Clutchless Shifting?
#1
Clutchless Shifting?
Well, not shifting, really, but taking it out of gear without using the clutch. I do it fast enough that it just comes out of gear, and doesn't grind or anything like that. It all sounds and feels normal. Sometimes I just don't feel like pushing the clutch in to take it outta gear. You know, those early mornings, heading to work with about 5 hours of sleep under your belt. Simply put, will this hurt my tranny, or am I ok? Thanks!
#2
Yes, any kind of clutchless shifting (up, down, in, out) will cause damage and shorten tranny life. Always depress the clutch when changing gears or taking the car out of gear.
Last edited by TheProbeKid; July-18th-2002 at 01:11 AM.
#3
Originally posted by Protégé Ménacé
well, as long as you dotn feel it catching or grinding it isnt too bad.
its called rev matching. there should be lots of info on that in this forum.
well, as long as you dotn feel it catching or grinding it isnt too bad.
its called rev matching. there should be lots of info on that in this forum.
#4
Originally posted by TheProbeKid
..any kind of clutchless shifting (up, down, in, out) will cause damage and shorten tranny life...
..any kind of clutchless shifting (up, down, in, out) will cause damage and shorten tranny life...
[Buzzer sound].... Incorrect contestant #1. You can shift without using the clutch and suffer no ill effects on the transmission. This includes upshifting, downshifting or just coming out of gear. Damage is done by someone that doesn't know what the hell they are doing. If you match revs it will slide right in. Don't force it. If you force it and don't have the revs matched, then you can cause damage.
#7
Originally posted by mito7878
Why even ask this? Does this add 15 hp?
Why even ask this? Does this add 15 hp?
#8
Just keep in mind that coasting is illegal, and if you car is in Neutral and you are moving even the slightest, that's considered coasting. In theory, you should have to put your clutch in to take the car out of gear because by law, the very next thing you do is put it into another gear.
I agree with rodslinger only based on the fact that if your car is at a complete standstill with the engine OFF, you can slide in and out of gear without the clutch without a problem. (Think of this as an extreme case where both parts are moving the same speed or "rev matching")
I agree with rodslinger only based on the fact that if your car is at a complete standstill with the engine OFF, you can slide in and out of gear without the clutch without a problem. (Think of this as an extreme case where both parts are moving the same speed or "rev matching")
#9
other than any legal issues that might arise...
If the tranmission speed matches that of the drive-shaft such that the gears align correctly you do not need a clutch... the reason for the clutch is so that you can get the gears to do exactly that.
If you are sufficiently skilled and careful you can drive without using the clutch at all (w/ the exception of first gear). Ask people whom drive big trucks for a living. Many of them do not use the clutch for up-shifts and many down-shifts, they just carefully match the engine speed to the tranny speed.
You are not going to hurt anything (IMO) if you are taking it out of gear and it is going smoothly. If you are having to pull harder than just very light pressure, or you hear any kind of light clunking sound, then it would be a good idea to use the clutch.
If the tranmission speed matches that of the drive-shaft such that the gears align correctly you do not need a clutch... the reason for the clutch is so that you can get the gears to do exactly that.
If you are sufficiently skilled and careful you can drive without using the clutch at all (w/ the exception of first gear). Ask people whom drive big trucks for a living. Many of them do not use the clutch for up-shifts and many down-shifts, they just carefully match the engine speed to the tranny speed.
You are not going to hurt anything (IMO) if you are taking it out of gear and it is going smoothly. If you are having to pull harder than just very light pressure, or you hear any kind of light clunking sound, then it would be a good idea to use the clutch.
#10
Originally posted by JJB
Ask people whom drive big trucks for a living. Many of them do not use the clutch for up-shifts and many down-shifts, they just carefully match the engine speed to the tranny speed.
Ask people whom drive big trucks for a living. Many of them do not use the clutch for up-shifts and many down-shifts, they just carefully match the engine speed to the tranny speed.
1.They don't have syncros (they would just wear out) so a semi driver can double clutch and rev-match without the ill effects.
2.A transport also has a clutch cone (input bearing) as big as my ,and any trucking company will fire you for not using the clutch...if they find cone wear!
3. A rig also runs at a much lower RPM compared to a car, most diesels (Cummins, CATs, Detroits etc.) redline at 3500 RPM. Try yer f**ckin' rev-matchin at 6-grand, and tell me if the hole tranny hits the ground or not . I wouldn't advise it, 'cause I'd hate to see ya pissed when the tranny goes soup!
#11
Re: Clutchless Shifting?
Originally posted by Maxx Mazda
Well, not shifting, really, but taking it out of gear without using the clutch. I do it fast enough that it just comes out of gear, and doesn't grind or anything like that. It all sounds and feels normal. Sometimes I just don't feel like pushing the clutch in to take it outta gear. You know, those early mornings, heading to work with about 5 hours of sleep under your belt. Simply put, will this hurt my tranny, or am I ok? Thanks!
Well, not shifting, really, but taking it out of gear without using the clutch. I do it fast enough that it just comes out of gear, and doesn't grind or anything like that. It all sounds and feels normal. Sometimes I just don't feel like pushing the clutch in to take it outta gear. You know, those early mornings, heading to work with about 5 hours of sleep under your belt. Simply put, will this hurt my tranny, or am I ok? Thanks!
#13
Having driven semis for many a year, I can probably clear this up somewhat. First off, yes, you can rev match and get your tranny to shift without a clutch. If you aren't good at it, you WILL destroy synchros.
Big rigs don't rev past 2100 RPM now. That is redline on most manufacturers engines and that's where the fuel cutoff is. Years ago some 2 cycle diesels went as high as 3500 RPM but those are no more. They can't even come close to meeting diesel emissions regs now.
Also, there are synchronized big rig trannies out there. Just not many. Volvo made them mainly but there are a couple others. Neat idea, but the new electronic shifting trannies are better. They match engine RPM to ground speed and you either just move the stick or they actually shift automatically. They are still manual transmissions but they are automated.
I've shifted cars without the clutch before but I wouldn't recommend it unless your clutch is dying and you're just trying to get home. It's there for a reason. The trick is to 'break torque' just before you pull the tranny out of gear. If you are going a steady speed, let off on the throttle a little as you move the stick. If you are decelerating, give it just a slight amount of gas as you pull it out of gear. The torque on the gear teeth will keep it engaged and fight you moving the stick if you don't match properly.
Big rigs don't rev past 2100 RPM now. That is redline on most manufacturers engines and that's where the fuel cutoff is. Years ago some 2 cycle diesels went as high as 3500 RPM but those are no more. They can't even come close to meeting diesel emissions regs now.
Also, there are synchronized big rig trannies out there. Just not many. Volvo made them mainly but there are a couple others. Neat idea, but the new electronic shifting trannies are better. They match engine RPM to ground speed and you either just move the stick or they actually shift automatically. They are still manual transmissions but they are automated.
I've shifted cars without the clutch before but I wouldn't recommend it unless your clutch is dying and you're just trying to get home. It's there for a reason. The trick is to 'break torque' just before you pull the tranny out of gear. If you are going a steady speed, let off on the throttle a little as you move the stick. If you are decelerating, give it just a slight amount of gas as you pull it out of gear. The torque on the gear teeth will keep it engaged and fight you moving the stick if you don't match properly.
#14
Originally posted by Brubeck
Just keep in mind that coasting is illegal, and if you car is in Neutral and you are moving even the slightest, that's considered coasting.
Just keep in mind that coasting is illegal, and if you car is in Neutral and you are moving even the slightest, that's considered coasting.
#15
coasting is definately illegal in FL and I'm pretty sure most states, but honestly, is the cop EVER gonna be able to prove you werent in gear; No. It's just a law that protects the driver in a panic situation so that you always have your car in gear. Like say someone cut you off and you had to gun it to change lanes in b/w 2 cars-if you slam the gas in nuetral, well, you hit the car or damage the engine.