What tyre pressure should I use?

[Fazz]

My LBX has 18 inch tyres (or "tires" as the manual describes them...sigh). According to the manual, the inflation pressure should be 33 psi. When I first got the car, the pressures were higher than that but I didn't let air out, thinking the factory setting must be OK. I check them every month and they gradually declined, as you would expect. I've had the car 6 months and the tyre pressure warning light has come on. But the tyre pressure monitor shows that all 4 tyres are 33 psi. I confirmed this using a couple of independent pressure gauges. I had to pump the front tyres up to 35 psi, and the rear to 38 psi, to get the warning light to turn off and the pressure monitor indicators to change from amber to white.

So now I'm confused. Should I adopt the settings in the manual (33 psi all round)? Or should I retain the original factory settings (35 psi front and 38 psi rear)? Anybody else facing a similar dilemma?

 

[ColinBarber]

Use whichever pressure you feel most suits your needs in terms of comfort, fuel economy and your type of driving. I’d start with the settings in the manual, not what someone may have incorrectly set them to (factory would have put them much higher than recommended for shipping but they should have been correctly adjusted at PDI). 
 

Set them to your desired pressures, then reset tpms so you correctly get alerts when they drop 10% below that level. 

[kevinc23]

All 4 of my tyres needed a few pounds of air this week due to the low temperature. I had the tyre info on the media player while I put air in. I noticed that it doesn't update instantaneous, it maybe scans the tyres every 5 minutes or so. You should be able to reduce your 38 psi to 33 psi without any dash warning.