pressure!

4runnercass

New Member
what pressure should i be running in my 31's on a 4runner on the road, ps there desert dualers, ive got them at 32psi at the mo. cheers
 

Traveller

Well-Known Member
A few of us use the '4 psi rule'. Check the pressure when cold, then again once tyres are warm, should
have gone up by about 4 psi. If only gone up 2, maybe drop a pound or 3, if gone 5-6 plus up,
then add some.
This will change with the weight as well as the terrain of course.
Also look at the tyre-is the middle wearing too quick compared to the edges, or visa-versa?
 

millsy

4x4 Earth Contributer
Was thinking about that 4psi rule on the weekend. Wouldn't the air temperature make a big difference on how much extra heat builds up in the tyres, and hence how much extra pressure that produces.

Last weekend when we headed off to Yorkes I had to stop to check pressures because the car was pulling to the left. Sure enough the front passenger side tyre was well down ( low 20's ) compared to the others at 32.

But I noticed when I felt each of the front two wheels for temperature that the drivers side was cool to the touch, and the passenger side just a tad warmer, due to the sidewall flexing.

I know on a summer's day you can barely touch the rubber after some fast driving. So I just wonder how much the cold air in winter is going to stop any significant warming, and so any significant increase in tyre pressures. So the 4psi rule might be very specific to what the air temperatue is on the day. It might be a 1 psi increase on a cold day, and a 6 psi increase on a 43 degree day. Also the issue of road surface - smooth bitumen, grippy bitumen, smooth dirt, rough dirt, . . .
 

bmurray2250

4x4 Earth Contributer
A few of us use the '4 psi rule'. Check the pressure when cold, then again once tyres are warm, should
have gone up by about 4 psi. If only gone up 2, maybe drop a pound or 3, if gone 5-6 plus up,
then add some.
This will change with the weight as well as the terrain of course.
Also look at the tyre-is the middle wearing too quick compared to the edges, or visa-versa?

Agree, this a great rule. To get it in the rough area I look for tyre is sitting flat on the road. The Prado that is around 35lb's in the tyres. The pressure for the front and back may vary to the load
 

Crisp image

New Member
OK another question about preassure.
When driving in the snow (not deep) like on the way to resorts should I drop my pressues a bit? I often go to Mt St Gwinear which is dirt road access and they don't clear the snow down to the road level but leave a layer on the road.
What are your thoughts. (have purchased tire deflators and Mrs Crisp Image wants me to justify why I got deflators)
Regards
Crisp Image
 

croozza

Active Member
OK another question about preassure.
When driving in the snow (not deep) like on the way to resorts should I drop my pressues a bit? I often go to Mt St Gwinear which is dirt road access and they don't clear the snow down to the road level but leave a layer on the road.
What are your thoughts. (have purchased tire deflators and Mrs Crisp Image wants me to justify why I got deflators)
Regards
Crisp Image

Wouldn't hurt to lower the pressures, you can justify the deflators whenever you go 4B-ing as you should always lower the tyre pressure.
 

Grumpy

Moderator
OK another question about preassure.
When driving in the snow (not deep) like on the way to resorts should I drop my pressues a bit? I often go to Mt St Gwinear which is dirt road access and they don't clear the snow down to the road level but leave a layer on the road.
What are your thoughts. (have purchased tire deflators and Mrs Crisp Image wants me to justify why I got deflators)
Regards
Crisp Image

Jeez crispy your slow tell her you justify her buying makeup, it works for me anyway.
 
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