Best economy

[williampp]

Would like to hear some views on what is the best gear & revs to tow a caravan.

We have a 100 series Landcruiser, towing a 2.3 ton Phoenix. I do not use overdrive, and tow at about 2200 revs (which is where it develops max torque) which gives me about 80 K's/hour

[rdog]

Bill I worked for cummins engine company ( truck engine area) for 30 years before i retired & tow a
supreme caravan about 2 tonn with a mitsu pajero 3.2 ltr diesel , mostly tow in 4th gear ( direct drive)
at about 2300 rpm(max torque at 2000rpm ) at about 90 kph get 15.5 ltr per 100km fuel consumpion.
I think you are spot no with your approach.

[williampp]

Thanks Rdog,
Our Landcruiser uses 12.9 ltr per 100 K, not towing (taken from Longreach to Rockhampton) and 17 ltr per 100 K towing (taken from Longreach, Winton, Boulia, Alice Springs). Our van is 2.2 ton on the vin plate, probably 2.6 with our gear in & water full. I am pleased with the 17 ltr's but I am always open to ways to improve it.
Any comments on tyre pressure, have heard that high (within reason) pressure helps economy.

[Jim Carroll]

I was told off recently for not having enough tyre pressure about 35psi in our trailer about 2.5 tonne loaded.

Now run 45-50psi . Since then only short runs so it will be interesting soon as we head of to canberra about 9hr drive, Hopefully will make a difference

[rdog]

Bill i run light truck rated tyres these are fairly stiff in side wall compared to passenger rated ones
run 40 psi when towing & 60 psi in same tyres on van.
Agressive tread and deep tread tyres increase rolling resistance ( take more power to drive) and will increase fuel burn.

[les88]

In a 4wd magazine there was an article on van tyre pressures. I used the formula to get the correct pressure for my van.
The tyre has to stay in a margin of 4psi
With van fully loaded and the tyres cold select a starting off pressure of "say' 40psi.
Drive until the tyres are hot check pressure. If pressure has risen to 50psi, when the tyres are cold add 5psi. You keep adjusting and checking until you are in the 4psi increase margin.
The formula works the same with the towing vehicle I had a diesel Toyota tray back ute and with the load that I was carrying the rear tyres needed 62psi. :2tsup::2tsup:
les

[williampp]

Thanks Jim, rdog, les88, I normally run the Toyota while towing the van at 32 psi front 40 back. Van at 42. I like that formula les, will give it a try next time we are towing.

[RETIRED]

I agree with Les.

When I drove a Landcruiser tray the tyres were at 65 PSI in the back.

[dazzler]

Hi bill

I would recommemd fitting one of these;

http://www.scangauge.com/

They give immediate outputs so you can see whats going on. I made a number of 800km trips over a two week period in my Rav4 and used different grades of fuel and found that 95RON fuel sitting on 110 gave the best economy in my vehicle. We are about to head off on a 3month holiday and will be fitting one of these to monitor everything.

[williampp]

Hi Dazzler, I have checked that Scangauge, it looks like a great buy, would give one info that is only available on more expensive vehicles. It does not work on our 2002 100 series Landcruiser, it would be in the post if it did.