Do most drivers only use 5th/6th gear for higher speeds?. On my past cars (5 speed box) at 30mph I would be in 5th once I was no longer accelerating, and on my i30 petrol which had a 6 speed box i would be in 6th gear at 30 as engine would still be doing at least 1400rpm. By making use of top gear I do usually get close to the manufacturers claimed mpg. The reason I ask is on another thread some are suggesting even 4th gear is to high at 30 around town.

Edited 2 January, 20179 yr by POWYSWALES

Depends on the ratios. I can be in 6th at 35 in the car, but I need to be at 40 really to be in 5th in the van without labouring it.

I remember way back in the 70s OPEC oil crisis, Porsche did research that showed that 2000rpm was an ideal engine speed for economy.......they were a 'short stroke' engine though.

Nowadays engines are long stroke for better emissions and designed to achieve max economy and that engine speed is probably nearer 1500 (similar piston travel per thousand rpm) which is why the current trend to 8-10 speed gearboxes and programming to select and stay in the highest gear possible and also why there is commonly a 'sports' mode that can overcome the economy priority if that is what floats the boat.

I doubt if any auto journalists are interested in anything other than sports mode though.

Economy/emissions are the priority for engineers though.

Edited 2 January, 20179 yr by Ryeman

I read in here somewhere that the IAM recommended 3rd in town not for economy but for control of the car.

 

But I think it depends on the car. My VRS could drive in 6th at 30 when warm but my current Mazda can't cope with anything higher than 4th. 

As @Aspman says. Personal accounts include driving a Vauxhall Coarser (sic) Demerit (look, the badges on the back read left to right "D%20Merit") that would not take anything higher than 3rd gear at 30mph, and needed to be going over 50 before 5th was usable.

My Octavia would pootle at 29mph on level ground in 5th (5speed ALH) on tickover. Got a chance to reset the trip and the average over a continuous 1mile like that was an indicated 99.9mpg. Doesnt feel nice doing it though.

The Insignia is 4th (6speed) at a push at 30... again it just feels wrong doing anything higher.

Swmbo citigo is 4th at 30when she drives, 3rd/4th when i borrow depending on the ground. The car feels alot happier when its being revved higher.

Fab and t5 are both 4th in town. 5th n the revs are too low n its just not right.

Bike is happy in 6th at 25mph up a hill, open up and itll still pull well, but then i still use 4th most the time, otherwise its a pain getting right down the box again for a standstill.

My Octavia (manual, 6 speed) was OK at 30 MPH on the summer tyres - with indicated RPM at just over the point where the turbo starts coming on boost, but with the winters, 6th is just a little too tall in a built-up area due to these having a slightly larger rolling radius.   

I find the less input on the accelerator pedal in order to maintain a speed gives me the best mpg more or less regardless of engine speed. Highest gear at low speed is economical to a point (where on straight, flat, slight decline or in a lab), but any acceleration or input to maintain speed being laboured requires more fuel than being at or closer to peak torque in a lower gear for general speed maintenance and of course heavier on clutch/DMF etc. As in only needing to use 3-5% throttle in 4th may be better than using 10-15% in 5th to maintain a lower speed. 

Re the OP, you have a DSG and all you need to do is put it in 'D' and drive and the gears are chosen and you can coast sometimes.

 

The Manufacturers do not 'Claim' any MPG for your vehicle unless you are 60 kg, drive with a less than full tank, no options and 

inside a temperature controlled building on a computerised cycle going no place and with no relationship to the real world.

http://skoda.co.uk/pages/fuel-consumption-statement.aspx

Depends on the car and the traffic.

 

My first 330d wasn't happy in top until as 50mph as it grumbled a lot, so that stayed in 2nd or 3rd around town. The current one can cope with higher gears at low speeds better, but it's still happiest in 4th or below. My e30 can be happily left in 2nd all the time from pull away to 30, or quite happily trundle along in 5th from 25mph upwards with relevantly decent acceleration once warm (e30 in 5th @30 on a par with parent's 1.6 focus in 3rd @30, I'd guess). My sister's Mini One (2010, R56) is too slow to go into 5th/6th at town speeds (despite the stupid gearshift constantly telling you to upshift), as is my parent's Focus.

 

In town, with traffic and obstacles, I opt for 3rd usually in most cars, but if it's clear or out of town, but still a 30, I tend to shift up to whatever the car is happy with. 

Edited 2 January, 20179 yr by TriggerFish

I read in here somewhere that the IAM recommended 3rd in town not for economy but for control of the car.

 

I've not read it in here but that was how I was taught to drive by my old man (a now retired Police response driver).

 

3rd at 30 gives you the option of easy acceleration if needed but more importantly significant engine braking from the instant you remove your foot from the accelerator in an emergency (i.e. you are already starting to slow down before you hit the brakes).

Pollution controls seem to have made engine braking less effective from my perspective compared to the old cars.

Pollution controls seem to have made engine braking less effective from my perspective compared to the old cars.

I'd agree with that, it feels more like coasting with a manual GB than it used to be way back when, which, of course it is unless it has initiated re-generative braking. 

Pollution controls seem to have made engine braking less effective from my perspective compared to the old cars.

 

 

I'd agree with that, it feels more like coasting with a manual GB than it used to be way back when, which, of course it is unless it has initiated re-generative braking. 

Well my 2002 TDi has little enough engine braking that I can have to brake to hold station behind vehicles that have just closed throttle, so I suspect that "free running" may also be part of it.

I remember in older engines there were HC peaks when the throttle was snapped shut during manual up-changes in particular, but now I'm not sure if that applies to the modern engine with fuel cutoff.

I read in here somewhere that the IAM recommended 3rd in town not for economy but for control of the car.

 

This was one piece of advice I listened to on my Speed Awareness Course - use 3rd gear as your "driving" gear around town in 20 or 30 mph limited zones, and 2nd as your "hazard" gear and you'll find in almost impossible to speed.   The increase in fuel burn is negligible, but keeping the car under control is much easier.

The funny thing is, since following this advice, I haven't been nabbed by a single camera!   :D