Tyre Presure - JEEP on 22"

pugheaven · 17 Jul 2015 at 14:47

Very important question here, what PSI would you guys put in a Jeep Grand Cherokee Ltd 2.4 ton with 285/35/22's on it? I got caught out bigtime tyesterday.

Took it into get two new front tyres (one was knackered due to a ball joint think it was wearing) and I was going to keep the second tyre as a spare in the boot (as 22 inch wheels aren't exactly common)... BUT there was a split... the guy asked what pressure I'd been running and last two years around 34PSI... he laughed (as they all did) and said I needed a minimum of 40PSI in them... I was amazed, as I thought that was VERY high.

Anyone any experience or advice, so pumped all over the four to 40PSI, but I'm not convinced... however open to opinions?

JonF · 17 Jul 2015 at 14:59

Like these?

JRS · 17 Jul 2015 at 15:03

I would read the socking great sticker on the car (should be in one of the door shuts if it's like almost every single other car on the market), and put however much air in that it tells me. Unless the wheels are aftermarket, in which case I'd go by the guy who sold me the tyres for them.

Dr Who · 17 Jul 2015 at 15:37

JRS said:
I would read the socking great sticker on the car (should be in one of the door shuts if it's like almost every single other car on the market), and put however much air in that it tells me. Unless the wheels are aftermarket, in which case I'd go by the guy who sold me the tyres for them.

Indeed, but tyre pressures don't need to change just because you change wheels, the tyre pressure is decided by the weight of the vehicle, which presumably hasn't changed much by fitting aftermarket wheels.

Use the stock pressures or a few PSI more not exceeding the high speed pressure in your manual.

red eye · 17 Jul 2015 at 16:15

Dr Who said:
Indeed, but tyre pressures don't need to change just because you change wheels, the tyre pressure is decided by the weight of the vehicle, which presumably hasn't changed much by fitting aftermarket wheels.

Use the stock pressures or a few PSI more not exceeding the high speed pressure in your manual.

This and auto data chart says 36psi for 20" 22 is not listed in 2015.

Kaeo · 17 Jul 2015 at 16:36

Anywhere between 34 and 38 will be fine, dependant on load.

pugheaven · 17 Jul 2015 at 18:16

Cheers people. I've read a few things and the sticker for the stock 17's was 34PSI... so that means nothing if I've got the aftermarket rims on which never do state what the pressure should be as like said it's dependant on the vehicle. However, so 40PSI doesn't seem that mad then by all accounts. Cheers.

Antony101 · 17 Jul 2015 at 18:52

My old Corsa recommended at least 39 PSI in the front tyres, even more if carrying 5 people + luggage.