Fuel Economy

Years back you used to be able to buy an aerofoil/spoiler thing to fit the roof of your tow car that was supposed to improve aerodynamics when towing .... the fact they don't sell them anymore might suggest that they didn't work very well .... though HGVs still have something similar on the roof of the tractor unit 🤷‍♂️

37mpg when towing!? I can't get that solo in my towcar 🙄😉

You'll have to let us know how you got on. 🙂

North Devon and the Westcountry in general are probably the worst areas for fuel economy so don’t expect miracles. Go to Norfolk instead😀

Like ED, I consider 37mpg towing to be brilliant. Our Shogun gave 16 towing and about 28 solo.

With our Sorrento it's about 25 to 29 mpg towing.

(Of course to make it a fair test you'll have to have the roof box empty)

At 37mpg you are doing well. I expect a minimum 34/36 mpg but on a good long motorway run return 40mpg. I averaged this figure in Holland last summer and then when towing from Merseyside to mid Devon when we moved down last Sept. I have a 1.5 petrol Audi manual but tow a wind defeating pop top Eriba at 1200kg.

Colin

Caravans are about as aerodynamically imperfect as you can get. They don't lend themselves to much improvement whatever you do to them or to the towing vehicle so don't expect miracles. The overall frontal area of your outfit doesn't change one bit if you have a roof box or not.

Caravans and good aerodynamic performance simply don't mix very well. As the aerodynamic drag increases with the square of the speed one might get some improvement on a long and relatively fast run, but nothing in slow heavy traffic.

Maybe the Mercedes F1 team should try a roofbox , it might help with the aero performance 

Useful thoughts, thanks to all. Yes I will let you know how the trip goes.

Out of interest, the Astra is a 165bhp 2.0L tdci manual. I'm not what you would call a slow driver, but I drive with fuel economy in mind and generally within the max speed limits. As an example, I regularly drive from North Essex to Bedford to support my single parent son, looking after my grandson etc. I have done the 110 mile journey in under 1hr. Two weeks ago, I decided to easy as I had time and set cruise control at 60mph sometimes 65mph. The run was pretty clear other than speed restriction on a section of the A14. I have a picture (taking when it was safe to do so!) showing 63mpg on the display. A lot of vehicles can give better mpg if driven in the correct engine's power range, particularly when moving from stationary etc.

Anyway, as we know, towing is a different matter. Think my 2 year old Cockapoo will have to pull part of the way! Regards to all.

David.

110 miles in less than an hour! That’s not something I would be proud of🤨

As we all know we cannot beat the laws of physics, but we can also use them. If you look at the power output specification of most cars you will note peak torque is usually around 1,900rpm. At this point the engine is working at it's most efficient and also happily for us when we have a van on the back is at the sweet point for if we need it. If you drive at these revs I strongly expect you will see 55mph on your speedo.

Colin

There is no substitute for horsepower and design for intended use. My Navara 3L V6 would return around 30mpg when towing my Valencia. Set the cruise control and it wouldn’t deviate from the set speed. It’s replacement discover sport 2L has been returning 24- 28 mpg towing the same caravan and you have to override the throttle on hills or it loses speed. - that said, solo and around town, the discovery is a lot sweeter on the wallet