Going Downhill.

[deezeejoey]

Okay It's just a question I've always been wondering and never found a real answer to. I hear both sides.

Is it okay to Shift down in your car when going downhill?
(now that i have a car with Overdrive) is it okay to turn off overdrive when going downhill to slow your decent?

[papariccardo]

Originally Posted by deezeejoey

Is it okay to Shift down in your car when going downhill?

Both sides? One side is wrong. Not only is it OK, it's advisable. You will gain a lot more stability, therefore be a lot safer. Whats worth more, the life of you & your passengers, or the car? OD on/off is a button for that very reason - feel free to use it. Same going uphill, less strain on the motor in 3rd than OD. I have manually shifted auto trans ever since I started driving, gear position is a major player in vehicle stability.

Also, remember this car is a Toyota, not some Chev or Ford. Much more reliable, much better gearbox.

[deezeejoey]

cool thanks, some people told me that it was bad for the transmission

[eurohazard]

If you're doing 125 mph, I wouldn't drop it into 3rd or anything like that. But I very often downshift at reasonable speeds in traffic if I don't feel like hitting the brakes. (I wish I had a 5 speed manual!)

[TMetalMan]

Originally Posted by eurohazard

If you're doing 125 mph, I wouldn't drop it into 3rd or anything like that. But I very often downshift at reasonable speeds in traffic if I don't feel like hitting the brakes. (I wish I had a 5 speed manual!)

It is my understanding that you should not use the engine as a brake when you are running with a manual tranny. The reason being that the clutch will wear in the opposite direction it was made to, which will cause it to wear out faster. But I could be wrong, as I have yet to own/drive a car with a manual tranny.

[nitehawk55]

Originally Posted by TMetalMan

It is my understanding that you should not use the engine as a brake when you are running with a manual tranny. The reason being that the clutch will wear in the opposite direction it was made to, which will cause it to wear out faster. But I could be wrong, as I have yet to own/drive a car with a manual tranny.

Total hogwash

[deezeejoey]

Well as far as speeds, it's a big, long hill.
the speed limit on it is 35 mph. but coasting you can easily get up to 80 MPH
So i'm talking about down shifting at about 55MPH

Originally Posted by papariccardo

Also, remember this car is a Toyota, not some Chev or Ford. Much more reliable, much better gearbox.

I used to drive a dodge, and i think we all know their rep with transmissions. I had to get mine replaced in the shadow last year. I got lucky tho. got a great deal. Refurbished tranny installed for $600.

[papariccardo]

Originally Posted by TMetalMan

The reason being that the clutch will wear in the opposite direction it was made to, which will cause it to wear out faster.

This may be true (never heard so before tho), and certainly you would expect a little more wear in an auto as well. Not enough IMO to justify not downshifting. From a safety/ performance point of view, being in the right gear for the condition outways any such constraints. I drive a 400+ hp car on the road and track, and use the clutch constantly. My auto beater Camry also gets plenty of downshifts as needed, & it won't shift down if you are travelling too fast for the selected gear anyway. OD on/off is the most common switch I use in my Camry, after indicators. That hill you speak of is a classic example of when to switch OD off.

[ghettosled]

if i need to slow down going down a hill i just use that big pedal on the left. i would rather wear the brakes down than give more wear on the engine and tranny.

[TMetalMan]

True, but if you ride the brake all the way down a long hill, there's a chance you could warp your rotors from too much heat. For an auto, I think a combination of being in a low gear and using the brake to get down a hill is the best option.