I have an 06 MCS with a Manual but I don't have the milage calculating computer thingy (or a fuel pressure gauge)...

I learned to drive in an old beetle (4spd) so I'm not really sure I know how to use all these gears.

A co-worker with a BMW 3-series was just telling me 6th is only for highway speeds but that's a much different car & trany... It never occurred to me to drive down the road at a steady speed in 5th instead of 6th. I've always used 1st - 5th mainly to get up to speed not to maintain a road speed.

Am I hurting my car or at least my fuel economy driving at say 35mph in 6th?

 

I'd say that is pretty unnatural, I usually cruise at 35mph in 3rd at about 3k rpm, I would imagine cruising at that in 6th is practically no acceleration at all, just foot to the floor.lol Just my thoughts/comments

Justin

 

I take a long hilly 35mph limit road on my commute. I barely have to touch the gas to cruise at 35mph in 6th even on the hills (assuming I'm already at speed) and why would I need to accelerate quickly with a 35mph limit? I can still downshift.

 

Because at gear at that speed your revs would be, just a guess mind you, like 2100, In short, I don't think you would be matching your revs to your wheel speed very well, IMO 6th is for highway speed, 60-65mph and above and why would you want to cruise in 6th gear at 35mph and then every time you wanted to accelerate downshift, because I can tell you now at 35mph and in 6th gear with a MINI equipped with a 6-seed Getrag transmission you are not going to go anywhere upon even stomping the gas, when you could already be cruising at that speed in a "healthy gear-to-wheel speed" ratio and save your clutch of unneeded use by not having to downshift. But do what you feel natural and best for your car and your driving style.

 

schr5530,

I would think that if the engine isn't lugging you are good-to-go with what you're doing.

Why don't you calculate the gas mileage the old fashion way and see what that reveals?

 

You'll get the best fuel economy in the highest gear. Not sure why you'd want to be cruising at highway speeds in 5'th if fuel economy is the objective.

What matters to the engine is that the RPM be appropriate for the load. If you are applying more load to the engine by accelerating or climbing a hill, you don't want to "lug" the engine by being in too high of a gear (ie, too low of an RPM).

I try to "cruise" at 2500+ RPM. But I downshift to 3000+ RPM for gentle acceleration or climbing a slight incline and 4000+ RPM for more aggressive acceleration or climbing a steeper incline.

 

In my auto I rarely hit 6th gear unless on a fast interstate (75mph+, yes there are 80s out there) or over 100 mph on the track, because 5th, at least on the auto, is pretty tall.

 

I just went on an errand and tried cruising at 35mph in 6th gear and my rpm was below 2k, at that rpm any kind of acceleration will cause the engine to lug and I suppose you could downshift but that brings up the clutch being used when it doesnt really need to be...

 

Well I suppose running 35 mph in 6th gear will maximize mileage, and we probably all have done at one time or another, but it certainly isn't much fun and there is a good chance of lugging. Engine wise there will be happiness in 4th or even 5th if you don't mind very slow movement forward. Oh well what ever makes you happy just do it.

 

I do use pen a paper economy calculations but It's tricky to say what factors had the biggest influence on my economy at each fill up.

Lets Think about this in terms of a bicycle. If I want to go say 10mph.

a) In my lowest gear the pedals move freely but I have to pedal really fast. I would quickly tire and go home.

b) In my highest gear I have to stand on the pedals but I'm moving them really slowing. I would quickly tire and go home.

c) I find a mid range gear where there is a balance between my pedal speed and the amount of force I have to put into turning them. I then have a long enjoyable ride.

I'm just at a bit of a loss on how to find this balance in my car. Which is better 1500rpm and the gas @ 20 degrees or 2500rpm with the gas at 5 degrees?

 

Not sure about the right gear thing, but I get about 40-50 miles out of a banana and a couple of granola bars...

 

Cruise in whatever gear you feel comfortable. I cruise at 2,500 rpm or try to at least. So if the engine speed is higher then that at there is a higher gear I will switch to it.

 

It seems my Justa Cooper gets it's best overall mileage with the RPM between 2000 and 2500. I can temporarily get better mileage by selecting a gear that will lug the RPM down below 2000, but the second I hit even the slightest uphill grade the mileage goes to crap.

I'm used to bigger displacement engines where keeping the RPM down around 1500 nets the best mileage, so it's a bit of an adjustment when driving the MINI.

 

I'm not a "how much mileage am I getting" kind of person......but I do understand, especially in this economy, why it's important. You are honestly not going to get any better gas milage in 6th gear if the car is lugging....you WILL burn more. If you can get away with 35 mph in 5th gear, you will get better mileage (and even 5th gear will lug at times at that speed....4th gear is more realistic).

Porthos is right, 2500 rpm's is about the best range for the motor and will give you the best over-all fuel economy. Now, saying all that......it's a Mini, sometimes you just have to say; the hell with the gas tank, it's time to have some fun

 

Driving around town in 6th gear MIGHT be dangerously close to lugging the motor....if you have the full gauge package...look at your oil pressure...Below maybe 2200 Rpm...I might be wary of excessive combustion temperatures/pressures, possible reducing engine life, or possibly causing carbon buildups. And most important of all, reduced FUN!! Heck...let the SC whine a little...

One thing to keep in mind....on a r53, with the 6 speed is both 5th and 6th gears are overdrive gears...top speed is actually achieved in 5th gear (limited by both RPM/torque, the computer)....and many people report that on highway trips, you get better MPG in 5th gear than 6th (at typical US highway speeds ((below 75))...remember..our car is geared for the autobahn)!!
True....been debated...just used your trip computer, the old miles/gallons, or a scanguage....
The trip computer is actually very accurate..or should I say consistent (once you figure out the % off, it will always be the same % off, and you can actually go into the computer, and enter an adjustment to make it perfect!!
The computer actually uses current fuel consumption, derived by measuring the length of the fuel injector pulse to determine fuel consumption, and then does some math with the speed....and you have instant MPG!!
This is the reason why the trip computer becomes inaccurate when you install larger injectors unless they have been scaled, and a correction made.

 

Okay, I tried driving 35 in 6th gear on basically flat grade, elevation about 4700 feet above sea level...

I have a '09 Mini Cooper Clubman S with a 6 speed transmission. When I register 35 mph in 6th gear my rpm's are around 1,500. The engine isn't lugging but it's pretty darn close! If I shift down to 5th, the rpm just jumps slightly to around 1,600 and if I go to 4th, the rpm is about 1,700. In 4th gear the engine sound okay and I can even accelerate quite easily if needed. In my opinion, driving 35 mph in 6th gear really won't get you much at all as far as fuel economy.

Back in the "good ol' days" a good way to get some idea of how an engine was performing as far as economy was to attach a vacuum gauge and read it while one drove. If the vacuum dropped it meant the engine was lugging and therefore poor fuel mileage. If the vacuum rose it meant the car was accelerating and obviously that meant poor mileage. The key was to keep the vacuum in a specific range. Perhaps someone with more experience with these modern engines will be able to tell me if this still holds true.

 

I don't think any extra wear will be done to the engine as long as it isn't lugging, as others have already stated.

Going for the highest mpg will be acheived in the highest gear and the least amount of throttle, basically coasting.

 

Please remember....Turbo and Supercharged cars behave VERY differently...the driver has a R53 supercharged car....different motor, different gearing....
Turbo cars ARE a bit of a different beast....especially at higher elevations with less wind resistance, AND full power being available....but that being said, I agree with you..even in an TURBO car, with lower wind resistance, and full Torque and HP available, driving in 6th will not save you much...but could cost you!!

 

This is easy. Always drive in the highest gear possible without lugging the engine. If you need to accellerate quickly, downshift. If you're in a situation where you think you might have to accellerate quickly, then downshift ahead of time. As long as you're not lugging the motor and it's not straining to keep vehicle speed, there's no reason to run in a lower gear. And you can skip gear if you'd like. I like to accellerate pretty quickly and I'll go thru 1st, 2nd, and 3rd and by that time I'm thru the on-ramp and at highway speed. At that point I'll go directly from 3rd to 6th. Or 4th to 6th.

 

Here's the best explanation I found....it says basically what most of us have been saying above....;

Just because your engine is running at a lower rpm doesn't mean it uses less gasoline. Using a high gear at a low speed means a lower rpm so it should use less gas, but if you need power to accelerate in a higher gear, more gasoline is injected in order to move the pistons faster. It's the same as going really slow in a high gear on your bicycle and trying to accelerate, you will be laboring a lot to move the bike faster, even though the pedals are moving slowly. So don't labor the engine, it doesn't improve fuel economy. Whenever more than a slight amount of acceleration is needed when in a high gear (relative to the speed), it saves fuel to downshift to a gear suited to the needed acceleration

 

Whatever gear it takes to cruise (on the flat) at between 2000 and 2500rpm...

 

I do know that at 70 mph in 6th gear I'm pulling less rpms in my R56 that at 70 mph in 6th gear in my old R53, about 600 rpm less (2400 vs 3000). Granted, my R56 is an auto and the R53 was a manual, but when I had a manual service loaner S here recently I checked the numbers again and the diff was about the same.

Like I said, the 6th gear in the Aisin auto is very tall, and I rarely use it below 100 mph. I suppose if I was all worried about mpgs and all that stuff Id prob use it more.

 

I own a Clubman S manual and 335i 6 speed and have owned many BMW 6 speeds. As a general rule I would go by rpm's, I wouldn't run below 1500 if it were my car.

 

Yep.