That experiment means nothing. If you drove his truck you might have got the same mpg too. For example, his tyres might have been more worn than yours, that would change the mpg figures. Also dash figures are notoriously inaccurate
ROG:
Does the night heater affect fuel efficiency ?If not then why not run the AC from it ?
It will take the same amount of power to refrigerate the air capacity of the cab and that power can only ultimately be obtained from the same amount of diesel regardless of the method of refrigeration.
As for the saving in diesel from either closed windows or turned off air con if the margins are that tight then something is wrong anyway.In the case of the car I open the windows unless it’s cold and use the air con when it’s hot.Except in the case of the older classic which I’ve removed not because of any bs fuel cost issue.But because of all the aggro involved in maintaining it and lack of accessability to do most jobs with the compressor needing to be removed just to get at the spark plugs.
Reef:
ROG:
Does the night heater affect fuel efficiency ?If not then why not run the AC from it ?
And where do you think the night heater draws its fuel from?
I did not know so that’s why I asked
Does that mean using night heater gives the driver a worse fuel economy ?
ROG:
Reef:
ROG:
Does the night heater affect fuel efficiency ?If not then why not run the AC from it ?
And where do you think the night heater draws its fuel from?
I did not know so that’s why I asked
Does that mean using night heater gives the driver a worse fuel economy ?
Put it this way,
fill a tank up with diesel and you can drive for arguments sake say 400 miles, now refill it again but punch a small hole in the bottom of the tank and you obviously won’t still be able to do 400 miles on that same tank.
So no, a night heater will not affect the fuel economy of the engine but if you are using or losing that fuel elsewhere then you are still not going to achieve the same MPG 
ROG:
Reef:
ROG:
Does the night heater affect fuel efficiency ?If not then why not run the AC from it ?
And where do you think the night heater draws its fuel from?
I did not know so that’s why I asked
Does that mean using night heater gives the driver a worse fuel economy ?
It depends on the definition of ‘fuel economy’.If margins have reached the point where open windows or using the engine to provide heat or direct air con power,let alone free standing night heaters or air con pods,are being counted as part of that figure, then it’s probably reaching the point of why bother.
Reef:
ROG:
Reef:
ROG:
Does the night heater affect fuel efficiency ?If not then why not run the AC from it ?
And where do you think the night heater draws its fuel from?
I did not know so that’s why I asked
Does that mean using night heater gives the driver a worse fuel economy ?
Put it this way,
fill a tank up with diesel and you can drive for arguments sake say 400 miles, now refill it again but punch a small hole in the bottom of the tank and you obviously won’t still be able to do 400 miles on that same tank.
So no, a night heater will not affect the fuel economy of the engine but if you are using or losing that fuel elsewhere then you are still not going to achieve the same MPG
The only other possibility is a free standing heating and cooling system with a seperate red diesel fuel supply. 
Conor:
Tris:
The day they start moaning about fuel efficiency will be the day I look for another job. It’s a load of crap, I drive an automatic so theres very little I can do to alter anything bar cruising at 50.Completely disagree. On Friday night two of us did a night trunk to Lockerbie. Both in the same trucks, 64 plate DAF CF Euro 6 automatics, both pulling the same loads in the same trailers on the same routes setting off at the same time, both running on the limiter where possible. On the Eco driving thing fitted to those DAFS he gets sub 20% and I get 80%+.
Over a distance of 614km he used 223 litres of diesel and I used 185. So in a single night on a 383 mile run he used 38 litres or 8.3 gallons more than I did. That’s 40 gallons a week or 2000 gallons of diesel a year, roughly about £10,000 a year worth of fuel more than I would. And he saves maybe 2-3 minutes each way over me.
I averaged 9.4MPG including cutting through via twisty minor A roads from the A19 to Darlington via Northallerton due to the A1 closure, going over the A66 both ways loaded (return journey 42 tonnes) on a very windy night where “slow down high winds” signs were on the M6. He averaged 7.8MPG.
But its a load of crap and you can’t do anything about it because its an automatic you drive? Rubbish. Stop excusing the fact you can’t drive.
If each of your company’s drivers increased their fuel economy by just 1MPG you’d save £5000+ in fuel each year per truck, enough to give them the ability to offer you a reasonable wage rise.
Your whole argument falls flat on its face when you talk about both examples being identical. For a start both units aren’t identical; no two units are built to such precision to be identical - some come off the production line better than others from new just like with cars. Equally some trailers run better than others. And I’d be surprised if the tyres are all the same and are all identically worn.
Must try harder.
I can see what you are saying Tris and you are correct that they won’t be identical, knowing the milage of both vehicles will help,but two 64 plates probably built on the same day and delivered at the same time ,are going to be as close as you will get to being identical,all engines are tested before fitting and have to be within a certain parameter otherwise they won’t meet their specs …Obviously for a perfect test the trailers would have to be identical with the weights the same along with tyre pressures etc …But even if not identical would the fuel figures be so different ■■?And the driver does play a big part in it .Note I am not taking sides here ,It is just a question…Even with an auto, permanently on kickdown will have an effect of fuel,There are so many variables .Also on the night in question ,they weren’t driven for a comparison ,it was noted 1 did better than the other …I have taken a works van down south for training course and did the trip on 1 tank there and 1 tank back ,other lad drove like an idiot ,took 3 tanks,i know as I was in it as well,same van
ajt:
That experiment means nothing. If you drove his truck you might have got the same mpg too. For example, his tyres might have been more worn than yours, that would change the mpg figures. Also dash figures are notoriously inaccurate
I do drive his truck. We all drive each others because we get given what we get given on nights. Nobody has their own truck. Night after night after night doing Lockerbie on that route I use around 175-185 litres depending on my load up and the weather and that doesn’t matter which of the 30 or so units I take. The vehicles are the same age, most of the fleet is within a mileage range of 100,000 to 140,000km and as far as I’m aware they’re all still on their first set of tyres so wear is about the same although from experience of tacho calibrations I’ve sat in on the difference between new and almost illegal is a couple of percent on the odometer. And yes dash figures are notoriously inaccurate which is why I used fuel used and distance travelled to calculate MPG.
Absolutely none of what you’ve said would account for a 20% difference in fuel consumption. Grasping at straws.
Tris:
[
Your whole argument falls flat on its face when you talk about both examples being identical. For a start both units aren’t identical; no two units are built to such precision to be identical - some come off the production line better than others from new just like with cars. Equally some trailers run better than others. And I’d be surprised if the tyres are all the same and are all identically worn.Must try harder.
The difference in fuel consumption is 20%. You can’t excuse that away with anything you’ve just said. I’d give you 5% but not 20%.
However the thing you ignore is that the trucks are all fitted with DAF Ecodrive onboard monitoring which shows how efficient you’re driving in respect to braking and anticipation for braking. He’s getting sub 20% which absolutely nobody else in the fleet has managed, especially on nights. I’m getting 80%+. So he’s doing a lot of braking and harder than I am too.
The other thing I didn’t mention is the Microlise scores. He gets a G for acceleration and full throttle use. That’s as bad as it gets. In the drivers table overall he’s in the last half dozen out of 60 or so drivers.
So not only is he braking worse, he’s accelerating worse as well and as I said, all to save a couple of minutes over a couple of hundred miles.
So the claims that because its an automatic that you can’t do anything about it is a load of crap. Pretty much everything that applies to economic driving that saves the most fuel with a manual applies to an auto.
Conor:
Tris:
[
Your whole argument falls flat on its face when you talk about both examples being identical. For a start both units aren’t identical; no two units are built to such precision to be identical - some come off the production line better than others from new just like with cars. Equally some trailers run better than others. And I’d be surprised if the tyres are all the same and are all identically worn.Must try harder.
The difference in fuel consumption is 20%. You can’t excuse that away with anything you’ve just said.
I can, I just did. Try again nipper. So by your logic if you’d been in the other truck the consumption would have been reversed. Yeah riiight pmsl.
Conor:
Tris:
[
Your whole argument falls flat on its face when you talk about both examples being identical. For a start both units aren’t identical; no two units are built to such precision to be identical - some come off the production line better than others from new just like with cars. Equally some trailers run better than others. And I’d be surprised if the tyres are all the same and are all identically worn.Must try harder.
The difference in fuel consumption is 20%. You can’t excuse that away with anything you’ve just said. I’d give you 5% but not 20%.
However the thing you ignore is that the trucks are all fitted with DAF Ecodrive onboard monitoring which shows how efficient you’re driving in respect to braking and anticipation for braking. He’s getting sub 20% which absolutely nobody else in the fleet has managed, especially on nights. I’m getting 80%+. So he’s doing a lot of braking and harder than I am too.
The other thing I didn’t mention is the Microlise scores. He gets a G for acceleration and full throttle use. That’s as bad as it gets. In the drivers table overall he’s in the last half dozen out of 60 or so drivers.
So not only is he braking worse, he’s accelerating worse as well and as I said, all to save a couple of minutes over a couple of hundred miles.
So the claims that because its an automatic that you can’t do anything about it is a load of crap. Pretty much everything that applies to economic driving that saves the most fuel with a manual applies to an auto.
Even with that explanation I still don’t buy it. Automatics are essentially dodgems - you put your foot down and they go. Some go through the gears more smoothly than others. My current truck is a nightmare and revs up before changing so I tend to drive a lot in manual. My fuel consumption is going to be rubbish. The lad who had the truck before me was spoken to about his fuel consumption. It’s one of those things. I’ve reported it so nothing more I can do about it.
Your current truck I think you might have said elsewhere is a Scania, and it sounds like you don’t know to drive it…
LIBERTY_GUY:
With so much emphasis on fuel efficiency these days, with truck drivers being rewarded for achieving an extra 0.001mpg per gallon (irrespective of the nuisance to other road users), it got me to wondering why they don’t disconnect the air conditioning in trucks, or order without the option of air conditioning? I remember reading quite some time ago that air conditioning can take 25% off the mpg figures for a car, not quite sure what percentage it affects on trucks though?Was just curious if some of these fuel paranoid hauliers limit the use of air conditioning, where it is fitted?
for christ sake dont give them ideas…
Tris:
Conor:
Tris:
[
Your whole argument falls flat on its face when you talk about both examples being identical. For a start both units aren’t identical; no two units are built to such precision to be identical - some come off the production line better than others from new just like with cars. Equally some trailers run better than others. And I’d be surprised if the tyres are all the same and are all identically worn.Must try harder.
The difference in fuel consumption is 20%. You can’t excuse that away with anything you’ve just said. I’d give you 5% but not 20%.
However the thing you ignore is that the trucks are all fitted with DAF Ecodrive onboard monitoring which shows how efficient you’re driving in respect to braking and anticipation for braking. He’s getting sub 20% which absolutely nobody else in the fleet has managed, especially on nights. I’m getting 80%+. So he’s doing a lot of braking and harder than I am too.
The other thing I didn’t mention is the Microlise scores. He gets a G for acceleration and full throttle use. That’s as bad as it gets. In the drivers table overall he’s in the last half dozen out of 60 or so drivers.
So not only is he braking worse, he’s accelerating worse as well and as I said, all to save a couple of minutes over a couple of hundred miles.
So the claims that because its an automatic that you can’t do anything about it is a load of crap. Pretty much everything that applies to economic driving that saves the most fuel with a manual applies to an auto.
Even with that explanation I still don’t buy it. Automatics are essentially dodgems - you put your foot down and they go. Some go through the gears more smoothly than others. My current truck is a nightmare and revs up before changing so I tend to drive a lot in manual. My fuel consumption is going to be rubbish. The lad who had the truck before me was spoken to about his fuel consumption. It’s one of those things. I’ve reported it so nothing more I can do about it.
on slightly different note, why do some of Howdens drivers think they are soooo special,■■ whenever i worked there through the agency there was always a sense of your scum and cant do the job to our standard, FFS your still a wagon driver on a general haulage job that just happens to pay a bit better than the norm !!!.. when given the choice of job, howdens or stobarts doing tesco’s,? stobarts every time for me and i didn’t have to wear a stab jacket as at howdens…see eddie st finally got the job.
As our are all old trucks they don’t usually bother getting the ac regassed untill I asked to gert mine done as its wasn’t cooling properly (mimes the one of the oldest on the fleet) being and 56. At first they said no them I pointed out fuel consumption is increased, drivers tire more easily. Also there’s and increased risk of damage to hearing with wind noise. There now going to gas them up
Connor let me know when you get the 5000 payrise for your perfect driving and then i will start driving more economical