[sledcrusher]

I was just wondering if downshifting an automatic was bad for it. I didnt think so, but people were telling me it was. Today I was sliding down a hill and the brakes were absolutely useless with these roads ( sleet/snow/slush ), and I shifted into 2nd, then 1st. When I shifted into second, I was probably doing about 25mph, and I know it will push 70+mph in 2nd, and then once I got to about 15mph I shifted into 1st.

Is it bad for it?

 

[dtmmil]

No, thats what you should do at times to keep control of the vehicle.

 

[madcow]

depends on the vehicle. as your engine rpms are low your system pressure is low and you get slippage, that is why the early dodge cummins had tranny trouble, you had power to tow in overdrive but the system pressure got so low the tranny would slip and you had faliure.

going down hill on ice there is slippage at the wheels and more than likely your engine rpms came up as soon as it shifted so there isnt any real chance of slippage in the tranny. alot of trannys wont shift down until you reach a certain mph, so lets say you are at low engine rpm in drive but at a high mph, if you pull the lever into 2nd it might wait until the car drops to a certain mph before shifting down. i would not be scared of doing it, most trannys today are built with a lot of protection in them.

 

[RMK-KING]

Madcow covered it pretty well,it will not hurt anything.

 

[Offshore24]

I do it all the time on big hills pulling the trailer. You want to save your brakes for something rally important. So dropping out of D to 2 will hold your speed down without braking.

 

[pudamobile]

I do it all the time on big hills pulling the trailer. You want to save your brakes for something rally important. So dropping out of D to 2 will hold your speed down without braking.

And as long as the Torque Converter stays locked, you don't have to worry about torching the tranny!

 

[Ugly_old_Poo_kid]

Doing this on occasion shouldn't hurt the tranny.

Doing it all the time, like downshifting a standard, will torch the tranny.