Tyre Pressure

[Exdee]

Hello folks,

Just wandering what tyre pressures people with the following wheels drive at?

front: 225 45 R17

rear: 245 45 R17

I think I have 32 all around and was wandering if its safe to increase it. I've read about people driving as high as 38 and 40. Any recommendations?

[ironrose]

I keep the front ones at 36-38 and the rear ones between 38-40 depending on the season and the type of usage.....

32 sounds way low on the R17s

Optimum pressure table should on the door pillar when you open the drivers door.

[Exdee]

Thanks for your reply. The pillar says 30 F and 32 R. I have gone for 36 all around at the moment and seem to find it okay. I'll increase the rear ones to 38 when I check again in a months time.

[normski2]

I wouldn't recommend having tyre presssures different to those indicated for your tyre size.

Keep a close watch on your tyre wear for signs of bellying out ( worn too much in the middle - pressure too high) or bellying in (worn on the edges - pressure too low).

My tyre sizes state 41 front 38 rear> think I'll stick with that. Kind of expensive not to?

Like ironrose says " they are shown on the door pillar".

[F.A.]

.

My tyre sizes state 41 front 38 rear> think I'll stick with that. Kind of expensive not to?

Like ironrose says " they are shown on the door pillar".

Normski, your door pillar sticker must be different to both of ours then as both cars state 35 for the front ( 225/40R18) & 38 for the rear ( 255/40R18). The figures that you have quoted look like the ones recommended for the IS220d which state 38 for the front (225/40R18) & 41 for the rear (255/40R18), but the other way around!

I have covered 18000 miles since I purchased our 2011 model (exactly a year last Sunday) and have been monitoring the tyre pressures on a weekly basis. I found that 35 psi for the fronts were under inflated and cause excessive wear on the outer and inner edges of both my front tyres. I increased the front pressures to 38psi which has stopped the excessive outer & inner wear. The rear tyres have worn evenly at 38psi.

[normski2]

Yeah, sorry mate, tired twits should not post stuff eh!!! This is what comes of being used to looking at 220D stuff!!!!

Dunno why but I got my figures back to front ....35 on the front and 38 on the rear.

But I will check it tomorrow in daylight. LOL :)

[normski2]

Interesting FA. I will investigate the 38/38 approach and see how it goes. Thanks for the knowledgable tip.

[Exdee]

Right, I've been through the owners manual and came across various tyre pressures for various speeds and various tyre sizes. For less than 100mph 35F and 38R was the recommended cold tyre pressure for both 17" and 18" stock wheels. I think I am going to fill mine up to 38 all around and see how that goes as per F.A's set-up.

Can't believe the dealer under-inflated my tyres so much. Just had them replaced in June and they look a few years old already.