Correct Tyre Pressures

I run 38 rear and 34 front on my 80 series if that's any good to ya

Old rule of thumb to get correct pressure is take read when cold ,drive far enough to heat tyres then check pressure again,,if initial correct 4psi increase,,,,check the archives this has all been done many a time.

Paul, Run 32 psi in tyres on our 80 series, 265/75R16 BFG AT's, and have never had a blow out in 120,000 kms. We live in west qld, so summer temps are usually, especially this year, extreme. Do kick them up to 34 - 36 in rear when well loaded, heading for the coast. Drive 79 series all year at 40 - 50 psi, like to have a bit of comfort for part of the year!

happy new year to all...

Paul run same size in the BFG on my st 38 rear 42 front rotate every 5k 60k so far 10k to go never had any trouble .Drop to 38 all round for dirt so hope that helps !

A lot of folks follow the same or similar to what Axel has suggested.

I've got BFG's and run 34 front and 36 rear. No problems.

However there is no "Right" answer. Depends on the Brand of tyre, Vehicle, load, conditions etc etc etc.

I would listen to what Coopers say, then apply the 4psi rule and make adjustments from there.

I am suspect about the Pirelli 4 psi rule. Reason is that different tyres run cool or hot and this varies also with speed. BFG's run VERY cool. My commodore runs much hotter, especially at 180 when I can smell rubber after continuous high speed (when I stop). They get so hot I cannot put my hand on the sidewall. On top of that, I run by BFG's with nitrogen so they run VERY VERY cool. The difference in pressure in teh BFG's is more of a result from road temperature than excessive wall flex so the rule does not repeat itself from one day to next (sunny/cloudy days).

Does anyone know if the 4 psi rule really works for 4WD off road tyres run at modest speeds (I never exceed 130 in my patrol) and usually run at 110 on highway.

I personally think (and I am no expert) that the only thing the 4 psi rule will do is tell me is if I am 'way underinflated'. Also, I run BFG's at around 35 to 40 psi in front and back and wear after 50 thou is on the outsides which to me indicates under inflation on tyres that run cool.

I personally think most people probably run too low for dirt road. I have read lots of posts on this issue, and you know, the more I read, the less certain I become. I agree with whats been posted - there is no universal corrent answer. Wear and tear, and the lowest cost of ownership, is a difficult equation that cannot consider the tyres alone.

Sean

Paul, I have a 2002 GU 4.2TD ST with OEM Bridgstone Dueller AT 693's which I run at 32 psi front and 35 psi rear unless towing. The rear tyres are wearing badly in the centres after 25,000 KM. Bridgstone advise this is a problem unique to Patrols and is only solved by rotating the tyres at every 10,000 KM max. They do not believe it is an over-inflation problem - which is what it looked like to me. When towing I need to go to 38 psi front and 43 psi rear for the Pirelli 4psi guideline to apply.

All very confusing.

Cheers

Kevin

Don't know about you guys, but my GuII 3.0 runs 275/75-16 Bridgestone Duellers and I'm buggered if I can run much UNDER 36 at the front and 44 at the rear!

Anything else and the truck handles like a bucket o'puss on the highway.

Off road, my pressures head south, down to around 22-24 PSI and 30PSI at the rear. These tyres too wear very badly at the front, due to poor caster/camber settings at the factory. Also get stearing shake at 80-90 (depending on tempurature) due to poor shaft-balancing from the factory.

Chris

I run the factory recommended 32psi front 35psi rear on my Tata Safari and the car handles well. The tyres are Indian-made Bridgestone H/T Duellers and so far, with 40,000 kms up, are wearing very well. I've checked the pressures hot, after 200-odd kms on dirt road, and they were close to 4 psi higher than those stated above. I'd suspect that temperatures and pressures would be a bit higher on tar-macadam roads though.