"Do not downshift into first when ... moving faster than 15 mph"

[shogun32]

why is there an explicit "will damage" warning in the manual.

lawyers who can't drive, why else? They can't say 'don't shift to 1st unless below 58mph' based on calculations of likely rear-axle (3.55) and tire size causing the motor to go into over-rev.

Or thru clumsy clutch use cause a big change in wheel torque and end up doing their best sideways move leaving a car meet.

They could have said, 25mph, hell even 30. But they made it 15 because at 15 it's harder to get into trouble and frankly there is no good reason to change down to 1st above 15-20mph in anything resembling public street driving. Unless being a twat.

WAY too many people simply do not know how to use a clutch properly and don't understand the concept of rev-matching at all and so also the statement is used to reduce wear and tear (aka damage) on the friction disk(s).

It's unwise to look for "engineering truths" in an owners manual. If there are facts and figures they are 50/50 just plain wrong.

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[Wyzz Kydd]

I'll be driving along at 70mph for 5 minutes before I remember, oh yeah 6th gear. And that's with 3.73 gears and D4. Like on the Camaro it's nothing but a fuel efficiency dodge. It's serves no other purpose.

I'm curious, I assume you're talking about the Mustang and shifting to 6th at 70 mph. What about your Camaro? I typically don't go to 6th unless I'm over 70 mph. 5th is my overdrive for 50-70ish.

lawyers who can't drive, why else? They can't say 'don't shift to 1st unless below 58mph' based on calculations of likely rear-axle (3.55) and tire size causing the motor to go into over-rev.

Or thru clumsy clutch use cause a big change in wheel torque and end up doing their best sideways move leaving a car meet.

They could have said, 25mph, hell even 30. But they made it 15 because at 15 it's harder to get into trouble and frankly there is no good reason to change down to 1st above 15-20mph in anything resembling public street driving. Unless being a twat.

WAY too many people simply do not know how to use a clutch properly and don't understand the concept of rev-matching at all and so also the statement is used to reduce wear and tear (aka damage) on the friction disk(s).

It's unwise to look for "engineering truths" in an owners manual. If there are facts and figures they are 50/50 just plain wrong.

For sure. This is one of the reasons I always have rev match on. Easier on the clutch.

 

[shogun32]

I'm curious, I assume you're talking about the Mustang and shifting to 6th at 70 mph. What about your Camaro? I typically don't go to 6th unless I'm over 70 mph. 5th is my overdrive for 50-70ish.

yes I drive both cars the same. 70mph before I even think/remember about there being a 6th gear. I spin both motors like god intended.

 

[Cobra Jet]

you were lucky. Had the clutch held you'd have grenaded the engine from overspeeding the rotating assembly. Fuel shut-off wouldn't have saved it since mechanical drive from the wheels would have overwhelmed it.

^^^^ THAT is exactly correct....


I had lots of fun in the 90's-early 2000's having owned a 1995 E36 M3 and reading the BMW forums with all the idiots who "money shifted".... not just on the street but even tracking their car. That terminology was in force on such euro forums because at that time, a 1995-1999 E36 M3 engine replacement wasn't exactly pocket change.

I wouldn't even ponder why it's not recommended to shift into 1st gear from any speed - and it's puzzling as to why this is still a discussion now pages in...

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If some don't understand or don't agree with what the Owner's Manual states and what's being said here, just go out and test shift your S550 into 1st or 2nd from a much higher speed/RPM and report back (with in-car video)....

 

[Stang55]

That is how I shift. That wasn't the question being asked.

That being said, a downshift into first puts no more stress on the syncros than an equivalent downshift in any other gear. The only thing the synchros effect is the rotational speed of the input shaft, the change in inertia of which is a function solely of the change in rpm from one gear to the next. There's far more force transmitted through the cones in the synchros doing a skip gear shift (up or down) than from shifting into first at 16 mph.

For some reason creeping in traffic like cluching out in 1st or 2nd then clutching back in all the way to slow down, when I shift it to 3rd the syncros love that. Even though the speed is suitable for a 2nd gear creep but you could go faster letting out the clutch in 3rd and it just slides into 3rd with no effort.

 

[Toretto]

I almost never downshift to 1st...i think the only times I've done that is to "show off" (I was also 23 then). I'd say 99.9% of the time I would downshift eventually to 2nd gear till stop, but that's about it. I've driven stick shift for 18 years and never seen the need to downshift into 1st.

 

[Stang55]

I almost never downshift to 1st...i think the only times I've done that is to "show off" (I was also 23 then). I'd say 99.9% of the time I would downshift eventually to 2nd gear till stop, but that's about it. I've driven stick shift for 18 years and never seen the need to downshift into 1st.

I think in an uphill situation thats the only time I would downshift to first but even then I'd have my right hand hovering over the E-brake so as not to roll back.

 

[Zrussian13]

Just because the rpm difference may be the same between 2-1 at 15mph as a 3-2 or 4-3 shift at different speeds the torque multiplication when going into first is much greater due to the sizing of the gears. That's were damage will come from. Is it guaranteed to break on the first try. No but I still wouldn't make a habit of it. My wife did it once in my car at about 15mph. Thank God for rev match! Right in front of a cop too. I'm sure he thought she was fucking with him!

 

[Sivi70980]

I almost never downshift to 1st...i think the only times I've done that is to "show off" (I was also 23 then). I'd say 99.9% of the time I would downshift eventually to 2nd gear till stop, but that's about it. I've driven stick shift for 18 years and never seen the need to downshift into 1st.

I mean, you do live your life one quarter mile at a time...

 

[Stang55]

Just because the rpm difference may be the same between 2-1 at 15mph as a 3-2 or 4-3 shift at different speeds the torque multiplication when going into first is much greater due to the sizing of the gears. That's were damage will come from. Is it guaranteed to break on the first try. No but I still wouldn't make a habit of it. My wife did it once in my car at about 15mph. Thank God for rev match! Right in front of a cop too. I'm sure he thought she was fucking with him!

True, downshifting is only beneficial when you have quite a long distance to stop, with shorter distances usually you stop downshifting by 2rd or 3rd and use your brakes for the rest of the way. You won't be the first to downshift into first many people do it but that doesn't mean its the right way to handle your stick. I have brembo's so maybe my brakes are stronger than others.

 

[shogun32]

True, downshifting is only beneficial when you have quite a long distance to stop, with shorter distances usually you stop downshifting by 2rd or 3rd and use your brakes for the rest of the way.

Brake pads are $100. Transmission is $3000. ALWAYS use brakes to stow/stop.

 

[Toretto]

I mean, you do live your life one quarter mile at a time...

it don't matter if you win by an inch or a mile...winning's winning

 

[Stang55]

Brake pads are $100. Transmission is $3000. ALWAYS use brakes to stow/stop.

Yeah, you shouldn't be going that fast on public roads anyways if your using your transmission to help you stop because the brakes are in abs.

 

[friedmud]

Brake pads are $100. Transmission is $3000. ALWAYS use brakes to stow/stop.

Meh - then I can’t belt those sweet autoblips out to everyone around me!

Been driving manual cars for 20 years - have always coasted down in 3/2/neutral and stopped… but with this autoblip I find myself walking down through the gears nearly every time!

 

[Vlad Soare]

Been driving manual cars for 20 years - have always coasted down in 3/2/neutral and stopped… but with this autoblip I find myself walking down through the gears nearly every time!

Me too.

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