Camper Tyre Pressure

[Steffo1]

Our camper, fully loaded, sits around the 1000kg mark. I've been running 38 PSI in the tyres on the blacktop but a bloke in my local refreshment establishment reckons I should be running 45 PSI. 
Yes/No?
All advice appreciated.
( I did a search under the subject title & got zilch)

[DannyG]

You forgot to mention the size and type of tyre your using.

I use BFG all terrains, 265/70/16 and I run 40 psi on the black top, same on my Patrol it has BFG muddies 285/75/16. Its probably a touch too much but it makes a difference to economy

Of course they all go down to around 25 psi when we are doing long runs on gravel roads.

[KingBilly]

My Customline's recommended tyre pressure is 235kpa or 34psi.  Never weighed it but it is rated to 1600gs.  Done about 6000kms and no sign of wear.

KB

[stephwoodall]

I have a Customline too.  I generally keep the pressures a couple of psi below the tug.  I've never had any probs.  Have done about 25k on the current tyres with no signs of wear.  I usually have about 40psi on the black top for the tug.

When on sand though (was at Fraser Island recently) I had 18 in the tug front and 20 in the rear with 18 on the camper.  My logic was that with the extra weight on the rear of the car the tyres dimensions would be similar. 

Don't know if I am over thinking it but it makes sense to me.

Cheers

Stephen

[GraemeL]

I have Mickey Thompson ATZ 265/75R16 manufacturer recommends 38psi on black top.

[SteveandViv]

I tend to follow the rear car pressure. I will run 38psi around Broome, 28psi when doing a run to Cape Leveque and 20psi for longer low rang runs and for sand like the Simpson I ran 16psi.

[muzza01]

Here are a couple of other opinions if it helps:
http://www.myswag.org/index.php?topic=27971.msg435503#msg435503
http://www.myswag.org/index.php?topic=12922.msg192463#msg192463
http://www.myswag.org/index.php?topic=19338.msg350830#msg350830
http://www.myswag.org/index.php?topic=7624.msg121291#msg121291

[GeeTee]

Our camper, fully loaded, sits around the 1000kg mark. I've been running 38 PSI in the tyres on the blacktop but a bloke in my local refreshment establishment reckons I should be running 45 PSI. 
Yes/No?
All advice appreciated.
( I did a search under the subject title & got zilch)

lol.. 'refreshment establishment'!
Higher trailer (and tow tug, too) pressures will lessen drag and aid economy by a few percent. Assuming your trailer suspension has some compliance and doesn't shake your equipment to bits, give it a go.. but the difference between 38 and 45 is largely academic on a trailer as there are no drive and very little braking/cornering forces to contend with compared to the, say, fronts on an AWD vehicle.

Dump to 25 when touring on gravel... that's what I do, anyway

Hope this helps

[dungee]

For driving on roads apply the 4psi rule, sand, soft surfaces and low speeds can allow for a lower pressure. 

[TOPNDR]

AOR recommends 33psi (cold) in their Quantum (2200kg -2400kg ATM) tyres, and the Q has independent coil suspension, with dual shocks per trailing arm.  This pressure is recommended, as I understand, to lessen road vibration transmission through to the chassis and other components.  I've gone as low as 21 or 23 psi on bad corrugations but never more than 35.

Whilst high tyre pressures might reduce rolling resistance by a smidgen, and thus fuel consumption. Nothing comes for free.  The price one pays is a harsher ride, with the tyres less able to absorb as much of the road undulations and roughness, as if they're at a lower pressure and better able to flex.

[Steffo1]

Thanks for the advice. I might try running around the 33 PSI now although some bitumen roads in Qld are worse than a gravel road. As a side, I've never had them below 25 PSI off road but haven't had it in soft sand either!

[GeeTee]

AOR recommends 33psi (cold) in their Quantum (2200kg -2400kg ATM) tyres, and the Q has independent coil suspension, with dual shocks per trailing arm.  This pressure is recommended, as I understand, to lessen road vibration transmission through to the chassis and other components.  I've gone as low as 21 or 23 psi on bad corrugations but never more than 35.

Whilst high tyre pressures might reduce rolling resistance by a smidgen, and thus fuel consumption. Nothing comes for free.  The price one pays is a harsher ride, with the tyres less able to absorb as much of the road undulations and roughness, as if they're at a lower pressure and better able to flex.

that's why you drop pressures on the rough stuff... but like your car, you shouldn't have to do it on smooth 

[briann532]

3 to 4 psi rule works for me.

Each tyre on each car with each load makes it different.....

Gotta love TPMS.

[GeeTee]

3 to 4 psi rule works for me.

Each tyre on each car with each load makes it different.....

Gotta love TPMS.

How does that work on gravel or sand, Brian?

[briann532]

Don't do the test on gravel or dirt........
Test it on the blacktop as in the original question.
This gives you your best road pressure to work off as a base.

Then accept the fact that when you drop the pressure on sand or dirt, (which I don't do, but that's an argument for the electrical section only!!!) the tyre walls will flex more and build up more heat and pressure.

I think the question was to find the best tyre pressure for on road.
Off road is a different ball game and a lot of factors need to be considered.

Brian

[TOPNDR]

How does that work on gravel or sand, Brian?

I've found it works ok on gravel and sand. 

I decide upon a speed limit given the tyre pressure, more an educated guess than a science, and don't exceed that limit.  In my experience thus far, I've found I can fairly reliably start with a cold pressure and have it raise by 4ish psi after an hour's driving.  The faster the speed I'm going to drive, the higher the cold pressure.  And the rougher the road and thus lower I want the cold pressure, the slower I drive.

[gronk]

I've found it works ok on gravel and sand. 

I decide upon a speed limit given the tyre pressure, more an educated guess than a science, and don't exceed that limit.  In my experience thus far, I've found I can fairly reliably start with a cold pressure and have it raise by 4ish psi after an hour's driving.  The faster the speed I'm going to drive, the higher the cold pressure.  And the rougher the road and thus lower I want the cold pressure, the slower I drive.

And while a lot of this stuff is guesswork, the above is a very sensible reply to something that doesn't need to be rocket science ...

I had a tyre failure once along Cordillo Downs track because at the start of it I dropped pressures down to 28 psi, which seems all good, except that further along, the track was in good condition, and speeds increased to approx. 90 ( and sometimes more )........and with the load from a camper, the rear tyre decided to overheat and blow......the other tyre that didn't blow was VERY hot to touch !!

So, now I only lower pressures when I'm sure the speeds are going to be low enough for this sort of thing to not happen.....as an example......when going from Yunta to Arkaroola, I lowered pressures to 28 psi, but set the cruise for 70 k/ph.

[SteveandViv]

Exactly Gronk. We had a work car tyre blow out up the Gibb. While the pressure I was running was fine for our car it was not for that car. The tyre went over the bonnet, the rim was still to hot to lift after 20 minutes. It was just before the wet and stinking hot.