AT Tyres Feedback @ ExplorOz

AnswerID: 282328 Submitted: Friday, Jan 18, 2008 at 17:34

Smudger replied:

On the side of your tyres it will tell you the max tyre pressure. Use that. I run my boat trailer at nearly 60psi. Any lower and the tyres will get too hot, that's what causes blowouts.

Reply 1 of 5

FollowupID: 546808 Submitted: Friday, Jan 18, 2008 at 17:35

Smudger posted:

Re Above: I assumed that you were talking about tyre pressures on your caravan.

FollowUp 1 of 1

AnswerID: 282335 Submitted: Friday, Jan 18, 2008 at 17:48

Robin Miller replied:

The optimum pressure for the tyre in any vehicle is directly related to the weight the tyre is carrying.

If your case it looks like 2 tyres each with 900kg

Your tyres probably have stamped on the side of them the load and pressure needed for that load. just ratio in thru and that is best.

Higher than this is often used to reduce fuel use but makes suspension harder and wear unevenly , so thats a trade off

Click Image to Enlarge

Robin Miller

Member: My Profile

Reply 2 of 5

AnswerID: 282389 Submitted: Friday, Jan 18, 2008 at 21:20

splits replied:

Teago

I had an interesting talk to a tyre company on the phone recently and some of the things they said were (a) the pressure is related to the weight as Robin Miller has just pointed out (b) a 1 psi increase all round will increase the load carrying capacity by 70 kg and (c) do not use the 4 psi rule to work out pressures as it is not reliable.

The 1 psi increase was for 4 tyres so I am not sure how it works if your van has 2 wheels. I would imagine the amount of weight that is supported by the draw bar would also come into the calculations.

Try ringing the technical inquiry number for Goodrich and see what they say.

Brian

Reply 3 of 5

FollowupID: 546948 Submitted: Saturday, Jan 19, 2008 at 08:59

Gronk posted:

The 4psi rule may not be the only method, but it's not a bad place to start !!!

You can increase the tyres all you like, but in the end the only way you know if they are right is if they aren't getting too hot ??

If someone told me to pump them up to 50psi, I wouldn't leave it at that without making sure the pressures stayed at a reasonable level ( and heat )

It's your 4x4 ( or van )-------don't take someones word as gospel

FollowUp 1 of 3

FollowupID: 546970 Submitted: Saturday, Jan 19, 2008 at 09:48

splits posted:

I am only repeating what the manufacturers of my tyres told me.

Everyone is free to do what they like with their tyres. I decided to ring the manufacturer of my tyres after a tyre service inflated my new tyres to a pressure way above what was recommended by the manufacturer of the car. When I questioned the pressures they looked surprised and suggested the factory pressures must be wrong.

I had noticed in the owner's handbook that two identicle size tyres, but with different load ratings, were listed as standard equipment. There were considerable differences in the recommended pressures.

The tyre service pressures did not comply with either recommendation so they left me with little confidence in them.

The tyre manufacturer's adviser must have had little to do the day I rang him because we spoke for about 15 minutes. This man even had his own 4b. It is amazing what you can learn about tyres when you speak to a tyre engineer who has been involved it tyre testing programes that included testing them to destruction out in the bush.

By the way can you tell me, in regard to tyre temperatures, how hot is too hot and how do you accurately measure it?

Brian

FollowUp 2 of 3

FollowupID: 547036 Submitted: Saturday, Jan 19, 2008 at 16:09

Gronk posted:

How hot is too hot ???? Don't know really, can only tell by years of getting a feel for the tyres at diff stages of a trip !!!

Thats why the 4psi rule is a good tool , it is the only one I can think of that lets you know what the tyres are doing....

If anyone else has got a better systemt to tell you in the real world what the tyres are doing then I,m all ears !!

FollowUp 3 of 3

AnswerID: 282484 Submitted: Saturday, Jan 19, 2008 at 11:20

Teago replied:

Tks to all who put in a response. I will now talk with Goodrich and let you know their response. Rgds Teago

Reply 4 of 5

AnswerID: 282585 Submitted: Saturday, Jan 19, 2008 at 20:58

Member - Charlie M (SA) replied:

Hi Teago
Only way for correct pressure is to weight the van on weighbridge and then tyre reputable store should be able to give you correct pressure for tyre out of ADR on Njoy book.
Cheers
Charlie

Member: My Profile

Reply 5 of 5

FollowupID: 547105 Submitted: Saturday, Jan 19, 2008 at 20:59

Member - Charlie M (SA) posted:

should be reputable tyre store
Charlie

Member: My Profile

FollowUp 1 of 1