M6 guy
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From: Lincoln, Ne
M6 guy I was just curious to see how many of you guys out there who drive the 6-speed cars. Downshift them when coming to a stop? I do quite often, always rpm matching. Anybody seen any negative effects on their cars from this?
i do it occasionally but not very often...the only thing i can see is clutch wear (even if you do rev-match) and higher gas consumption...shouldn't neccasarily be a bad thing
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From: its fucking cold
Originally Posted by 777
i do it occasionally but not very often...the only thing i can see is clutch wear (even if you do rev-match) and higher gas consumption...shouldn't neccasarily be a bad thing
Here's something to think about when downshifting to slow down.....which is cheaper to replace, a clutch or brake pads? That's why i don't downshift to slow down.
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From: its fucking cold
Originally Posted by 777
good point, are you sure about the gas part...that almost doesn't even make sense...is this just your theory or is there a place i can read about it
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I always have downshifted manual cars, thats how I was taught and I thought thats the way the cars were designed. In an auto your car downshifts for you to help save the brakes. I have never replaced a clutch in the three manuals I have owned or done any transmission work. 110,000 miles, 89,000 miles and 48,000 miles on each. I have only had to have the brake pads replaced on the 110,000 car, the other two no brake work.
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From: Quad Cities, IL
I have to believe, to some extent, that rev-matching while downshifting will consume more fuel than if you dont down shift at all. You have to use gas to rev-match, I dont think it's revving on air alone.
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From: its fucking cold
the ammount of fuel consumed by rev matching while not placing a load on the engine would not even be noticed....we are talking less than 1/100th of 1 mpg. It might drop you from 20.01 mpg to 20.00.
depending on your DFCO (Deceleration fuel cutoff) setting is whether or not your fuel consumption is conserved or expended... engine load keeps the motor vacuum but with the TB shut, the lack of airflow is matched with reduced fuel so that deceleration occurs while in gear... With that said... this "load" is primarily transfered to the drivetrain and therefore reduces the lifetime of associated parts...
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In an auto your car downshifts for you to help save the brakes.
The only auto I've been in that had any compression breaking (without manually shifting) was a 4:1 geared 4x4 with 3.73 gears.
So no, it doesn't.
I have to believe, to some extent, that rev-matching while downshifting will consume more fuel than if you dont down shift at all.
And engine braking wears your engine faster, shouldn't be hard on the clutch at all.
I for one will get some use out of those big *** brake disks I have.
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From: Quad Cities, IL
Originally Posted by z98
No. The TB is closed, no fuel is being added except what would usually be added at idle.
Originally Posted by 99formulaM6
I do it sometimes if I need to slow down in a hurry
well i guess i wont do it anymore. lol. if these people on here are downshifting to help save the brakes, how would downshifting when already on the brakes not help you to slow quicker?
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From: North Carolina
bout the only downshifting i do is going down in gears while the clutch pedal is to the floor. the clutch cost more than brakes, along with more time consuming. sometimes i do shift through the gears without the clutch, its very easy on the camaro m6.