Anyone ever heard that shifting an automatic tranny while the vehicle is in motion causes damage? Just something I overheard and wanted to know if it was true.

No it wont hurt it. Some of the new cars are designed to be shiftable automatics. The acura tl for example:


The 2004 TL is available with an automatic or manual transmission. A sophisticated 5-speed Sequential SportShift™ automatic transmission shifts with grace, or, with a quick flick of the lever into the shift gate, you can upshift and downshift for semi-automatic operation. For those who insist on calling the shots, you'll want the close-ratio, short-throw 6-speed manual transmission, which features a Limited Slip Differential (LSD) for enhanced traction during acceleration, and a Dual-Mass Flywheel for smoothness and control. The Grade Logic Control System minimizes "gear hunting" that other transmissions can encounter on steep roads and downhill stretches.

yeah shift it into reverse while in forward motion. It helps the bearings on the torque converter.

shouldn't do too much damage, ive shifted my old car into D and D2 while it was moving. I havent noticed any problems....

Shifting to R when going forward, or shifting into D when going backwards is just fawking dumb in an auto.

However, using the O/D/2/1/ to shift is a very general occurance, and is often used to slow yourself when going down a hill, the same as you would downshift your manual, or use an exhaust braking kit....

Originally posted by farmer_J
Anyone ever heard that shifting an automatic tranny while the vehicle is in motion causes damage? Just something I overheard and wanted to know if it was true.

Its better to manual shift the transmission than letting it shift itself actually.

been shifting up and down while on the fly for years without any problems.

Originally posted by whitefish
Shifting to R when going forward, or shifting into D when going backwards is just fawking dumb in an auto.

However, using the O/D/2/1/ to shift is a very general occurance, and is often used to slow yourself when going down a hill, the same as you would downshift your manual, or use an exhaust braking kit....

Ditto:D

I would rather replace a set of brakes, than be downshifting to slow your self down to stop. brakes are cheaper than the wear on yer tranny. i dont think that you are truly correct when you say that its better for the trans by manually shifting it. more wear, line pressure, harder shifts,engine rpms etc etc etc are mostly related to manual shifting.

dont shift into p or r while in d or in any combo
leave it in d when u are cruisin
manually shift when needed while towing or racing
easy enough?

if you're not gonna shift your auto in motion.. then when would you shift into 3rd or 2nd? when you're at a stop? what's the point?

Originally posted by whitefish
Shifting to R when going forward, or shifting into D when going backwards is just fawking dumb in an auto.

However, using the O/D/2/1/ to shift is a very general occurance, and is often used to slow yourself when going down a hill, the same as you would downshift your manual, or use an exhaust braking kit....

i hope you didnt think that i was serious.

And its not "better" to shift gears in an automatic.

Originally posted by synds9
if you're not gonna shift your auto in motion.. then when would you shift into 3rd or 2nd? when you're at a stop? what's the point?

No, if you wanted to shift your auto, then you would start out in 1st, then 2nd, and so on. Theres not any point really unless you think your car would go faster that way or your going up a steep ass hill.

You guys have got to be kidding me! Just how newbie is this section getting are you all so desperate to get your post count up that you would actually tell a person not to shift into park or reverse while driving? If they dont know that they dont belong behind the wheel.

As for shifting an auto yes it is recommended especially on long decents to slow the vehicle down. I am not saying that at 60 you drop into second I mean to keep your speed down so you dont burn up your brakes. Your tranny will do just fine getting a little warm if you ride your brakes the whole time you have a chance of them going out.

Again modern cars are designed to be shiftable automatics, so why would there be ill effects?

Originally posted by Halogrinder
I would rather replace a set of brakes, than be downshifting to slow your self down to stop. brakes are cheaper than the wear on yer tranny.

manually shift when needed while towing or racing
easy enough?

I don't "downshift" to brake... It just makes more sense to be in 3 down a hill and staying @ 55 then be in OD and squeezing the brakes the entire way.

Manually shift when "racing" in an automatic... gee, that's NEVER been talked about before --- if your transmission already isn't shifting at the most power-gaining points when you're flooring it, you've got problems.

Originally posted by KingTJ


i hope you didnt think that i was serious.

And its not "better" to shift gears in an automatic.

Nope, I just wasn't sure what the initial question meant, so I clarified both points.

I never said it was "better".

Originally posted by whitefish


Nope, I just wasn't sure what the initial question meant, so I clarified both points.

I never said it was "better".

I know, you didnt say that... braxton357 said it.
i was just making sure you didnt think i was serious about shifting from R to D while in motion.

Downshifting gives the driver A LOT of control over the vehicle. You slow down far more progressively and smoothly than braking. Also, downshifting will improve your braking, because it won't let your wheels lock up when braking, and you get more vaccuum to help assist you braking.

So you get your back dirty and change your clutch every 80K miles vs every 100K miles... Scary! :rolleyes:

Originally posted by Mikel
Downshifting gives the driver A LOT of control over the vehicle. You slow down far more progressively and smoothly than braking. Also, downshifting will improve your braking, because it won't let your wheels lock up when braking, and you get more vaccuum to help assist you braking.

So you get your back dirty and change your clutch every 80K miles vs every 100K miles... Scary! :rolleyes:

Its faster and cheaper to change brake pads and rotors vs trannies. My $.02

The extra safety and driving control is worth it to me.


Originally posted by Otto Man


Its faster and cheaper to change brake pads and rotors vs trannies. My $.02

Originally posted by Halogrinder
I would rather replace a set of brakes, than be downshifting to slow your self down to stop. brakes are cheaper than the wear on yer tranny. i dont think that you are truly correct when you say that its better for the trans by manually shifting it. more wear, line pressure, harder shifts,engine rpms etc etc etc are mostly related to manual shifting.



Thats not true, It DOES make higher line pressure, quicker shifts, and at a higher RPM where there is more power, but the fact that it shifts harder means that it is wearing the bands less. Just like if you were to slip the clutch instead of just let the fawker out. What you don't want to do is shift into neutral while you are driving, and you don't want to tow in OD. Also, modern transmissions--even most old transmissions--will not let you shift into R or P while in motion, they also wont let it downshift to a lower gear until you are going slow enough.:rolleyes:

Originally posted by braxton357


Thats not true, It DOES make higher line pressure, quicker shifts, and at a higher RPM where there is more power, but the fact that it shifts harder means that it is wearing the bands less. Just like if you were to slip the clutch instead of just let the fawker out. What you don't want to do is shift into neutral while you are driving, and you don't want to tow in OD. Also, modern transmissions--even most old transmissions--will not let you shift into R or P while in motion, they also wont let it downshift to a lower gear until you are going slow enough.:rolleyes:

so if i am going like 60mph in my 2000 GT, why cant i go from Drive to Neutral, then back to Drive? even tho theres no point.

Thanks for the replies folks. Good discussion. BTW, I had to ask this question to find out if anyone had ever heard this "rumor" before. My girlfriend and I had argued over it and she said I couldn't shift it while moving. I always have though and havn't had any problems.

Originally posted by braxton357


Thats not true, It DOES make higher line pressure, quicker shifts, and at a higher RPM where there is more power, but the fact that it shifts harder means that it is wearing the bands less. Just like if you were to slip the clutch instead of just let the fawker out. What you don't want to do is shift into neutral while you are driving, and you don't want to tow in OD. Also, modern transmissions--even most old transmissions--will not let you shift into R or P while in motion, they also wont let it downshift to a lower gear until you are going slow enough.:rolleyes:



U can be the 1st to stick in in park at 60, ill do it after you.


i still like arguing with you fawker

Originally posted by whitefish


I don't "downshift" to brake... It just makes more sense to be in 3 down a hill and staying @ 55 then be in OD and squeezing the brakes the entire way.

Manually shift when "racing" in an automatic... gee, that's NEVER been talked about before --- if your transmission already isn't shifting at the most power-gaining points when you're flooring it, you've got problems.



ONCE again, brakes are cheaper than transmissions.


if you just punch it in drive, the trans is normally expecting a normal start, has to drop to first, etc.etc. its wasted time.

if i manually shift my lightning on the 1/4 mile, i gain 2 tenths.

my truck wants to start out in second if it can during normal white man driving.