Reader help: what tyre pressures should I run for my Toyota LC200?
A reader wants help determining the correct tyre pressures for their toyota LandCruiser 200 Series when driving on-road and in sand.
I’ve been using Robert’s excellent 4WD Handbook to help understand my tyre pressures. In Chapters 4,5,6,7 you suggest pressure reductions using the vehicle’s placarded pressures as the starting point. It is a simple concept that is easily remembered.
However, my 200 series LandCruiser has a placarded pressure of 230kpa (about 34psi). After the first set of tyres wore badly, my Toyota dealer said that 40 – 41 psi was the correct highway pressure; and to alter tyre pressures from that starting point. They said the 34psi was a gravel road pressure, reflecting the more typical use for this vehicle.
My question is: which pressure do you mean your readers to start from?
This checking came about because I need lots more sand driving experience and want to find my own suitable tyre pressure. I measured tyre wall height at 40psi (ie 155mm / 100%), then reduced pressure till it was down to 75% (ie 116mm). Air pressure was then 14psi. Tyre looked OK, contact patch was 75% longer, and it seems like a good pressure for my vehicle, load and tyre.
What do you think of this?
10 Comments
Thanks – a good run-down.
I was surprised to find the placard recommendation radically different on my MU-X as against a mate’s Colorado 7. You’ve explained why.
When I started outback driving I ran off Adam Plate’s rule of thumb to drop 30% off the placard figure and never had a problem. That figure was developed around Oodnadatta.
Cooper’s put out a guide that’s worth a read as it covers other road conditions: https://www.coopertires.com.au/media/1400/cooper-drivers-guide-tyre-pressures.pdf
Yes 30% off placard for dirt is not a bad way to go. I like the % rules as vehicles vary so much absolute numbers make little sense.
What’s your take on the 4(or 6) psi rule when it comes to sand Robert?
I see a few inadvertanly drop a hot tire down to 18psi or lower then find them checking if they have a flat once the tire has cooled down.
I agree with the premise of leaving some room for dropping pressures. Another issue is low pressures can significantly lower clearances. I drove a short legged navara through the Simpson where anything under 22psi in the front had it incessantly surfing on its front bash plate.
Wasn’t aware of any such rule. Yes overnight in the desert pressures can drop very significantly for example. Ground clearance is reduced, yes, but it also means you can drive slower with less suspension compression so it’s not as bad as it seems. And the clearnace reduction isn’t much. Navaras aren’t noted for great clearance to begin with anyway.
4 PSI is often quoted on forums. Note though that the Coopers tyre pressure guide says it’s for bitumen only.
If your tire pressures increase by 4psi after extended road travel you have your pressures about right. Any higher and your pressures are low (for your current conditions) . Any lower suggests your pressures are high for the prevailing conditions.
Definetly for the d40. This one was lifted.
Hi Robert, An interesting read thank you. Did you get this around the right way. I always understood that a low pressure wore on the outside and the inside of the tire wore the inside of the tread.
Quote:
“The second is to find a very flat bit of concrete and the tyre widthways
with chalk, then drive forwards straight for several metres. The chalk
should wear evenly. If it is worn on the inside of the tyre that’s
underinflation, on the outside that’s overinflation.”
Thanks Matthew
Could have been better phrased. Changed to:
If it is worn on the outside of the tyre’s width that’s underinflation, on the centre of the tyre is overinflation.
What is the maximum weight a caravan could be to tow behind a 2005 Toyota Landcruiser 4.6 Petrol V8 and what should the ball weight be?
You’ll need to read the owners manual and find the maximum tow weights and other info.