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Old 9th February 2012, 12:12   #16
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Default Re: Upshifting from 3rd to 5th - Good or Bad practice

Very interesting to read comments from distinguished bhpians.

As majority of the people commented that they do (frequently or infrequently) upshift from 3rd to 5th I begin to wonder if its actually to do with the short gearing between 3rd and 5th. If yes then why is there a need for the 4th gear? Couldn't there be a taller gap (pardon my technical ignore here) between 4th and 5th such that 5th could only be used as a cruise.


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Originally Posted by Vik0728 View Post
Hey arup just the topic I was keen on posting soon. Really appreciate you bringing it up.
@vik0728 - glad to hear such questions popping up in others mind as well. i thought i am onyl stupid enough to bring this up

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Originally Posted by sgiitk View Post
Shifting should ideally be sequential with no missed gears. However, third to fifth is a common practice. About 30 years ago (when most boxes were 4-speed), it was common practice (esp. in European cars) to have a large gap between 2 & 3 with 3 & 4 close together.
@sgiitk - you've mentioned it a common practice a couple of decades back and the same is being is carried forward today. so are you saying 3rd (those days) and 4th (now) gear are kind of redundant.
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Old 9th February 2012, 12:28   #17
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Default Re: Upshifting from 3rd to 5th - Good or Bad practice

As long as you arent riding the clutch or arent lugging the engine ,I think it shouldnt be a problem to shift from 3rd to 5th .
I do most of the timesin the city and or on the highways.
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Old 9th February 2012, 12:30   #18
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Default Re: Upshifting from 3rd to 5th - Good or Bad practice

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Originally Posted by arup.misra View Post
so are you saying 3rd (those days) and 4th (now) gear are kind of redundant.
Well, it wont make it redundant for sure.
We all use the 4th gear all the time. Especially when overtaking in highways. (My car is not an AMG!!), among other instances.

Had it been the reason, manufaturers now wouldnt have been in a fight for the gear-supremacy... i am hearing a 9 speed box now, Porsche have a 7 speed manual in their latest 911.

If not anything, more the number of gears, better is the power and torque spread and smoothe rcan be your driving.

Drive safe!!!
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Old 9th February 2012, 12:59   #19
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Default Re: Upshifting from 3rd to 5th - Good or Bad practice

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Originally Posted by Valkyrie View Post
Well, it wont make it redundant for sure.
We all use the 4th gear all the time. Especially when overtaking in highways.
This is interesting as some members have said, revv up on 3rd build momentum overtake and cruise on 5th. So where does 4th actually figure.

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Originally Posted by Valkyrie View Post
If not anything, more the number of gears, better is the power and torque spread and smoothe rcan be your driving
Does this mean short 7-speed transmission will be better off than a tall 6-speed transmission?

Please don't mind my questions. Just curious to learn.
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Old 9th February 2012, 13:06   #20
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Default Re: Upshifting from 3rd to 5th - Good or Bad practice

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Originally Posted by arup.misra View Post
Please don't mind my questions. Just curious to learn.
Well I am no expert myself, just putting my views, which is first hand experiences.

Regarding your first query:
Imagine you are driving in a highway at 80~ 100 kmph in 5th gear. A bus is in front of you and you need to overtake it. Your engine rpm will be say around 1500~2000 rpm (??). You will drop down to 4th, rpm increases to say 3000~3500 and you make your move, depending on the traffic.

For the same power output and speed, a 7 speed will have shorter ratios than a 6 speed. (experts, correct me if i am wrong). So you can select any gear depending on the traffic condition and stay with it for longer.

Hope this helps.
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Old 9th February 2012, 13:39   #21
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Default Re: Upshifting from 3rd to 5th - Good or Bad practice

I think shifting from 2rd to 4th or 3rd to 5th was not a good idea in the days of gearboxes without syncromesh. During my highway drives, I frequently shift from 3rd to 5th, and I don't even get a jerk while shifting. Of course, I'll have to rev high on 3rd gear (to 2500 RPM) before shifting to 5th, which brings the RPM to 1700 or so (note that mine is Palio Stile MJD, and it has tall gears from 3rd).

I haven't had any problems with gearbox or clutch for the last 66k km (or 3.5 years).
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Old 9th February 2012, 13:39   #22
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Default Re: Upshifting from 3rd to 5th - Good or Bad practice

IIRC this was discussed in detail on another thread.

I do it all the time on my Baleno in the city - mostly it is 3 to 5, very rarely 2 to 4 and during a sprint from the lights, 2 to 5 also. Given the gearing of the Baleno, even a 1 to 5 is very much possible. I don't see anything wrong in skipping a gear if the engine does not lug.
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Old 9th February 2012, 13:54   #23
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Default Re: Upshifting from 3rd to 5th - Good or Bad practice

I have been doing it all the time, 3rd to 5th, that is. I drive a 2005 Wagon R, and I have seen that this gives me better fuel economy. Of course, the comments about the right RPM are absolutely spot on. So I usually rev upto 3000 in 3rd, and then shift to 5th to bring the RPM down to 1700-2000 range.

Having said that, , I have changed my driving style lately. In short bursts, I rev more than 3000 on 3rd, sometime upto 4000, and then shift to 4th. That brings the RPM to 3000 at speeds of about 80kmph+. I then keep on revving again till 4000. I don't go to 5th at all!

The results: (a) Lesser fuel economy. But no, it doesn't really affect that much if this is done on short bursts in city driving (b) The sense of extraction of more power from the engine (artificial though it may be). The brief moment of sharp overtaking thrill, when all other sedate hatch drivers (no offence meant) wonder why does this guy drive an old Wagon R like this in these days of high petrol prices!

Last edited by Tats07 : 9th February 2012 at 14:01.
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Old 9th February 2012, 14:05   #24
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Default Re: Upshifting from 3rd to 5th - Good or Bad practice

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Originally Posted by arup.misra View Post
What I have observed is that my colleague more often than not would stay on 3rd (not revving high mind you) and soon after hitting the main deck would revv the car the swiftly jump to the 5th bypassing the 4th gear altogether. His logic is, "the lesser you supress the clutch better will be the life. and since you know you are going to shift to 5th quickly why bother to go to 4th". He does the same while downshifting as well. He drives a Polo & Altis (both petrol).

Can learned members enlighten me if this is a correct / good approach and the logic behind the same.

Mods - Couldn't find a similar thread elsewhere hence posting a new topic. Please merge if duplicate detected. Thanks.

I always do this. 3 -> 5 and 5th -> 3rd or 2/4 combination in my Santro.
There is no harm as long as the engine and transmission is not stressed.
My FE in city is approx 16kmpl.
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Old 9th February 2012, 15:05   #25
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Default Re: Upshifting from 3rd to 5th - Good or Bad practice

Quote:
Originally Posted by arup.misra View Post
A very interesting style of driving which I happened to notice prompted me to bring this topic up to get views from our learned community.

My work place is around 20km from home. The route I take is through the Bandra-Worli sealink. My colleague and I alternatively take turns driving every week. As user of this link would know coming from the south end going north, there are a couple of sharp turns especially the one which leads you to the 4-laned main deck. Many a times due to evening traffic the two laned entry from south end is slow progress in 3rd or 4th gear.

What I have observed is that my colleague more often than not would stay on 3rd (not revving high mind you) and soon after hitting the main deck would revv the car the swiftly jump to the 5th bypassing the 4th gear altogether. His logic is, "the lesser you supress the clutch better will be the life. and since you know you are going to shift to 5th quickly why bother to go to 4th". He does the same while downshifting as well. He drives a Polo & Altis (both petrol).

Can learned members enlighten me if this is a correct / good approach and the logic behind the same.

Mods - Couldn't find a similar thread elsewhere hence posting a new topic. Please merge if duplicate detected. Thanks.

Well, unless you are REALLY LAZY, I think you should go through all the gears. Here's why IMO:

1) Fuel Efficency: If you think you are saving on fuel by shifting from 3rd to 5th, think again.
If you are planning to skip 4th, you'll have to revv the engine more in 3rd so that you have enough momentium and RPM to carry through in 5th. Instead shifting to 4th and then 5th does't require you to revv the engine so much as the the gearing is correct (which is why you have 4th gear in the first place!)
More revving= Higher fuel consumption

2) Engine lugging: If the momentum/RPM carried through from 3rd is not enough, you'll lug the engine in 5th, thus messing the con rods/bearings in the bargain.

3) Downshifting- Downshifting at high speed from 5th to 3rd can also cause strain on the engine bearings/conrods. So this is advised only during emergency braking situations.

4) Clutch wear: Saying that you save on clutch wear and tear just by saving on not pressing it once (between 3rd and 4th) is absurd. It's like saying i wont press the brakes so that i can save the brake pads!!! Even if there is wearand tear it will be negligible. Its like losing 1 rupee from a bank balance of 1 lakh!!!

In short, IMO, i'd stick to going through all the gears and give my biceps some exercise in the bargain too

Last edited by noopster : 9th February 2012 at 18:00. Reason: Edited out an expletive. Please avoid using these on the forum even in masked form.
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Old 9th February 2012, 15:32   #26
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Default Re: Upshifting from 3rd to 5th - Good or Bad practice

Quote:
Originally Posted by arup.misra View Post
As majority of the people commented that they do (frequently or infrequently) upshift from 3rd to 5th I begin to wonder if its actually to do with the short gearing between 3rd and 5th. If yes then why is there a need for the 4th gear? Couldn't there be a taller gap (pardon my technical ignore here) between 4th and 5th such that 5th could only be used as a cruise.

@sgiitk - you've mentioned it a common practice a couple of decades back and the same is being is carried forward today. so are you saying 3rd (those days) and 4th (now) gear are kind of redundant.
Originally 5th was designed as a cruising gear only. The gearing was tall so you did not have much of a pick up in the Overdrive (as 5th was called, 4th was normally 1:1). Today's engines have narrower power bands, and gearboxes are designed to take advantage of this. Remember some cars, like Triumph PI came with an add on overdrive unit (on the rear end) which could be switched on in 3rd and 4th, in effect giving you six gears, 1-4, 3OD and 4OD.

3rd and 4th were still required in the four-speed days since on mild slopes you needed the 3rd as the engine tended to (almost) stall in 4th. This worked in most European conditions, but obviously not all. I remember driving in the Alps in my Escort 1300 Mk.I. Due to the big 2/3 gap, in second it was revving a bit too much for my liking while in the 3rd it had a very poor pickup. So you could always find conditions where the ratios were not ideal. Even my Esteem (Carb) had to be brought down from 5 to 4 in order to overtake on the highway esp. with the AC running.
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Old 9th February 2012, 16:49   #27
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Default Re: Upshifting from 3rd to 5th - Good or Bad practice

My limited experience with various Hatches, Sedans and SUV's indicates that there is no absolute right or wrong here, generally speaking.

Why - Because it all depends on the Torque curve of your specific engine and then the Gear Ratios. As long as you pay mind to the Engine Lugging etc..., you should be fine.

Some Examples:
1.
On my Gurkha (TD2650FTI), I almost always start rolling from 2nd. I only use First, when I am commencing the Roll on a steep incline, or against some obstacle. The thing is, the First gear transfers enormous torque, but is very short in range, whereas the Second also transfers a good amount of Torque but happily goes upto when I am doing 40 kmph. This means that I just slot the Gurkha into 2nd in the packed Delhi streets, and keep going. Heck, I don't even have to use the Accelerator most times.

On highways with mild traffic, when I need to do a lot of over-taking, I keep running in 4th. It keeps me happy from about 70 kmph to 110 kmph. Only when I need to cruise at 100+ I slot in the fifth.

When downshifting from fifth due to thickening traffic etc..., I usually need to come down to third, and skip the fourth. But, that's okay. It would be redundant if I came into 4th, since I would be able to maintain it hardly for a second or two, and the third allows me a comfortable range of 30 kmph to 80 kmph.

2. On my Logan (1.5 DCI), I have a very Sweet First gear, that has a pretty long range, and a Second gear that is spaced quite close to the Third. I cannot get into Second, too early because it is very tall, and if I am accelerating quickly, to catch up with the usual Traffic speeds, I find it easier on the engine to slot it directly into third. Over the past 5 years of using the Logan, I have not had to replace my Clutch so I can at least say, that there is nothing much that I am doing wrong.
At the other end, the 5th has a very long range, due to the Torque band of the engine, and I can use it from anywhere like 50 kmph to 120+ kmph. The In-Gear acceleration in that range is very smooth and sufficient for Normal Driving. However, I would bring in the Fourth Gear into play during Spirited Driving.
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Old 9th February 2012, 17:42   #28
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Default Re: Upshifting from 3rd to 5th - Good or Bad practice

I do this 3>5 shift quite often in my Esteem, of course under the right conditions.
Primary reason is FE; in any case, I'm not an aggressive driver so it fits into my style as well.
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Old 9th February 2012, 18:55   #29
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Default Re: Upshifting from 3rd to 5th - Good or Bad practice

When we jump a gear (from 2-4 or 3-5) there is no problem ever. but only have to make sure that there are enough revs for that gear. If there are enough revs then you good. About downshifting it is a normal practice to skip gear provided you are not at a speed that the gear cannot handle.

All in all there will be no problem for skipping a gear provided you are at the right rev level. I always jump gear while downshifting. But never ever skipped a gear while up shifting.
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Old 10th February 2012, 21:05   #30
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Default Re: Upshifting from 3rd to 5th - Good or Bad practice

I have been doing 3-5 when accelerating, say go till 70 in third and then shift to 5th. In extreme cases I do 2-5 - rev till 80 in second and then straight to fifth. Been doing this with my Esteem and now with K10 for over twelve years. This is mainly on the highways, primarily when overtaking. Of course while driving in city, there is no point as you can barely cross 60 most of the time. Both these cars are below 6k RPM at 80 in second so it is safe.
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