Tyre pressures on grand vitara 2004 235/60 R16

[momo]

Hi peeps hoping for some feedback/advice on tyre pressures.... i have just bought a grand vitara 2004 with the tyre size 235/60 R16 100h it has Bridgestone dueler sports tyres. One had 50 psi (the max on tyre states 40) the rest had around 45. The vehicle sticker states 26! I have an older vitara with 195s ive always kept these at 32psi. Any thoughts? These are wider than the others obv and want the most fuel efficient possible but dont wanna wear em out unevenly either. I've set them to 32 for now. I only go off road occasionally now. Any ideas appreciated

[Jordi]

If its predominantly road miles i’d just stick to the manufacturers recommended pressures.

[momo]

Thanks Jordi, tyre or car manufacturer? I assume you mean stick to the pressure sticker on the door frame? Seems very low 26psi? 40 on the tyre seems better anyway it's not a major issue was just curious what others did

[Larry]

Are the tyres standard size or oversize?

If they are standard then the 26psi on the car is about right, if they are oversize then you may want to go slightly lower.

I would imagine that the tyre size and subsequent volume of air inside it is actually big relative to the gvw of the car which is why they are recommending 26psi rather than a more average 32psi as per a standard car tyre.

The only real way to tell is to monitor tyre wear over several thousand miles and see if you are:

wearing the inner / outer edges (pressure too low)
wearing the centre (pressure too high)
wearing evenly across the width of the tyre (correct pressure)

hard cornering and roundabouts etc. will also contribute to uneven wear so its not an exact science!

I believe the 40psi that's on the tyre is the maximum allowable pressure, so if for instance they were fitted to a car that called for a pressure of above 40psi under certain loading conditions, these tyres wouldn't be suitable.

I read once on a land rover forum about a test where you draw a chalk line across the tyre and drive a few miles, if the pressure was correct the chalk line would be evenly worn off, if not you needed to adjust pressure to correct. I've never tried this so can't say if it would actually work.

[momo]

Cool. Like the chalk line idea will try that thanks!

[RichyP]

I normally run mine on 30psi (235/60) but normally carrying barrels of water sacks of animal feed ect so extra weight. Im with Jordi and Larry 26 psi for normal driving about sounds about right