Fuel economy when towing

[Mark from Brisbane]

Yes, def lighter mine which is 2150 Tare and 2560 ATM (although I can only carry 2500).

I don't carry much in the van, limited food (mainly what's in the fridge), limited cutlery / crockery and very limited clothes...spares reside in the drawers of the Prado.

Over the weighbridge, full of water (190 Litres) we came in at 2460......I few bits and pieces get added in (mostly food) as we go along but still under the max allowed.

I should add (apart from the fuel) its a dream to tow....only struggles on steep hills, and starting from a dead stop on a steep hill.

Very happy really although was hoping for 15 litres per 100 rather than 17, BUT, not the end of the world.

[sj_001]

Also, not sure if relevant, however I generally run 95 at home, and the 91 was being used in part due to availability but mostly because it's alot more expensive. The 14l/100 I got was from a second fill of 98, I can't recall the fuel consumption on the first tank of 98 after using 91, but it definitely took atleast 1 full tank to notice any major differences.

The JAYCO is definitely lighter than your lotus, figures are:

Tare 1332
Gtm 1490
ATM 1632

Cheers

[MadJak]

A good friend of mine also pointed out that with unleaded, 91 / 95 / 98 is the octane rating. Octane stops pre ignition (pinging) on high compression and doesn't necessarily mean there is a higher energy content to the fuel, although it can too. The ECU in your car will advance the timing over time if you run higher octane fuel however this may take a while to kick in ie several tanks of fuel.

So generally, running on 91 octane and filling with 98 for one tank will result in no immediate net performance benefit. Always running your car on 98 may give you some extra power due to the auto timing advance on the ECU, but one tank of 91 will drop it back.

Edit: If you want to test running 98 whilst towing, my suggestion is to run a few tanks of 98 around town first before starting your trip otherwise you may not see much benefit. I figured it wasn't worth it for my trip as I wouldn't be able to get 98 or even 95 everywhere.

[MadJak]

This is for a Petrol:

I just did a 8000km trip to the Kimberly towing a camper. I also had a 350mm high rooftop bag and both car and camper where all very loaded up. Ran unleaded 91 the majority of the trip due to availability and averaged 20.5L/100km on 265/70 tyres. So factor that down 5% and it would be around 19.5/100km for the trip. That included a lot of tarmac @ 110kph with a lot of driving against a small headwind, as well as towing on The Gibb River Rd (60-90kph) and various 4x4 tracks without the camper.

I jacked up the tyre pressure for highway driving and ran 26ish offroad on both car and camper. Into the headwinds I could use up to 23-24L. Slowing down to 90ish would see my figures drop between 2-4L/100.

I drove a short distance when I got back without the rooftop bag and I think it would have accounted for 2L/100 by itself though maybe it's the smoother roads around Perth having less friction.

From my usage, I think 17-18 is possible with a petrol if very conservative up hills and overtaking and maintaining around 90Kph which is the sweet spot for towing in S4.

[Mark from Brisbane]

Interesting , there's another 17/100 albeit Diesel v Petrol, I would hesitate a guess that a Swan even with 2 kids extra wouldn't weigh anything like my Lotus.

I'm going to invest in a Scangaugue next , who knows I might even beg to to tow at 100Kph and not chew nah more diesel!!

[bdee]

Hi All, 1st Post for me, hoping it comes through okay!

2008 Prado
V6 Auto
100K
265 70 17 Mickey T's

I thought I would share fuel figures from a recent ~6500KM trip from Sydney to The Daintree over a 3 week period (not really long enough, but that's another story!) towing a 2012 Jayco Swan Outback with 2 Adults and 2 Kids, 2 Ice Boxes, Food Clothes etc.

I used both 91 Unleaded and 98. The numbers were dramatically different. Some routes below;

- Cairns to Cape Tribulation towing Van, plus day trip (without van) up Bloomfield to the Lions Den and return to Cape Trib plus some driving around to the local tourist spots then towing back to Cairns after 4 Days - Average Fuel 20 L/100 - UNLEADED 91 (Various Speeds)

- Cairns to Airlie Beach towing Van - All Bitumen, still approx 20 L/100 - UNLEADED 91 (Speeds generally between 95 and 105)

- Gympie to Hastings Point - 14 L/100, - UNLEADED 98 (Speeds 90 - 95)

- Hastings Point to Sydney - 16L 100, - UNLEADED 98 (a few more hills on this run, but still not too bad)

I was hoping for a low fuel usage with the combo of slower driving and perhaps better roads and 98 Unleaded, but a low of 14 was unexpected.

Overall, the total trip achieved 17.3 L/100. All in all, I thought 17s aren't too bad, but next time I will be trying to consistently use the 98 if available.

Cheers

Interesting I will run the next tank on premium and see if it helps?

Brett

[sj_001]

Hi All, 1st Post for me, hoping it comes through okay!

2008 Prado
V6 Auto
100K
265 70 17 Mickey T's

I thought I would share fuel figures from a recent ~6500KM trip from Sydney to The Daintree over a 3 week period (not really long enough, but that's another story!) towing a 2012 Jayco Swan Outback with 2 Adults and 2 Kids, 2 Ice Boxes, Food Clothes etc.

I used both 91 Unleaded and 98. The numbers were dramatically different. Some routes below;

- Cairns to Cape Tribulation towing Van, plus day trip (without van) up Bloomfield to the Lions Den and return to Cape Trib plus some driving around to the local tourist spots then towing back to Cairns after 4 Days - Average Fuel 20 L/100 - UNLEADED 91 (Various Speeds)

- Cairns to Airlie Beach towing Van - All Bitumen, still approx 20 L/100 - UNLEADED 91 (Speeds generally between 95 and 105)

- Gympie to Hastings Point - 14 L/100, - UNLEADED 98 (Speeds 90 - 95)

- Hastings Point to Sydney - 16L 100, - UNLEADED 98 (a few more hills on this run, but still not too bad)

I was hoping for a low fuel usage with the combo of slower driving and perhaps better roads and 98 Unleaded, but a low of 14 was unexpected.

Overall, the total trip achieved 17.3 L/100. All in all, I thought 17s aren't too bad, but next time I will be trying to consistently use the 98 if available.

Cheers

[AJ120]

Well for where I ( we both) go that answers the question, reliability please!!!

Yep, Potato chips are the only ones coming near my rig!

Cheers Andrew

[Mark from Brisbane]

If a chip is going to give you more power and better fuel economy there has to be a trade off, otherwise Toyota would run the same tune especially if the fuel savings were in the 15-20% range.

That trade off has to be reliability, that's a big trade off in a modern CRD Diesel.

Cheers Andrew

Well for where I ( we both) go that answers the question, reliability please!!!

[bdee]

Thats actually not to bad, especially considering the general assumption that the petrol version will drink like a fish and therefore should not be considered for such duties. I dare say you take it very easy and drive to conserve fuel.

Its funny how the Prado built their reputation mainly on their Petrol engine yet in the 150 series it has become irrelevant. Whilst I have not towed with the diesel I spent a lot of time driving both a Petrol and Diesel version and the Petrol drives so much better for around town. For what I am doing the Petrol seems just fine and probably uses about 20% more juice. As for how I drive I would say I average about 90kph so yes I do drive conservatively.

Brett

[bdee]

Exactly...

I have been using either E10 or regular 95 unleaded when out on longer trips ( much cheaper out west ), but will be giving just the higher 98 premium unleaded a run when towing on longer hauls.
Have been using it around town but does not seem to effect fuel economy to a great extent when plodding around in the potholes of Sydney metro.

91 for me I have not seen a benefit in fuel consumption using the high octane.

[AJ120]

If a chip is going to give you more power and better fuel economy there has to be a trade off, otherwise Toyota would run the same tune especially if the fuel savings were in the 15-20% range.

That trade off has to be reliability, that's a big trade off in a modern CRD Diesel.

Cheers Andrew

[barajak]

I forgot before to ask this question, would there be a significant benefit to install a chip???

I know it would give me more power ( and that would be nice up a steep hill), but for most of the time the existing power does pretty well.

Next year I'll be away for 6-7 months and plan on doing between 20-25 k , so a 15-20% saving ( and I have my doubts on those figures) could save a few dollars.

So,

Does anyone use one, that tows something similar in weight to me and if so how's your fuel consumption going??

I should let those with a chip say something first but lets not. The chip manufactures claim better power and they do this with controlled over-fueling, mainly at low and medium revs and mainly at medium to heavy throttle positions and from what I have read they mostly settle with genuine settings for cruising as this is the most economical. Makes it hard to see where fuel savings could come from other than drivers imagination. This forum has more than a fair share of problems discussed caused by chips so, because like you, I think the power output is fine for every day driving, I will settle for a little slower off the mark with a load and go without a chip.

[Mark from Brisbane]

I forgot before to ask this question, would there be a significant benefit to install a chip???

I know it would give me more power ( and that would be nice up a steep hill), but for most of the time the existing power does pretty well.

Next year I'll be away for 6-7 months and plan on doing between 20-25 k , so a 15-20% saving ( and I have my doubts on those figures) could save a few dollars.

So,

Does anyone use one, that tows something similar in weight to me and if so how's your fuel consumption going??

[Mark from Brisbane]

I think the weight I was carrying ( extra ) has made a big difference....I had nothing extra in the van, weighed it full of water , with food in and limited clothes and I was just under the 2500Kg.

When I first towed it, the Prado was relatively empty....on the recent trip I pulled out the back seat and added a basic camping kit, spares, and of course the extra food, generator, spare booze.

Also on this trip I kept the spares in a space case on the roof rack, whereas the first trip didn't bother with the spares as all I did is go down to Sydney and back, via the Pacific and New England Highways.

So bottom line ( for me) is all that increased the average from 15 to 17.

In relation to the quotes on the 200 series, that wasn't just from one owner, I spoke to many and of they were towing 3000Kg plus ( and most were) they were all getting about the 22 per 100 as an average .

I saw a guy towing a Kimberley Caravan ( I think about 2100 fully loaded) a and he said he was getting 19 travelling at 105Kph

Don't know what the Jeeps were getting , but holy dooly there are some of them towing vans these days, I'd say Toyota must be crapping themselves.