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Old 18th February 2012, 16:08   #46
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Re: Upshifting from 3rd to 5th - Good or Bad practice

To be honest, I dont really notice my gear changes while driving. May be I am too much used to my Scorpio. I do not look at RPM before shifting gears. Everything depends upon driving conditions and driving actions happen as they should. Only when I notice something and want to pay more attention, I give attention to additional input. I am much comfortable with feedback from my Scorpio in terms of slight engine sound / vibration to decide my driving style.

But I never felt the need to skip any gear in my cars during last 10 years of driving.

May be mine is too old driving style.
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Old 18th February 2012, 16:49   #47
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Re: Upshifting from 3rd to 5th - Good or Bad practice

Quote:
Originally Posted by dheepak10 View Post
But then, the damage is not immediate, but happens in the long run.

In the case of downshifting, we generally tend to skip gears only when the speed reduces significantly. So, it should have the same ill-effect as in the case of upshifting.
I agree. Also, to get a smooth shift from 3rd to 5th you need to do rev matching and release the clutch bit more slowly (to avoid jerky motion)
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Old 18th February 2012, 17:05   #48
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Re: Upshifting from 3rd to 5th - Good or Bad practice

I don't think I like it the times when I accidentally shifted from 3rd to 5th. You can't match the revs or the ratios. And it is pointless.
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Old 18th February 2012, 18:56   #49
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Re: Upshifting from 3rd to 5th - Good or Bad practice

There is the 4th gear for a reason and I do not upshift from 3rd to 5th. There will be considerable lug in the engine and transmission with any dose of rev matching. Personally, I don't do it and won't recommend it.

Downshifts though are a different story. When I'm braking from a 100 to a crawling 20, I cannot downshift sequentially (unless I have the time) and I reckon it is perfectly alright to do so. In fact, one cannot do a 4th in 20 km/h. So yeah, upshifts, strictly sequential, downshifts, as the situation demands.
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Old 18th February 2012, 19:43   #50
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Re: Upshifting from 3rd to 5th - Good or Bad practice

3 to 5 have been doing it for many years on high ways, after revving up the engine and speed around 40-60 bracket.

In the city however 5th gear is never used!
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Old 19th February 2012, 00:09   #51
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Re: Upshifting from 3rd to 5th - Good or Bad practice

It is comfortable to bypass 4th if the odo crosses 55+ in 3rd. Mostly I do when the road (highway or city) ahead is clear and fit for 5th.
Also have seen some people move their vehicle directly in "2nd gear" and revving the engine till it gains the momentum. Really horrible.
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Old 19th February 2012, 00:36   #52
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Re: Upshifting from 3rd to 5th - Good or Bad practice

If it were a good practice then I think car makers wont have given the 4th gear. And they have guys who are paid handsomely to analyze this stuff and come up with right suggestions.
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Old 19th February 2012, 01:05   #53
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Re: Upshifting from 3rd to 5th - Good or Bad practice

I do this most of the time on highways, in my Alto K10. Its a pleasure to rev that sweet motor all the way up to 5k RPM in 3rd till about 100 kph, hold that plateau for a few seconds, and then shift directly to 5th to "stretch her legs"

Did this recently on a Madras-Bangalore-Madras trip, on the GQ

Breathtaking!
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Old 19th February 2012, 11:03   #54
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Re: Upshifting from 3rd to 5th - Good or Bad practice

Quote:
Originally Posted by dheepak10 View Post
When you shift from 3rd to 5th, the synchronizers get a little more wear since they have to pull the RPMs down further with the longer gear ratio shifts you're doing, because the RPM for a speed of 40kmph @ 3rd gear is more than the RPM for 40kmph @ 4th gear, which in turn is more than 40kmph at 5th gear. Say you shifted from 3rd at 5000 RPM, to 5th. The synchronizer would have to pull the clutch disk RPMs down from 5000 to about 2500 or 3000. A normal shift from 3rd to 4th only has to drop the RPMs a few hundred or so.
What would you think about shifting directly to 5th from neutral when the car's moving at 60?

Last edited by Samurai : 19th February 2012 at 12:22. Reason: quote only the relevant part
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Old 19th February 2012, 20:06   #55
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Re: Upshifting from 3rd to 5th - Good or Bad practice

Downshifting or upshifting is okay as long as the engine is not being strained. Moving from from neutral to 5th when the car is moving at 60, sounds plausible to me but wouldnt there be some strain which the gearbox would have to bear?
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Old 20th February 2012, 11:02   #56
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Re: Upshifting from 3rd to 5th - Good or Bad practice

Quote:
Originally Posted by skandyhere View Post
What would you think about shifting directly to 5th from neutral when the car's moving at 60?
Shifting from any gear to neutral is fine and would not have any impact on the engine/gear components.
The wear would however be on your brakes, as you would be disengaging the engine braking completely and take all the pressure on the brakes.

On the other hand, sudden downshifting from 4th or 5th to 2nd might take a toll on the engine if the speed is not within the permissible limits for the gear.
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Old 20th February 2012, 11:21   #57
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Re: Upshifting from 3rd to 5th - Good or Bad practice

Quote:
Originally Posted by dheepak10 View Post
the synchronizers get a little more wear
You seem to be the only person on this thread who correctly understood the implications of an otherwise bad habit of going from 3 to 5th or vice versa.
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Old 20th February 2012, 13:00   #58
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Re: Upshifting from 3rd to 5th - Good or Bad practice

I used to do this on my petrol car, however since the new Quadrajet is in, do not want to unnecessarily put pressure on the engine.

However in the 42k kms run on my U-VA, this did not cause any issues.
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Old 20th February 2012, 13:57   #59
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Re: Upshifting from 3rd to 5th - Good or Bad practice

@dheepak10, the query by skandyhere was about shifting directly from neutral to 5th when car is @ 60kmph, not about 5th to neutral.

Last edited by supremeBaleno : 20th February 2012 at 13:59.
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Old 20th February 2012, 14:09   #60
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Re: Upshifting from 3rd to 5th - Good or Bad practice

A bit OT, but how about this.

In the Safari TCIC I was able to change from 2->3->4->5 and back down from 5->4->3->2 or even 5->3 without pressing the clutch, just using the brake and acc and ensuring the revs and speed matched the gears.

Of course it required concentration and I would do this mainly on the Easter and Western Expressways in Bombay just for the fun of it. The gearbox did do fine till 175,000 kms - and possibly beyond - when I sold of the vehicle.

Yep, Yep this is OT but it is just that the gearbox of modern vehicle (not AT) are built so surdy that I feel we worry too much about damaging them through some of the unusual gearchanges that we do. The only reason to skip gears while upshifting is plain lazyness (as mentioned in an earlier post by me.). Though while shifting down there could be many valid reasons.
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