I always change gear early to optimise efficiency. In a diesel this seems to not be an issue at all 1,500 rpm for up shifting is easily capable and also cruising in 5th at a steady 30mph with an engine speed of around 1,150-1,200 rpm seems to save fuel considerably without getting too much lumps and bumps from a diesel engine. However having searching through a few forums i came across a few posts that actually upshifting too soon can strain your engine? Is this a fact or a myth? Only considerable difference i've seen to this is that the engine usually needs a good blow out after a certain amount of time whilst driving in this style (Clears all the sh*t which is seen coming out the back)

 

You are not doing the "cabbie" i.e. 5th gear at 25mph ?

If not and as long as you are not labouring the engine then you should be ok. Remember at least once a week to give it a damned good thrashing otherwise the turbo, egr, and dpf (if it has one will soot up.

The above is for a diesel.

Petrol engines live for revs so thrash it or buy a diesel.

 

haha love it but so true! I noticed when i had my JTD diesel powered Stilo that the EGR would clog up driving in this style and on a few occasions i had some dodgy looks when i put my foot down and all hell broke loose, but that got written off and i'm now happily chugging about in a mk1 turbo diesel mondeo which never really smokes upon a good thrashing...

 

You can tell if the engine is labouring from the noise and feel. When that happens you should change down.

 

Good for economy as said, so long as you avoid laboring the engine.

Martin

 

I do it and get a good mpg return but as said above it clogs shit up so I do give it a good boot now and then.

 

Find out where peak torque is and drive the car above that speed. Once upto speed cruise as close to peak torque as you can.
Changing up that early will destroy the DMF!

 

on our vivaro's there is a little light which tells you to shift up or down

this little light always comes on just as the engine is coming on song so i'm sure that vauxhall knew what they were doing when they installed the software for that little light

yeah, like fuck they did, we ignore it now as it never gave you any acceleration

on some it comes on later the more you boot it but it's always there at around 2500 rpm and sometimes as low as 1600 rpm

on a cruise it can give as good as 37 mpg on an empty motorway at 65 mph in 6th but generally around town or driving "normally" it is anywhere between 24 and 27 mpg (i know because i do the numbers for the fuel vs mileage costs for each driver and some are consistently as low as 22 mpg while some are normally hovering around the 28-9 mpg mark)

 

Ive noticed on diesels (espcially endura engines) the anti-stall comes on at about 1100 rpm, so you can be crusing in 5th at 30mph, drop to 28mph and the anti stall comes on a dumps shit loads of diesel into the engine which gives uncontrollable acceleration back up to about 33ish. At which point the live MPG gauge drops to about 11mpg from 80mpg.

I never really change gear above 1800rpm unless I need to and I always return a good 48MPG if I drive normally, just had a remap to and its gone up to 51MPG!

 

Peak torque = peak efficiency therfore try to drive at this RPM (not speed!) in each gear

Changing up too early will cause damage yes, you should be able to feel if the engine is labouring etc

 

Ive just finnished my CPC course for hgv driving & one of the courses was fuel economy. They actually encourage labouring an engine? Oersonally i think its BS that this helps economy as all that strain just creates wasted fuel. Changing gear that little bit later so the revs are still in a useable range is more fuel effective.

My fiesta 1.6 tdci will trundle along at 30 mph in 5th at about 1050-1100 rpm but any slower & it REALLY doesnt like it. Thos does help economy a lot & i even skip gears when accelerating onto a motorway, 1st to 3rd to 5th.

 

on a st170 peak torque is 5500rpm. id be bombing round like an idiot lol

 

"Sorry officer I was trying to save fuel"

 

As I recall it makes 85% of peak torque from 1850 rpm or something daft and also you don't have to bomb anywhere, rpm doesn't equal speed unless you don't have a gearbox

 

passiondriveyourfordlikeagranny.com

 

just having a laugh. lol not picking you up on it

 

My diesel Peugeot vans get reved until they stop climbing and I then change up. Well up until the hit the electronic limiter at a GPS verified.










52mph

 

my TDCi transit 2010 2.2 90PS (flat as a wiches tit with 2.5tonnes in weight)

has an economy light (green arrow) in 1st,2nd,3rd and 4th

indicating to change up at part throttle about 2500rpm, revs usually drop to about 1300rpm

early diesels like yours dont have fueling backed off low down like a TDCI engine,
you dont use more fuel at part throttle revving to 2-2500rpm than you would giving it 3/4 throttle, if that makes sense

more power = less squirt

change fuel filter, do an injector leak off volume test to see if the nozzles are blocked.

use good quality fuel, keep to about 1/2 tank and economy will be optimum