Transmission Question

[monteballz]

Maybe some of you will think this is foolish. I've got an 07 GMC Sierra 2500HD. With gas prices being so crazy i've read about people putting thier vehicle's into neutral when going down hills to conserve gas. Obviously I didnt buy the truck to be good on gas but every little bit will help. My question is. . . Is it going to wear the tranny out if everytime i go down a hill i put it into neutral and then put it back into drive when the truck starts to slow down. I've been able to get 18mpg around town and 22 highway doing this. But if its going to have a mechanical downfall then I will stop doing it. any facts on this would be great to know. thanks

 

 

 

-Mike

[95Sierra2500]

I can't think of any actual damage it might cause. You're simply reducing the engine's RPM to idle (and still turning the trans oil pump) without providing power to the wheels. About the only issue I can see is that you won't be able to engine brake (letting the engine help keep your speed down as you come down the hill) and you may end up going through brake pads more often if you need to check your speed. I don't know what the terrain is like around you, but it's pretty impractical where I live as there aren't many hills to be able to do this on.

[cammiller]

This would be pointless. When you are going down hill, and off the pedal, the truck goes into decel mode where the injectors are turned off, therefore using no fuel.