Wheels

[D6Stevie]

I kept the 18’s from v50 and intend tomorrow to put em on c30 since the tyres were all less than &00 mile and pirelli p7’s its got on. I have searched the forum without definitive answers 🤪
Will the 18’s (Standard volvo Medusa alloy) fit the c39 it’s 1.6D v50 was 2.0Diesel.

[lockstock]

Originally Posted by D6Stevie

I kept the 18’s from v50 and intend tomorrow to put em on c30 since the tyres were all less than &00 mile and pirelli p7’s its got on. I have searched the forum without definitive answers 🤪
Will the 18’s (Standard volvo Medusa alloy) fit the c39 it’s 1.6D v50 was 2.0Diesel.

pretty sure the centre bore, offset and pcd are identical. at 63 something, 52 and 5x108. So provides the tires give you the same rolling radiuS, it should be okay. there are calculators online to check. have a look also at the back of the c30 and v50 alloy. the specs will be on them... u can then verify they match....

[andy_d]

Originally Posted by D6Stevie

I kept the 18’s from v50 and intend tomorrow to put em on c30 since the tyres were all less than &00 mile and pirelli p7’s its got on. I have searched the forum without definitive answers 🤪
Will the 18’s (Standard volvo Medusa alloy) fit the c39 it’s 1.6D v50 was 2.0Diesel.

main dealer will have the SW download to allow 18 inch wheels ,IF they physically fit, that will sort the speed/miles for you ,

[lockstock]

Originally Posted by andy_d

main dealer will have the SW download to allow 18 inch wheels ,IF they physically fit, that will sort the speed/miles for you ,

why? if you change to a larger wheel, you go with a different width and profile tyre to achieve the same rolling radius. Whilst it may be possible to recalibrate the speedo and tacho for a different circumference tyre, it will likely screw your gear ratios a little and usually the gear ratios and power map of the engine are all considered together by the manufacturer.

Also, why put yourself in the position of needing a software update to switch back to 17" wheels at some point.... this is bizarre advice......

[lockstock]

Originally Posted by andy_d

main dealer will have the SW download to allow 18 inch wheels ,IF they physically fit, that will sort the speed/miles for you ,

If I want to change my gear stick for a different size one will I need a software update for that too? how about sear covers, will a different colour need a software update. I've fitted new headlight bulbs, hallogen. Do you have Vida so I could do a software update?

[iainmd]

Originally Posted by lockstock

this is bizarre advice......

It's not bizarre it's quite correct. To run 18's Volvo require two modifications. A software update that adjusts the ECU to the different rolling circumference so that the ABS system and speedo are aligned. I can only assume that the 16 and 17 inch stock wheel options have a similar rolling circumference but the 18 tyre option doesn't.

The second thing factory 18" cars have modified is a steering limiter. Presumably to prevent rubbing due to the wider tyre size.

Details here.

[lockstock]

Originally Posted by iainmd

It's not bizarre it's quite correct. To run 18's Volvo require two modifications. A software update that adjusts the ECU to the different rolling circumference so that the ABS system and speedo are aligned. I can only assume that the 16 and 17 inch stock wheel options have a similar rolling circumference but the 18 tyre option doesn't.

The second thing factory 18" cars have modified is a steering limiter. Presumably to prevent rubbing due to the wider tyre size.

Nope. stock 17s. 205 50 R17 vs 225 40 R18.. same circumference, no difference required for speedo. Now if you wanted to run 215 45s or some other odd size, it will be out by a couple of %... It is possible I guess Volvo used a 215 45, but on a 7.5 rim this would be odd, but hey volvo are odd sometimes!

[iainmd]

If you read the link I posted you'll see that Volvo use 215/45R18 as standard. Gives a 2% difference in circumference.

[lockstock]

Originally Posted by iainmd

If you read the link I posted you'll see that Volvo use 215/45R18 as standard. Gives a 2% difference in circumference.

sorry mate, I missed where the OP posted what tyres were on it...... Everything I've posted is correct, If you take a look at my post you will see your reply is a little redundant, cheers though. Also, my advice is best practice. changing circumference of the tyre to use a bigger size wheel is never recommended even if Volvo did decide to do it. Not being a dick it's just a lot of people on here give 'half an answer' about wheel size questions, which could end up with people making mistakes or wasting money.

What matters is what wheel and tyre combo are currently on his car and what tyres are on his new wheels. They can then decide whether to change tyres or get a software change. But a sofware update should be the back up plan for obvious reasons. Maintaining the correct rolling radius is best.

[RPB]

Bought 17inch Sculptor alloys from a main dealer when I got my V50. They have 205/55 winter tyres and I use them to replace the 215/45 18’s with Bridgestones on.
Dealer never mentioned software but I was going the other way!