Tyre Pressure in Wet Weather???

[sickgm]

Hey Guys,

I have had some scares on the wet roads up here in NSW over the last few days.

I am running GY MTR's and they are a little low on tread on my 4runner, but I am experiencing lock up on the wet roads and it is not even with excessively heavy breaking???

Any Ideas? Would running a lower psi be an option??? or not??? I am currently running 40psi front and rear?

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[Goatse.AJ]

I'd be running a lot less than 40psi. Start at 32psi and go from there.

[sickgm]

Is 40 psi too much for road driving? This is what the clowns at the tyre place told me????

[bogged]

40 would be a good pressure for patrol or heavy 4b..

front or rear lockup... little low on tread - how low is little low

[sickgm]

Well, low I would think it has about 5mm tread depth left????

Locked up in the front........ does that help?

[v6hilux]

In the wet, wide tyres are scary, as they tend to float across the water better and loose traction.

My thinking is extremely over-inflated wide tyres with the center of the tread bulging would be better, but it's just a theory and could be dangerous.

Not much else I can say, except change to cheese cutters till the rain stops or just slow down, because if your current tyres have scared you, then that's better than loosing it.

Another thing to consider is your front shock absorbers. Perhaps they are letting you down.

[sickgm]

Thanks for the advice, but what do you mean by the shock absorbers? Is that and indication that they could be worn ?

[Mr Sausage]

shocks can make a huge difference in braking and lock ups, I'd start with checking them first
v6hilux makes some excellent points

[sickgm]

Yeah my mechanic did mention that they were worn a little, but that it would be worth changing? ? ? ?

So there is something I might get another opinion on.

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[Slunnie]

My thinking is extremely over-inflated wide tyres with the center of the tread bulging would be better, but it's just a theory and could be dangerous.

We used to do this in Karts before they allowed wets. 50psi in the slicks and off we'd go. This said, that type of tyre is an entirely different construction but the theory is good. Im not sure it it would be anywhere nearly as effective with a road radial as the face of the tyre doesn't really curve all that much like it does with a slick, and I wouldn't put money on it generating more wet weather traction on the road.

[alien]

i run my zuk at 20psi on road (31's) and its going fantastic... i did however have some work done and the shop, in good faith, inflated them to 32psi all round - the ride was bumpy as on the way to work that morning, and i was sliding around every roundabout and corner... so i let the tyres down to 20psi and suddenly all was good again - tons more traction.

I think its more about the tyre having some give in it to wrap to the road surface more under loads, but i dont know - all i do know is that lower is FAR better in the wet for a lightweight zuk.

[ozy1]

i would definately adjust your tire pressures, i run about 32-34psi and that is in a heavy gq patrol, so id say start as 32psi and see if it improves,

also get a suspensiuon check done at pedders, they are normally cheap and doesnt take long,

[sickgm]

Thanks for your help guys, will lower the tyre pressure and have the shocks checked out.

I am just a little concerned about taking it to a suspension specialist as the first time i did they want to replace everything in the front end and then my trusty mechanic said they were full of it. Final verdict was an idler arm and thats it!

[ausyota]

If the front is locking up easily then also check your back brake adjustment and load sensing prop valve.

[bazzle]

If the front is locking up easily then also check your back brake adjustment and load sensing prop valve.

Very good info, esp on a lifted 4bee. Tyre pressures can make a big diff too.

Sadly as off road tyres wear you get into the carcass rubber that doesnt grip very well .

Bazzle