My Ranger 28.03 mpg today - a personal best and down to the hot weather and driving very slowly carefully.
, don't understand this, also sherwood cleaning from the 1st page suggested the same thing.
Hot weather, and heat in general makes an engine less efficient, not more. The reason being, cold air is denser, so more can be sucked in per combustion, which means the engine produces more power, which in turn means you don't have to use so much throttle for the same result.
Yes and no.
On a normal car yes. My Capri goes better in the Autumn in cooler, more dense air. In the case of my truck, which is geared down considerably so use of more or less throttle is irrelevant as is speed, it comes down to ambient operating temperature as Lee says. It means it's up to temperature much quicker, doesn't cool down as much between jobs, you're not running any heating or using any headlights but mostly the engine oil, gearbox oil, transfer box oil and diff oil remain much more fluid and reduce friction. It's small stuff but with an mpg like mine it's becomes very noticeable.
I've just put the accounts in on Friday and completed my actual fuel record for the year:
I had a worse mpg of 24.41 in December and a best of 28.03 in June / July.
Same mileage, same jobs, same load, same driver, same style (slow!), different temperatures.
A couple of years back my parents went up to Northern Scotland in June in their 406 hdi and at 3c the mpg was around 48-52 with my dad's usual ambling. After three days the temperature jumped to 25c and the mpg into the low 60's.
