19" Bridgestone runflats but nothing really more than you'd get going from a worn set (which mine are) to a new set of summer tyres.

However, the biggest improvement is the ride and the noise. I was expecting an improvement given the reduction in size, the Cross Climates not being run flats etc but this is genuinely surprising. Even more so in terms of noise when you consider the more "noisy" tread on the cross climates.

It's a big enough difference that despite my summer set having a few thousand left in them they're getting swapped for something decent and non runflat before they go back on next year!

11-05-2021, 09:24 AM	#1
Benmac Private 55 Rep 84 Posts Drives: G21 M340i Join Date: Jan 2021 Location: Shropshire iTrader: (0)	Wheel and tyre specification for winter tyres - quick check My car is a F31 340i RWD. It's normal wheels are a set of 19" 442Ms. Earlier this year I bought a set of 18" 396 wheels (standard 8J, ET34) with winter tyres on them (BMW fitment Sottozero Run Flats, 225/45/18 all round). The manual etc recommends that square set up for winters. Unfortunately the Pirellis were an utter liability. While they looked fine and had a load of tread they were 2013 (IIRC) vintage and had obviously properly gone off. So, I need some new tyres for the wheels for this winter. I'm just wondering about getting something other than 225/45/18s for the rear (specifically 245/40/18s). This is just to give a smidge more tyre at the rear without stuffing up the rolling radius. So, questions are: 1. Will I be OK with the 245s on an 8J rim (sense tells me that won't be too much)? 2. Is it fundamentally a daft idea and I should stick to the square set up recommended?
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11-05-2021, 11:04 AM	#2
peetee Private First Class 71 Rep 101 Posts Drives: E46M3 E39M5 F31335d E46330iTou Join Date: Jan 2020 Location: UK iTrader: (0)	These are the ones I currently have on my 2017 F31 335d x-drive. It's a square setup
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11-05-2021, 06:44 PM	#3
martin10chk Second Lieutenant 157 Rep 211 Posts Drives: F31 316i, F21 M135i (gone) Join Date: Jul 2021 Location: York iTrader: (0)	What is the motivation for going wider on the rear for winter tyres? You really wont get any more grip. BMW spec square for a reason - its the best setup for winter. 245 on 8J will be fine however.
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11-06-2021, 06:01 AM	#4
Ennoch Colonel 2257 Rep 2,048 Posts Drives: F31 335D XDrive Join Date: Sep 2020 Location: Scotland iTrader: (0)	I've got a set of staggered 403's on my car but the only reason is because I'm a tart and I want my winter wheels to look like the summer wheels given they spend six months of the year fitted. I don't see the point in speccing nice summer wheels only to fit some cheap black alloys (as many do) to the car for half the year. For practicality purposes however, the cheap black alloys do win out, especially in square. I had the staggered setup through last winter in some pretty deep snow and found them to be perfectly okay, but I did need to stick the TC in dynamic so that it wasn't constantly fighting every little slip. How much of that was down to the rears slipping more than the fronts I don't know. What I can say is that the rears have worn down noticeably more than the fronts have but because they're staggered I can't rotate them, so at some point I'll probably be selling the fronts and then getting another full set of tyres.
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11-06-2021, 06:55 AM	#5
kitster Lieutenant Colonel 541 Rep 1,894 Posts Drives: G31 M Sport Join Date: Oct 2012 Location: London, UK iTrader: (0)	Always ran a square set myself mainly because its cheaper, can rotate the tyres and smaller footprint when on the white stuff. At the moment I'm running a 18" square set on 245 Conti 830P which I got from MrWinterWheels, so far been good and reasonably quiet. Wasn't a big fan of the Bridgestone Blizzak LM-32 I had on the F31 very loud and gave little confidence in the snow.
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11-06-2021, 09:46 AM	#7
2JPW Private First Class 56 Rep 198 Posts Drives: 435I M SPORT Join Date: Dec 2016 Location: Midlands iTrader: (0)	I have a square set up on mine too. been amazing in the snow, better with "narrower" tyres as people.have mentioned. I've just ordered a set of Vredestein Wintrac Pros for mine.
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11-08-2021, 03:16 AM	#10
Benmac Private 55 Rep 84 Posts Drives: G21 M340i Join Date: Jan 2021 Location: Shropshire iTrader: (0)	Thanks all, I think I'll stick with square then. Just "feels" counter intuitive given the summer set up is staggered. That said, the issue of 245s being fine on an 8J but also giving a bit more bulge hence likely movement at the rear is a good point. Amusingly my wife's C43 also needs a set and lo and behold that asks for 225/45s all round if running winters on 18s (same deal as we have 19s for summer and a set of 18s to put winters on) so I'll be buying 8 of the things! Now, then what to buy...........
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11-08-2021, 01:33 PM	#12
cramsnik Crustacean denier 390 Rep 579 Posts Drives: M3LR Join Date: Sep 2020 Location: Northants iTrader: (0)	Were they * marked or just 'regular'? If I keep my car I may need a new set myself.
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11-08-2021, 03:49 PM	#14
cramsnik Crustacean denier 390 Rep 579 Posts Drives: M3LR Join Date: Sep 2020 Location: Northants iTrader: (0)	Thanks for this, I've recently put the 18" Winters on mine in anticipation of the odd journey into Europe over the Winter months. Completely agree with your observation that the car is better on them. In fact, I'd consider buying a nice set of 18" wheels and running them all year round.
	Appreciate 0 Quote

11-10-2021, 11:30 AM	#16
sensible Lieutenant Colonel 810 Rep 1,705 Posts Drives: BMW 420i M-Sport Gran Coupe Join Date: Aug 2015 Location: West Midlands UK iTrader: (0)	I, like a lot of people have staggered 8J front and 8.5J rears 400M wheels and run them with 225 45 18 winter tyres all round (Michelin Pilot Alpin PA4) in a square set up. They work well and are amazing in the snow. Plus this is the recommended tyre size on the plate for 18" M+S tyres. Personally, I wouldn't go bigger on the rear. By enlarging the contact patch there is less downward pressure per square cm, so don't work as well in the snow. You may have a bit more grip in none snowy conditions though.
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11-28-2021, 07:16 AM	#17
Benmac Private 55 Rep 84 Posts Drives: G21 M340i Join Date: Jan 2021 Location: Shropshire iTrader: (0)	Just by way of closure I ended up going for a square (225/45/18) set of Michelin Cross Climate 2s. The 396s I have are 8J all round so everything looks sensible in terms of sidewall bulge etc. In terms of performance they've been bloody brilliant so far. Notwithstanding grip being great there's a tiny bit more squidge than the standard 19" Bridgestone runflats but nothing really more than you'd get going from a worn set (which mine are) to a new set of summer tyres. However, the biggest improvement is the ride and the noise. I was expecting an improvement given the reduction in size, the Cross Climates not being run flats etc but this is genuinely surprising. Even more so in terms of noise when you consider the more "noisy" tread on the cross climates. It's a big enough difference that despite my summer set having a few thousand left in them they're getting swapped for something decent and non runflat before they go back on next year!
	Appreciate 0 Quote