04 STI vibration from the shifter - Page 2

jpsti · 01-02-2004, 11:40 AM

Thanks STiLL!!

ZenBoy · 01-02-2004, 12:08 PM

As I recall, resting your hand on the shifter will not wear the gears, but may wear the synchros and the various rings and such between the gears. I see it as being the same as resting your foot on the clutch, personally.

Regarding the clutch, it doesn't take much pressure to make a difference on the other end of the hydraulics! That being said, putting pressure, even slight, on the clutch pedal is going to very slightly disengage the clutch; personally, I'd rather that the clutch was fully engaged, and that I'm not straining it or encouraging slippage any more than necessary.

M · 01-02-2004, 06:59 PM

If you've ever looked under a vehicle idling in neutral after it's broken a driveshaft or blown a differential, you can see the driveshaft turning. (OK trust me, it does.) That's because the clutch is always slightly engaged unless the pedal is depressed. By slightly touching the pedal, you're making the clutch slip even in neutral. It's not a lot of wear, but resting your foot on the clutch does reduce clutch life and it's one of the cardinal rules of driving a stick.
As far as the transmission, I've not heard much about extra wear but it's another bad habit. Your hands should only be on the shifter to shift, otherwise holding the wheel or as Singletrack so eloquently stated, on your beotch.

bitabur · 01-02-2004, 07:56 PM

Quote:

Originally Posted by M

If you've ever looked under a vehicle idling in neutral after it's broken a driveshaft or blown a differential, you can see the driveshaft turning. (OK trust me, it does.) That's because the clutch is always slightly engaged unless the pedal is depressed. By slightly touching the pedal, you're making the clutch slip even in neutral. It's not a lot of wear, but resting your foot on the clutch does reduce clutch life and it's one of the cardinal rules of driving a stick.
As far as the transmission, I've not heard much about extra wear but it's another bad habit. Your hands should only be on the shifter to shift, otherwise holding the wheel or as Singletrack so eloquently stated, on your beotch.

Your explanation is a bit confused here.... you're saying that even in neutral the car will transmit power to the driveshaft? If that were the case, you would wear the clutch significantly more by keeping your foot off of it than by depressing it. There's no way that's correct.... the car must have been in gear or something.....? Or the car was an automatic? That would be the most horrible transmission design ever if it was a manual in neutral.

M · 01-02-2004, 09:19 PM

Quote:

Originally Posted by bitabur

Quote:

Originally Posted by M

If you've ever looked under a vehicle idling in neutral after it's broken a driveshaft or blown a differential, you can see the driveshaft turning. (OK trust me, it does.) That's because the clutch is always slightly engaged unless the pedal is depressed. By slightly touching the pedal, you're making the clutch slip even in neutral. It's not a lot of wear, but resting your foot on the clutch does reduce clutch life and it's one of the cardinal rules of driving a stick.
As far as the transmission, I've not heard much about extra wear but it's another bad habit. Your hands should only be on the shifter to shift, otherwise holding the wheel or as Singletrack so eloquently stated, on your beotch.

Your explanation is a bit confused here.... you're saying that even in neutral the car will transmit power to the driveshaft? If that were the case, you would wear the clutch significantly more by keeping your foot off of it than by depressing it. There's no way that's correct.... the car must have been in gear or something.....? Or the car was an automatic? That would be the most horrible transmission design ever if it was a manual in neutral.

Yes, that was quite confused. Now that I really think about it, it didn't entirely have to do with the clutch slipping. The example I saw was on a heavy straight truck (GVW=36,000#). I was helping the mechanic move it into the shop and I noticed the driveshaft was spinning pretty slowly but at a constant speed. Actually the first two driveshafts were spinning, the third was broken. I asked the mechanic what was going on, I can't remember exactly how he explained it, but yes, a transmission in neutral can transmit a small portion of power if there is very little resistance. I'll ask him again tomorrow... :roll:

ss3homer · 01-02-2004, 11:30 PM

they just dont want you to screw up and ruin sumptin

STiLLWILL · 01-03-2004, 12:54 AM

Quote:

Originally Posted by jpsti

Thanks STiLL!!

np, anytime. :wink:

-STiLL

bitabur · 01-03-2004, 11:37 AM

Quote:

Originally Posted by M

Quote:

Originally Posted by bitabur

Quote:

Originally Posted by M

If you've ever looked under a vehicle idling in neutral after it's broken a driveshaft or blown a differential, you can see the driveshaft turning. (OK trust me, it does.) That's because the clutch is always slightly engaged unless the pedal is depressed. By slightly touching the pedal, you're making the clutch slip even in neutral. It's not a lot of wear, but resting your foot on the clutch does reduce clutch life and it's one of the cardinal rules of driving a stick.
As far as the transmission, I've not heard much about extra wear but it's another bad habit. Your hands should only be on the shifter to shift, otherwise holding the wheel or as Singletrack so eloquently stated, on your beotch.

Your explanation is a bit confused here.... you're saying that even in neutral the car will transmit power to the driveshaft? If that were the case, you would wear the clutch significantly more by keeping your foot off of it than by depressing it. There's no way that's correct.... the car must have been in gear or something.....? Or the car was an automatic? That would be the most horrible transmission design ever if it was a manual in neutral.

Yes, that was quite confused. Now that I really think about it, it didn't entirely have to do with the clutch slipping. The example I saw was on a heavy straight truck (GVW=36,000#). I was helping the mechanic move it into the shop and I noticed the driveshaft was spinning pretty slowly but at a constant speed. Actually the first two driveshafts were spinning, the third was broken. I asked the mechanic what was going on, I can't remember exactly how he explained it, but yes, a transmission in neutral can transmit a small portion of power if there is very little resistance. I'll ask him again tomorrow... :roll:

Definately do, I'm interested in what was actually going on there....

ZenBoy · 01-03-2004, 07:02 PM

The only reason that drive shaft should be turning is if the truck's rolling. There's a mechanical connection from the driveshaft to the wheels, but the only connection from the driveshaft to the engine is through the clutch.

If the clutch is pressed to the floor and there's still power going to the driveshaft from the engine, it's because the clutch isn't fully disengaged. This could be an adjustment issue, or a broken part.

That's how it works, unless my understanding of it all is messed up.

M · 01-03-2004, 09:03 PM

Alright, I found out. It because the mechanic puts motor oil in the transmission during the summer per manufacturers specs. The oil is really thick and the oil churning inside the tranny at idle is enough to turn the driveshafts. This only happens on heavy trucks when they use motor oil in place of tranny fluid. It had nothing to do with the clutch.
My apologies for the confusion...

ops:

ab954 · 01-03-2004, 11:17 PM

Resting your hand on the shift lever puts force on the shift forks, maybe this causes wear. As far as the clutch, if you rest your foot on it, the throwout bearing comes in contact with the pressure plate and the bearing spins constantly. The throwout bearing is lubed by it's own internal lube(no oil bath), no cooling, and you will burn it out in short order. it is a standard tapered roller sealed bearing. a 20 dollar part that costs several hundred to fix. This is true of all manuels tranny cars. If you depressed the clutch a little more, then it could cause the clutch to slip, causing increased wear.

Antimullet · 01-06-2004, 01:55 PM

STi 187,

To illustrate why you should't ride with your hand resting on the shifter:

Drive slow say in second gear, don't touch the clutch and push the shifter sideways left or right. Don't do it so hard to force it in another gear or you'll break sonmething!! If you did it correctly you'll start too hear a mechanical whining noise coming from the gearbox. This is your hand putting pressure on the synchros which if done habitually will prematurely wear them out, then you get the nice grinding sound of gear teeth being sheared off.

qbbraveheart · 01-06-2004, 02:09 PM

the 4th gear on my prelude does that when i rest my hand on it....my perferred driving position...i dont push my car hard anymore

roadrnr37 · 01-16-2004, 04:22 PM

Ok so let's clarify a few things.

1. resting your ahnd on the shifter during normal driving over long periods can be detramental to your manual tranny because not only can the froks ride on the bearings, forcing them to spin fro no reason, but they can also push the synchro's onto the slides of your gears and wear them out, just like a clutch. Friction in your transmission is not yotu friend.

2. The reason you have residual power traansfer is due to the gears spinning in close proximity to each other with fluid in between, Although this property is a good thing (especailly if you have an automatic trans, that's how they work,= torque converter) but yes there is always a little "push" from fluid movement in your tranny. Think of two large fans blowing really close to each other. If one if going faster than the other, the force from the faster one will move the second one.

3. Yes, that fourth gear vibration is anoying, but if that is the only problem with tranny, and driveline this complex, you will hear no complaints from me.

STight · 01-16-2004, 05:44 PM

Quote:

Originally Posted by sti_187

ok maybe im a little confuse, resting your hand on the clutch is like say your in fourth gear and just leaving your hand there like holding it ryte? how can that do any harm to it, is your hand weight weighing it down or something? yeah it does say in the manuel, and also it says dont rest your foot on the clutch, is that the same thing also, if your foot is on the clutch but your not pressing down on it how can that mess it up. but yeah, my sti in fourth gear you feel more vibration on it also, your not the only one!

I really try hard to keep my hand off the clutch...Guess my arms are not as long as yours....lol

01-02-2004, 11:40 AM	#16
jpsti Amateur STI Driver Posts: 10 Join Date: Dec 2003 Trader Rating: (0)	Thanks STiLL!! This ad is not endorsed by this member. Please register or login to hide this ad.

01-06-2004, 02:09 PM	#28
qbbraveheart Junior STI Driver Posts: 101 Join Date: Jan 2004 Trader Rating: (0)	h4RdC0r3 STi Snow Pictures - 56 Ghey the 4th gear on my prelude does that when i rest my hand on it....my perferred driving position...i dont push my car hard anymore

01-16-2004, 04:22 PM	#29
roadrnr37 Junior STI Driver Car: Math, Physics, Engineering Fav Mod: Manager...... Location: Wayne,NJ Posts: 53 Join Date: Jan 2004 Trader Rating: (0)	S4--->STi folks Ok so let's clarify a few things. 1. resting your ahnd on the shifter during normal driving over long periods can be detramental to your manual tranny because not only can the froks ride on the bearings, forcing them to spin fro no reason, but they can also push the synchro's onto the slides of your gears and wear them out, just like a clutch. Friction in your transmission is not yotu friend. 2. The reason you have residual power traansfer is due to the gears spinning in close proximity to each other with fluid in between, Although this property is a good thing (especailly if you have an automatic trans, that's how they work,= torque converter) but yes there is always a little "push" from fluid movement in your tranny. Think of two large fans blowing really close to each other. If one if going faster than the other, the force from the faster one will move the second one. 3. Yes, that fourth gear vibration is anoying, but if that is the only problem with tranny, and driveline this complex, you will hear no complaints from me.

01-02-2004, 12:08 PM	#17
ZenBoy Grassroots STI Racer Car: 2004 WRB STi Fav Mod: Earplugs. Location: Minneapolis, Minnesnowta Posts: 595 Join Date: Dec 2003 Trader Rating: (2)	As I recall, resting your hand on the shifter will not wear the gears, but may wear the synchros and the various rings and such between the gears. I see it as being the same as resting your foot on the clutch, personally. Regarding the clutch, it doesn't take much pressure to make a difference on the other end of the hydraulics! That being said, putting pressure, even slight, on the clutch pedal is going to very slightly disengage the clutch; personally, I'd rather that the clutch was fully engaged, and that I'm not straining it or encouraging slippage any more than necessary.

01-02-2004, 06:59 PM	#18
M Grassroots STI Racer Location: Indiana Posts: 589 Join Date: Dec 2003 Trader Rating: (0)	If you've ever looked under a vehicle idling in neutral after it's broken a driveshaft or blown a differential, you can see the driveshaft turning. (OK trust me, it does.) That's because the clutch is always slightly engaged unless the pedal is depressed. By slightly touching the pedal, you're making the clutch slip even in neutral. It's not a lot of wear, but resting your foot on the clutch does reduce clutch life and it's one of the cardinal rules of driving a stick. As far as the transmission, I've not heard much about extra wear but it's another bad habit. Your hands should only be on the shifter to shift, otherwise holding the wheel or as Singletrack so eloquently stated, on your beotch.

01-02-2004, 11:30 PM	#21
ss3homer Grassroots STI Racer Car: Modding Business Fav Mod: Day-Trader Location: Denver, The BIG CO Posts: 531 Join Date: Dec 2003 Trader Rating: (0)	they just dont want you to screw up and ruin sumptin

01-03-2004, 07:02 PM	#24
ZenBoy Grassroots STI Racer Car: 2004 WRB STi Fav Mod: Earplugs. Location: Minneapolis, Minnesnowta Posts: 595 Join Date: Dec 2003 Trader Rating: (2)	The only reason that drive shaft should be turning is if the truck's rolling. There's a mechanical connection from the driveshaft to the wheels, but the only connection from the driveshaft to the engine is through the clutch. If the clutch is pressed to the floor and there's still power going to the driveshaft from the engine, it's because the clutch isn't fully disengaged. This could be an adjustment issue, or a broken part. That's how it works, unless my understanding of it all is messed up.

01-03-2004, 09:03 PM	#25
M Grassroots STI Racer Location: Indiana Posts: 589 Join Date: Dec 2003 Trader Rating: (0)	Alright, I found out. It because the mechanic puts motor oil in the transmission during the summer per manufacturers specs. The oil is really thick and the oil churning inside the tranny at idle is enough to turn the driveshafts. This only happens on heavy trucks when they use motor oil in place of tranny fluid. It had nothing to do with the clutch. My apologies for the confusion... ops:

01-03-2004, 11:17 PM	#26
ab954 Amateur STI Driver Posts: 34 Join Date: Jan 2004 Trader Rating: (0)	Resting your hand on the shift lever puts force on the shift forks, maybe this causes wear. As far as the clutch, if you rest your foot on it, the throwout bearing comes in contact with the pressure plate and the bearing spins constantly. The throwout bearing is lubed by it's own internal lube(no oil bath), no cooling, and you will burn it out in short order. it is a standard tapered roller sealed bearing. a 20 dollar part that costs several hundred to fix. This is true of all manuels tranny cars. If you depressed the clutch a little more, then it could cause the clutch to slip, causing increased wear.

01-06-2004, 01:55 PM	#27
Antimullet Professional STI Driver Car: 2005 STi Fav Mod: Big Turbo Location: NORCAL Posts: 471 Join Date: Jan 2004 Trader Rating: (0)	STi 187, To illustrate why you should't ride with your hand resting on the shifter: Drive slow say in second gear, don't touch the clutch and push the shifter sideways left or right. Don't do it so hard to force it in another gear or you'll break sonmething!! If you did it correctly you'll start too hear a mechanical whining noise coming from the gearbox. This is your hand putting pressure on the synchros which if done habitually will prematurely wear them out, then you get the nice grinding sound of gear teeth being sheared off.