Best speed to drive on motorway?

We have a 2006 Defender 90 TD5

I just had to drive to mid Wales and back, and I admit I pushed it a bit, sitting at 75mph on the motorway.

I was a bit shocked when we got back to find that we'd used £60 of diesel to do 220 miles....that's about 22mpg

There's a bit left but only maybe another 10 miles worth, so maybe 23mpg

Is this about right when driving it at these speeds?

I'm guessing that 75mph is not the best speed to drive at in the Defender! I will be doing 65mph in future.

With the aerodynamics of a brick its not a surprising mpg at that speed!

I do between 60-65mph on longer runs and it doesnt seem to effect my mpg too much.

50 mph in the slow lane.

Sorry, is this a question for best speed for best mpg or safest speed?

I run mine at 65mph on motorway. Checked speed with GPS as speedo is inaccurate with big typres on. Does 30mpg at 65mph with about 9 psi boost. Engine tuned a little but great for fuel ecenomy

Qplater said:

I run mine at 65mph on motorway. Checked speed with GPS as speedo is inaccurate with big typres on. Does 30mpg at 65mph with about 9 psi boost. Engine tuned a little but great for fuel ecenomy

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Same here. Same set up as well.

It's about the right speed to help prevent bleeding ears from the noise as well!

get this.
the series 3 does 35MPG at 65. about 32MPG at 75

i choose the 32MPG usually.


and no the door tops dont want to flap

get this.
the series 3 does 35MPG at 65. about 32MPG at 75

i choose the 32MPG usually.

Are you sure! Dodgy speedo? wishful thinking?

speedo does read out by quite a bit. but i know what speed im doing.

bearing in mind it has an overdrive, RRC diffs and 7.50 tyres. and a tuned TDI (the tuning did actually improve my MPG by more than youd expect.

foot to the floor.

1spin said:

foot to the floor.

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I was about to write these very words...scary.

Our Defender will do over 90mph flat out. I tried it once and got to 90 and it was still wanting to go a bit faster.
Obviously this is not the way to drive the vehicle. My wife drives at about 60 on the motorway and I think I'll peg it at 65 if it gives me an extra 50 miles from a tank.

If I am feeling really skint, which is pretty much all the time nowadays, I save fuel on a longish haul by sitting behind the big lorries. Boring, but it saves you fuel..
If I am feeling a bit flush, I go all out and sit behind a coach..

Its amazing how much money you can save if you have to..

1spin said:

foot to the floor.

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on the autobahn got to 103 in it when it had the 235/70's on.

it wasnt that scary to be honest but i wont be doing it too often. i like to stick to under 80 else the wind gets a bit noisy.

I keep my TD5 90 at 60mph. It has a had a remap but i find i get about 30mpg i have 285/75/16's on aswell. the speedo reads 55 when im doing 60.

I drove on the motorway once,never again

BIG_GINGA_BEARD said:

I keep my TD5 90 at 60mph. It has a had a remap but i find i get about 30mpg i have 285/75/16's on aswell. the speedo reads 55 when im doing 60.

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Thats all it will do, as there is a big load in the right front and exceeds the GVW

Now you know one of the reasons why those big trucks have them speed limit stickers stuck on their back ,The'r not only safety reasons

Every Landy is different, so you need a bit of mechanical sympathy with the vehicle to tell what speed it's comfortable at. Mine will do 80 with the wind in the right direction, but it's hard work for the old girl, and I find cruising at about 60-70 is comfortable for both me and the car. Fuel economy is a bit less than normal use - maybe 22-23 as opposed to the usual 27-28.

I find it quite relaxing these days to plod along in Lane 1 at 60-odd, enjoying the scenery and eating my pack lunch. After all, if I wanted to go fast, I'd be driving the Lotus.

Is your Lotus Elan the classic one or the new version?

Here's my Lotus! Different driving experience to the Defender....but they are both great fun.