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I just bought my 06 DC taco w/ trd off road package and auto tranny a couple months ago and love it so far. I have always had manual transmissions in my previous cars and i am so use to down shifting and using engine braking upon deceleration. My question is are there any negative side effects to manually shifting my auto tranny on a regular basis? I know if i wanted a manual i should have gotten one, but i got such a good deal on the truck since it ones one of the only 06's left on the lot that i decided to give the auto a try. Any input is appreciated, Thanks
 

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hell i do it everyday...upshift and downshift...just watch the "shift points" it says something in the owners manual...
 

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Well, I can't speak on whether or not it's "good" for the transmission, but I was tought to downshift ("engine brake") in vehicles when going down steep grades. For instance, if I were to try to go down Old Priest Grade (Tuolomne County, CA) without downshifting, there is a significant risk of my brakes catching fire by the time I get to the bottom! :eek: I wouldn't recommend doing it every time you come to a stop sign, but I've never had any ill effects from using it intelligently.

...oh, and this post may want to be re-posted in "newbie tech." :)

-Radar
 

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I live in a very hilly area, so I downshift on the way down every day. No probs with 18k on the clock.
 

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I wouldnt do it upshifting unless your racing a F-150 ;)
but down shifting, keeping it around 3000 RPM, to slow down doesnt hurt anything and can help save your brakes. Using the engines compression downshifting puts as much stress as excellerating so no biggy. :2cents:
 

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I know my dad has done it on his vehicles for years with no problems. my first car was an automatic 79 BMW 320 that I got in 96, he had been shifting that thing since it was new, and I learned to shift it as well. No problems.
 

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High speed downshift braking causes plug fouling and oil contamination....like phoenix said, keep the revs in reason.
You guys do know that the computer won't let you downshift if it's going to over rev, don't you?
 

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You guys do know that the computer won't let you downshift if it's going to over rev, don't you?
No, I wasn't aware of that because I've never downshifted and had an override occur; but it's to prevent engine "overspeeding" which is another matter altogether.

I never did understand all the technobabble on the subject, but it deals with ring float with direction changes in piston travel; relative pressure differences in the combusion chamber and crankcase; idle mixture shots at high revs; and, other such crap. Oil gets sucked by the valve seals into the combustion chamber and unburned fuel goes into the pan.

It doesn't necessarily cause damage but can cause poor idle and it puts you into "rough service" category where oil changes are concerned.
 

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No, I wasn't aware of that because I've never downshifted and had an override occur; but it's to prevent engine "overspeeding" which is another matter altogether.

I never did understand all the technobabble on the subject, but it deals with ring float with direction changes in piston travel; relative pressure differences in the combusion chamber and crankcase; idle mixture shots at high revs; and, other such crap. Oil gets sucked by the valve seals into the combustion chamber and unburned fuel goes into the pan.

It doesn't necessarily cause damage but can cause poor idle and it puts you into "rough service" category where oil changes are concerned.
Hate to disagree with you. But if that were the case, you would never see a diesel running a jake brake. Plus when you downshift, the TPS is not seeing an open throttle, thus does not feed the same amount of fuel to the engine based on lack of need. The truck's computer controlled trans also knows when you are coasting VS accelerating and adjusts accordingly.:2cents:
 

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Hate to disagree with you. But if that were the case, you would never see a diesel running a jake brake. Plus when you downshift, the TPS is not seeing an open throttle, thus does not feed the same amount of fuel to the engine based on lack of need. The truck's computer controlled trans also knows when you are coasting VS accelerating and adjusts accordingly.:2cents:
Disagree all you like....Jake Brake opens the exhaust valves on compression stroke at point of mixture ignition, dissipating all energy/unburned fuel into the exhaust system....apples and oranges.

Your engine is still under load and you're not coasting on a downshift; you're coasting if you throw the tranny in neutral. Do a hard downshift, shut your ignition down, and index your spark plugs.

One of the reasons race cars eat spark plugs.

BTW....been meaning to ask. Do the Elliotts still live at 10 Ranchview Road?
 

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If you are shifting as if it were a manual tranny, then you chose the wrong mechanism. Some people don't use an automatic like an automatic and that is bad. Doing it occassionally isn't bad, but don't do it unless there is a need.
 

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If you are shifting as if it were a manual tranny, then you chose the wrong mechanism. Some people don't use an automatic like an automatic and that is bad. Doing it occassionally isn't bad, but don't do it unless there is a need.
My Truck was wrecked and in the Body Shop for 48 Days, after about a week of driving a rental I started to go crazy as it was sooooooo boring, I started shifting it manually just for something to do.
 

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My Truck was wrecked and in the Body Shop for 48 Days, after about a week of driving a rental I started to go crazy as it was sooooooo boring, I started shifting it manually just for something to do.
It's okay to do that to rental vehicles. :)
Before I bought my truck I rented the most similar truck I could ('05 TRD w/AT vs '06 TRD w/MT) and took it to an offroad park. I actually left the ground in that thing...glad it wasn't mine :D
I'll never buy a rental automobile :eek:
 

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Disagree all you like....Jake Brake opens the exhaust valves on compression stroke at point of mixture ignition, dissipating all energy/unburned fuel into the exhaust system....apples and oranges.

Your engine is still under load and you're not coasting on a downshift; you're coasting if you throw the tranny in neutral. Do a hard downshift, shut your ignition down, and index your spark plugs.

One of the reasons race cars eat spark plugs.

BTW....been meaning to ask. Do the Elliotts still live at 10 Ranchview Road?
an exhaust brake shuts off the exhaust after the turbo, causing a backup in the exhaust, it doesn't do anything to the exhaust valves. I ran a Banks unit on my turbo diesel excursion, so I'm not blowing smoke out of my ass.:) Yes, downshifting does put some stress on the engine, but it is not seeing the additional fuel or heat (as in the case of a jake brake). I would agree with you if the truck was carburated, but not fuel injected. The TPS tells the computer what to do. The engine is nothing more than a big air pump, just add fuel and combustion. I will not hurt the engine to merely pump air through it by down shifting. I don't know the Elliots, that address is in Rancho Palos Verdes. But my ex wifes parents live at 15 Ranchview rd.
 

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It's okay to do that to rental vehicles. :)
Before I bought my truck I rented the most similar truck I could ('05 TRD w/AT vs '06 TRD w/MT) and took it to an offroad park. I actually left the ground in that thing...glad it wasn't mine :D
I'll never buy a rental automobile :eek:
I am with you, I would NEVER buy a Rental, I was just going out of my mind in boredom driving that car, I was up shifting and downshifting just so I could keep busy.
 
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