Yoyodyne

Greetings all!
The question I put before you today is this: Is it reasonable to expect Reverse gear alone to hold the car motionless on a steep grade?
The specifics are these.
Today I was in the process of parking while facing downhill on pretty steep hill. When I took my foot off the brake after shifting into reverse, and before giving it any gas, I felt the car creeping forward down the hill. At first I thought I had mistakenly shifted into Neutral, but I was definitely in Reverse. I tried it several times and was able to repeat the problem.
Now I would never expect the curb idle speed to actually move the car up that grade, but I did expect that the car would not roll forward. I can't recall this happening with any other car I've owned, but perhaps age is playing tricks with my memory.
So, ladies and gentlemen of the jury, I put it to you, have any of you experienced this or do I need to pay a visit to the dealer?
Thanks for the help.

EricL

I do know that my 92 Maxima SE Auto would roll down this steep hill nearby when in reverse (similar to what you described).

I haven't tried it in my car (CLS).

AKRY

It's not healthy for a car to hold itself with just tranny... you are putting stress on the tranny, and cause premature/un-necessary wear on the tranny....

Andy Kuo

daverman

Hey yoyodyne, I had the chance to try this out for myself today, and you're right! The reverse gear doesn't prevent the car from sliding forward.

I wonder if it's because the reverse gear is between 1st and 2nd gear ratios. At idle RPM the engine may not get enough torque to the wheels to keep the car from sliding.

Road Rage

Course it is unreasonabve to expect it to hold - that is how a torque converter works - it does not lock up until the fluid in the turbine is moving faster. If the tranny did "hold" at low speed in reverse, the engine would be abovre the stall speed and would die out.

It is best to hold the car with the brake, engage reverse, then release the brake as you accelerate and the tranny "bites".