C280 rolls when placed in park
 

I've noticed that my 1994 C280 (~80,000) will slightly roll, either forward or backwards (depending on the landscape), when I place the car in park. It probably moves about 2-3 inches, but on steep inclines or declines, it can be quite a jolt. Any advice on where to start looking?
Thanks!

This is normal for a MB transmission.

It takes a little bit of roll for the parking brake pawl to engage into one of the windows that holds the car in place. If the rolling is a problem, use the parking brake.

Thanks for the quick response Ali. That's the answer I wanted to hear.

COnfirmation = Normal.


:eek: ;)

This happens on all auto's, nothing to worry about

Parking Brake...
 

All of my friends think that I am crazy, but I alway set my parking brake before putting any of my cars (or truck) in park. I do it to keep any additional stress off of the driveline, it works hard enough going down the road.

Be warned, if you have not use the parking brake in years it might be a little sticky, but should come around with regular use, or you might need to lube up some cables. This is why I only set the parking brake on my cars...

Parking break a good habit
 

My wife put her van in park while it was running to talk to a repair man who just arrived at the house. Actually, she thought it was in park, but was still in reverse. The van door was almost taken off as the van backed up and clipped the repair guy's van. It then continued backwards until is ultimately hit my son's car, which thankfully kept it from rolling over a 5 foot high rock wall down into a swail in the woods next to my house. It was the first three car accident the investigating policeman had ever seen in a driveway.

In short, use the parking break.

JCD

I also use my parking brake, but sometimes park without it. It rolls for a couple inches until the pawl grabs. Happens on both our current MB's.

Normal.

After reading the above post, I think I'll become religious about using my parking brake.

Using the parking brake is a good idea. My friend's suburban has 110k miles on it, and his family parks it on a very steep driveway. Before 80k miles, they would never use the parking brake, and they had to put in a new tranny 3 times. After 80k, they have been religiously using the brake, and the tranny is running strong. Using the brake takes unnecessary strain off of the tranny, and, its the only thing they bother to teach you in driver's ed....

How really does this effect the transmission? I thought it basically only affected the parking prawl (unless the car was hit when in P)?

I know that when on a hill and Park, is engaged, and then disengaged back into gear, a loud clunk is noticed... is this that bad for the trans?

The parking brake mechanism on an auto tranny works by a metal rod (the parking brake pawl) moving out into a cylinder with recesses in it (windows) and falling into one of the recesses and thus preventing the car from rolling. This setup is towards the rear of the tranny and effectively locks the output shaft stationary in relation to the transmission housing. This is why the cars rolls a little bit, the car and output shaft of the tranny have to move before the pawl can find the next recess to fall into.

That is so true, if ever on a hill, always use the handbrake...and put this on before engaging park, thus there is no strain on the box, also it makes doubly sure that when you get back to you car, it isnt at the bottom of the hill in a pile up!