There is. It's concerns axle weight and loading and tyre rating (max inflation pressure). These tyres are stock size so stock pressures should apply. The tread pattern is different but shouldn't make too much difference. Like Stirlingmoz said, you can have a bit of a play, but generally around what's recommended for standard tyre sizes. Odd wear is a potential issue. The muds on the syncro can be run as low as 28 on the road due to the stupidly heavy block pattern, and down to 15 to 18 on the rocky roads but at those pressures you run the risk of the tyre coming off the rim unless you're really careful. I run them mid 30s on the front, low 40s on the rear. Generally 5 to 10 psi difference front to back.
I was just quoting an average from all the stickers I've seen, triggered by stirlingmoz running 30/30 and even thinking he'd over-inflated the fronts. I thought I'd poke him into looking into it. I doubt a general formula would apply to our buses where most of the weight is on the rear axle?
It sort of does Zed, I went down that rabbit hole when I first decided to run non standard AT tyres, going to 15 inch from stock 14" T3 rims. Trouble was it involved weigh bridges coz the vehicle wasn't in standard trim etc etc. In the end the figures came close to the standard pressures anyway, but I ended up just running with what was comfortable within a safe range, still with the higher pressures on the rear by about 8psi. Why did I bother? Well, the factory recommendation for the 4wd T3 is to NOT run tyres that have a radius difference of 2mm across the axles. Something to do with winding up the transmission through the VC! So then you get sucked into a tyre rotation regime every 5k miles blah blah blah. I wasted hours of my life on that! Now we just drive it and fix it when it breaks
The stock rear of the Kombi fully loaded is 44 psi according to the sticker on my bus. And 42 unloaded at the rear, with 29 psi on the front both times.. On non stock tyres , my findings are 45 on the rear and 35 on the front . My dad used to tell me of driving a Landrover Defender by mistake in 4x4 on metalled roads, every now and then there would be a massive bang as the tension in the suspension let up as the wheels skipped.
Hiya mate could you do me a favour please and get me the distance between the tread of the front tyre and the front edge of the jacking point I’ve got side bars on mine so may not have enough clearance
I’m away with work at the moment but back home for the weekend. Will run a tape measure over it for you.
Not the greatest photo. I was holding the tape measure with one hand and the camera with the other. Nothing left to press the button Oh and that’s part of the wheel clamp wrapping around the tyre above the tape measure. The tape measure is resting on the tread face. Hope it assists. Stirlingmoz
