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accelerating downhill

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Old Sep 20, 2009 | 08:09 PM
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Default accelerating downhill

this has happened me a couple of times since getting the gs300 awd a few months ago. so i'm going downhill...at probably 35-45 mph and i may have tapped on the accelerator or may have been just cruising but the transmission jumped up a gear or so... did not feel natural. the rpm went up and the engine got louder....

is this normal? never experienced this on any of my other auto transmission cars - accord, jetta, crv, etc.
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Old Sep 20, 2009 | 08:13 PM
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happens to me all the time..
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Old Sep 20, 2009 | 08:14 PM
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as in it dropped down a gear? (i think this is what you meant because the rpms went up) my 00 gs4 does this, i suppose it is acting as a brake. (sort of)
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Old Sep 20, 2009 | 08:34 PM
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This is normal. It's downshifting for engine braking
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Old Sep 20, 2009 | 08:47 PM
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Yup, that is normal........
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Old Sep 20, 2009 | 09:49 PM
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yup ... its engine braking for you so your car doesn't run away
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Old Sep 21, 2009 | 12:38 AM
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Originally Posted by TWong1200
This is normal. It's downshifting for engine braking
yup, that's drop in gear to use engine braking. it happens when you go downhill (car starts to accelerate) and then you tap on the brakes. the computer system is smart enough to sense that and downshift, avoiding using excessive brakes
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Old Sep 21, 2009 | 01:21 AM
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i've always wondered, is engine braking bad for the engine?
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Old Sep 21, 2009 | 05:12 AM
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Originally Posted by dunnojack
i've always wondered, is engine braking bad for the engine?
Nope its actually lot better then using regular brakes. Back in russia all people did there was engine brake.
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Old Sep 21, 2009 | 08:04 PM
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up to a certain extent, it CAN damage ur transmission, can't it?
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Old Sep 21, 2009 | 08:16 PM
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I did this in most of my previous cars being manual and never had one problem with my trans.

I wonder how many would use the paddle shifters if they where on the 3gs?
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Old Sep 21, 2009 | 08:51 PM
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i noticed the sametihng when im going 40mph (around there) going to work and i hit this miny hill and i try and slow down and the needle goes up on the rpm and engine gets loud. thank god people say its normal i feel better now haha
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Old Sep 21, 2009 | 11:00 PM
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Originally Posted by XxGoKoUxX
up to a certain extent, it CAN damage ur transmission, can't it?
when you put things to the extreme, it could always be a problem.

engine braking won't hurt the engine nor the tranny, as long as it's done correctly. if every time you down shift a lot and rev the engine to very high rpm, i am sure over time it will put extra stress on the engine / tranny.

but if you are doing it correctly, just downshift say a gear and the rpm jumps 500rpm, it's not going to hurt anything

that applies to both auto and manual
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Old Sep 22, 2009 | 11:39 AM
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Some people driving stick shift will over down shift, revving the engine way pass 4 to 5000, I notice that many drivers from 3rd world countries do this for some reason. Maybe it is a way to save on brakes, but I would think it’s cheaper to replace the brakes than the power train. Another thing I notice is that they tend to shift a auto transmission into neutral every time they stop.
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Old Sep 22, 2009 | 12:41 PM
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Originally Posted by The G Man
Some people driving stick shift will over down shift, revving the engine way pass 4 to 5000, I notice that many drivers from 3rd world countries do this for some reason. Maybe it is a way to save on brakes, but I would think it’s cheaper to replace the brakes than the power train. Another thing I notice is that they tend to shift a auto transmission into neutral every time they stop.
yes, over reving is of course not good. that's the time when you said "brake pads are cheaper than your tranny"

putting it on neutral, it can actually be a good habit in places with a lot of slopes. for example in hong kong, where roads are narrow and sloppy, i believe when you learn driving, they ask you to put the car in neutral when you are at the light.
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