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Downshifting... Is it a killer?

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Old Aug 8, 2003 | 01:30 AM
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Default Downshifting... Is it a killer?

Ok i have heard rumors that if you downshift when you go downhill to use engine compression instead of your brakes (as i do) you kill the tranny. Now does it actually kill the tranny enough to be worse than if I were to just lay on my brakes and pay for pads a lot? I downshift a bit cause i live in the hills of KY but i figure it couldnt really hurt because its what the tranny was made for just with the pressure on the other side of the gears.... Any input?
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Old Aug 8, 2003 | 11:47 AM
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Do you mean like useing the lower gears? Like putting it in D or 2 when going down hill? I didn't think it would hurt if you are going down hill. I would rather do that than burning the brakes up slowing down (brakes fading). I wish cars came equipped with jake brakes like trucks then there won't be any problems.
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Old Aug 8, 2003 | 02:58 PM
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I always thought it was bad for the tranny...... but I'm no mechanical guru...
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Old Aug 8, 2003 | 07:59 PM
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I would say that engine breaking wouldnt harm the tranny unless your RPM'* were really high. But I wouldnt trust my word until mechanical genius puts in their word. :?
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Old Aug 8, 2003 | 08:23 PM
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Price out a set of front brakes and rotors and compare that to a new tranny.
Not only does it harm the tranny ( high preasure) but also adds unneeded motor loading, other than a cool sound when down shifting there is no benifit.
As for diesel 'jake' brakes there is no comparison, my car has like 8.5:1 compression while my truck has over 15:1, the way the jake works is by exhaust preasure something a gaser cant handle ( back fire through the intake comes to mind?)

Just my 2 cents
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Old Aug 8, 2003 | 09:00 PM
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Originally Posted by PontiacDad
Price out a set of front brakes and rotors and compare that to a new tranny.
Not only does it harm the tranny ( high preasure) but also adds unneeded motor loading, other than a cool sound when down shifting there is no benifit.
As for diesel 'jake' brakes there is no comparison, my car has like 8.5:1 compression while my truck has over 15:1, the way the jake works is by exhaust preasure something a gaser cant handle ( back fire through the intake comes to mind?)

Just my 2 cents
I used to drive trucks and I knew the jake brake was just an engine retarder. The sound was something I can't explain.
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Old Aug 9, 2003 | 01:26 AM
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well the owners manual suggests to downshift on hills to reduce the premature failure of the brakes
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Old Aug 9, 2003 | 11:51 AM
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Originally Posted by shortstuf2124559@aol.com
well the owners manual suggests to downshift on hills to reduce the premature failure of the brakes
I was about to say the same thing, I remember reading the owners manual for my dads car way back ( toyota camry) and they DID recomend using a lower gear to slow down ( engine brake). Haven't read the owners manual for the bonnie yet though.
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Old Aug 9, 2003 | 01:01 PM
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in the 1990 owners manual it is on page 198 and 199. in the 1992 owners manual it is on page 170 and 171.

Devon
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