Chemical Guys Citrus Wash..What a suprise!

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Bobby G

New member
by David W. Bynon



It’s not our fault. We were simply handed down a bad habit. Although it may seem to be the natural thing to do, and it certainly sounds great in sports cars, down shifting to slow down is bad for your car. By down shifting to slow your car, instead of using your brakes, you put more wear and tear on the clutch, transmission synchronizer rings, and the engine crankshaft.



Clutches and transmissions are expensive to repair. The average clutch replacement is $900 to $1,800. It’s not uncommon for a clutch replacement in a high performance sports car to cost upwards of $2,500. Compare this to the $250 to $300 cost of replacing brake pads, and it’s not hard to figure out that replacing the binders is a lot more economical than running through the gears.
 
Downshifting is an art.



Learning to 'Heal and toe' properly would take a lot of the wear out of your syncs and clutch assembly.



Downshifting is also part of driving a manual car, and should not be avoided.
 
Heal-and-toe for smooth, quick transition into a higher or lower power band... you bet! Downshifting to scrub off speed? I think I'd agree with you differently. If you downshift to reuce speed in a race or high performance driving, you take a higher risk of mecanical failure.
 
I agree, while a decelerating engine sounds really nice.... brakes cost a hell of a lot less than transmission parts.
 
Rcs476 said:
I agree, while a decelerating engine sounds really nice.... brakes cost a hell of a lot less than transmission parts.
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how long do you figure it would take to wear out a clutch/transmission if one always did this. Just out of curiousity, I have no idea myself. This is my first manual car, what the hell is the heel toe thing. I am still used to driving an auto, the other day I slammed on the brakes to avoid an accident(all happened in less than a second) and I forgot to push the clutch in and stalled the car :rolleyes: . lol, sometimes i forget im driving manual with such a smooth shifter in the IS300.
 
Let me put it in these terms... I wore out the clutch in my first 911 in 10,000 miles. After changing my habits (I still drive hard), the clutch in my second 911 lasted 60,000 miles. Not the same car, and Porsche might have made some improvements, but it's the same basic technology.



Heal-and-toe driving is a method of shifting where you cover both the brake and the gas peds with your right foot. Transition time between brake and gas is nil. Takes practice... creates a cramp in your leg/foot if you don't do it right.
 
I'll have to see what I can dig up. I'm writing a new book that includes a chapter on high-performance driving. I have not gotten to the H&T section yet.



db
 
AlBoston said:
This is my first manual car, what the hell is the heel toe thing. I am still used to driving an auto, the other day I slammed on the brakes to avoid an accident(all happened in less than a second) and I forgot to push the clutch in and stalled the car :rolleyes: . lol, sometimes i forget im driving manual with such a smooth shifter in the IS300.
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I wish my first stick was an IS 300!! :D I am seriously jealous though. BTW, I think this site has very good shifting advice: http://www.happytogether.com/318ti/notebook/shifting/index.html
 
AlBoston said:




how long do you figure it would take to wear out a clutch/transmission if one always did this. Just out of curiousity, I have no idea myself. This is my first manual car, what the hell is the heel toe thing. I am still used to driving an auto, the other day I slammed on the brakes to avoid an accident(all happened in less than a second) and I forgot to push the clutch in and stalled the car :rolleyes: . lol, sometimes i forget im driving manual with such a smooth shifter in the IS300.
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No accurate time measure, not even a definite failure, it's just unnecessary wear on the syncros. What does your car weigh, 3500 tops? The IS has some great brakes to begin with, they are more than suitable to stop or slow the car in most situations. If it were a 18 wheeler, it would be a different story. Though, in wet and slippery conditions, I would say sometimes downshifting with proper rev matching is very helpful for slowing.



Heel toe doesn't have a lot of use in day to day driving, though on days when you want to go for some spirited driving though your favorite twisty sections of roads, it is really fun. It is more or less downshifting while braking and rev matching all at the same time, takes tons of practice to get it right, but once you do, you will make some really smooth transitions around tight curves with the power readily available to pull you out of the curve.
 
There will be very little or no damage to the transmission if you double clutch and rev match while you downshift. I recently started to do this and it works wonderfully. The double clutching saves the syncros (although newer cars have syncros desgined to last 200k+ miles), and the rev matching saves the clutch. I've got it down pretty good now, with a perfect rev match into the lower gear.
 
Learning to heel n toe is an art, and so is teaching someone to heel n toe. I have been in many cars on the track showing people how to do it, stop, let them inot the drivers seat and [it depends on the person] they either rev the engine to redline or you endup with your face in the windscreen. It iis humbling expereince the first time you do it. Some people catch on in no time, some people never do. I was, honestly, in the group that needed more time to get it right. I think that is why I'm more patient when instructing [been there, donme that, alot.]
 
i can prove downshifting does not wear the clutch down. I have been handed down a red 1997 ford f-150 4.2L 5 speed manual. My older two brothers and i have been tought to drive manual in that thing, then given to the oldest one until he was 18 then passed down.



My dad, who taught us how to drive manual, used to drive a package car for UPS then he taught UPS drivers how to drive. All Ups trucks are manual. He showed us how downshifting is ok. he taught us to do it.



Now i have the red truck with about 120,000 miles on it. Never had anything done to the tranny except fluids. No gears, clutcth, or ANYTHING. that wit 120,000 miles. Tranny is still just liek the day we got the truck. Perfect.
 
I just make sure the PRNDL meter says D and off I go and stop.:D



But seriously, I will state this ....



Any time the clutch comes into contact with the flywheel there is wear on the clutch ubtil they are static with respect to each other and the slippage has disappeared....now the difference in speed between the clutch and the engine along with pressure from the pressure plate will dictate how much wear you have.



Gears wear when ever they are transmitting a load at a speed. The higher the speed and the higher the load the more wear... Metal on metal wears out eventually.



Based on the above everytime you press in the clutch and then release it you are wearing out your clutch. Everytime your transmission sees torque and rpms from the engine it is wearing out.
 
Guess My Name said:
I just make sure the PRNDL meter says D and off I go and stop.:D
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Sounds good to me!! :D I'm so damn lazy...19 going on 65! So are u saying don't downshift because there is wear on engine/tranny v. just the clutch??
 
That some have taken my little commentary the wrong way. If anyone thinks I don't downshift... you'd be "way" wrong. I do. I downshift to put my engine in the best powerband to get the job done. I'm a very sporting driver, and my clutch and transmission get used a lot.



What I'm saying is, using the drivetrain to brake is hard on the drivetrain. Brake pads and rotors are designed to stop the car, the engine and transmission are designed to make it go.



... and that's all I have to say about that! :cool:
 
Brakes are made to stop. In the past when braking systems were not as efficient as they are with today's quad power assisted disc systems on most cars engine/transmission aided deceleration was required to shorten stopping distances in even less than extreme situations( racing, auto-crossing, etc.). Engine braking can be used in manual transmission cars by just remaining in the last gear engaged and allowing the decreased RPM's to aid in stopping. To state that it is necessary, sporty and requires a adroit heel-and-toe technique to efficiently slow down a stick equipped modern car is just not true. If you must downshift to brake do so with the knowledge that this is a unnecessary activity that is creating extra wear and tear on the transmission, crank bearings. valve drive, driveshaft, u-joints, rear-end, etc. Downshifting maybe a driving pleasure but not a free ride.:cool:
 
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