C30 tyre pressures

[Smith2698]

Hi, need a bit of advice, running 225 40 18s on my 2.0 diesel and was wondering what sort of tyre pressures everyone runs on these tyres currently got 33psi in, is that too soft? Nothing in the manual is of any use, seems to only go up to 215 45 18. Cheers

[Kev0607]

38psi ideally, 36psi at a minimum.

There isn't much of a sidewall on those tyres being lower profile. You want plenty of air in them so you don't buckle the alloy when hitting unavoidable bumps.

[Welton]

Originally Posted by Smith2698

Hi, need a bit of advice, running 225 40 18s on my 2.0 diesel and was wondering what sort of tyre pressures everyone runs on these tyres currently got 33psi in, is that too soft? Nothing in the manual is of any use, seems to only go up to 215 45 18. Cheers

This has reminded me of an issue years ago when I wanted to change from 205/50/17 to 225/45/17 (I think) - I contacted Volvo UK and my insurers and got a big fat 'no' which would have left me having to use a specialist mod-friendly insurer instead so I never took it further.

The basic response was "you can only use tyres tested and approved by the Factory" and those sizes would all be listed behind the fuel filler flap.

I'm not sure about your size there, have you checked the fuel flap list?

[Kev0607]

Originally Posted by Welton

This has reminded me of an issue years ago when I wanted to change from 205/50/17 to 225/45/17 (I think) - I contacted Volvo UK and my insurers and got a big fat 'no' which would have left me having to use a specialist mod-friendly insurer instead so I never took it further.

The basic response was "you can only use tyres tested and approved by the Factory" and those sizes would all be listed behind the fuel filler flap.

I'm not sure about your size there, have you checked the fuel flap list?

That's a good point. I think the original poster is having issue finding his/her existing tyre size in the owner's manual. That's may well be because he/she has the wrong tyres fitted to the vehicle?