Driving Style and Autobox Wear

[television]

Tch Tch... thats a bit underhanded isnt it Eric?????

ML - mine, no problem re:hill hold, so might be due to age on your Kebo. Change the oil as a starter.

ML's RULE OK ... especially Mark 1 and pretentious Mark 2's ...... definitely not the queer Mark 3's

Mine though is under 20k miles yet it will run back, the last one with the same box did not.

We had a thread on this a while back, and some cars in the same range did, others did not, not to important is it reaaly

 

[panason1c]

My ml roles back, which felt wrong when I first drove it, being use to 4 speed ZF box from landrover which doesn't role back even on 1 in 1 hill
Kevin

Mine does too!...........the original tranny did and now also the 'new' recent replacement tranny (cannibalised from a written off 1,000 miler)......i previously read somewhere on another thread that this was normal on these boxes.

 

[Blobcat]

I Have A Problem With The Auto Box On A 2006 reg CL500. When Stopped On Incline The Car Rolls Backwards Unless I keep Revs High. Anyone Had This Problem. Dealer Says It Is Normal. I Have Driven 5 Autos In Last 10 Years And Never Had This Occurs. Comments Would Be Appreciated. Obviosly the box is in D when this happens. Excuse my manners this is first time on..

Hi & Welcome, If this is a 7G box then it may be "normal". I think you are supposed to use the "Hold" function on the brake then accelerate to go rather than just slip it into reverse. I was caught out this week by driving my new 7G box the same way I have driven the 5G. Facing down a hill I selected reverse and it rolled forward which I was not expecting at all. I stopped used the "Hold" function then selected reverse and accelerated backwards. Takes a little to get used to.

 

[eric242340]

Mine though is under 20k miles yet it will run back, the last one with the same box did not.

We had a thread on this a while back, and some cars in the same range did, others did not, not to important is it reaaly

From a technical point of view its very important and after a transmission rebuild its one of the most important road test items. It tells us a lot about the internal workings and how they are performing. To the everyday driver/owner it may not seem that important.

 

[television]

Hi & Welcome, If this is a 7G box then it may be "normal". I think you are supposed to use the "Hold" function on the brake then accelerate to go rather than just slip it into reverse. I was caught out this week by driving my new 7G box the same way I have driven the 5G. Facing down a hill I selected reverse and it rolled forward which I was not expecting at all. I stopped used the "Hold" function then selected reverse and accelerated backwards. Takes a little to get used to.

This could also be the difference on my car as this one has tiptronic, so just a software issue.

I can understand that the hold functions take a little getting used to, it took me a while to realize the car would not go with the slightest touch on the brake pedal.
Did it take long to feel safe using these new things ?

 

[Blobcat]

This could also be the difference on my car as this one has tiptronic, so just a software issue.

I can understand that the hold functions take a little getting used to, it took me a while to realize the car would not go with the slightest touch on the brake pedal.
Did it take long to feel safe using these new things ?

Brake hold I have pretty much got used to and like the convenience. The only time it can be a pain is when maneuvering around the drive, I'm used to stopping then selecting reverse and letting off the brake and going back without the application of the accelerator. If I'm not careful I press the brake a little too hard and put the "Hold" on this then means I have to use the accelerator to reverse.

I will have a read of the manual and see what it says regarding hill starts.

 

[whitenemesis]

I do what I want and don't give a toss. If something's going to wear in each situation, then surely a variety of situations will save total wear on some components and lack of wear on others. Let's even out the wear, forget about the negligble fuel cost increase, if any, and just enjoy life.

If stopped at lights, D and footbrake.
If stopped for more than a few minutes, N and parking brake.
If stopped and getting out of the car, P and turn off, take keys, phone, cigarettes, wife if she's with me , and concentrate on what I'm doing , where and why. Forget about car until I need it again.

Life's too short for worrying, enjoy your car, enjoy your driving, enjoy life if you got one.

I like this answer!

This is getting far too anal.

 

[daveenty]

Personally (stress that bit)

Set off in the morning. Go to where I'm going. Irrespective of where, traffic, hold ups etc. it stays in D.

Only exception is if I'm in a non moving queue (Motorway accident e.g.)

As Trophy1200 says....life's too short. If it breaks it breaks. Fuel?....going to use that anyway. Another bit won't make a lot of difference to either my pocket or the climate.

Another thing that Trophy1200 said: enjoy life if you got one.

Know exactly where you're coming from there m8 Just got back from enjoying myself....must stop doing that bit (NOT)

 

[whitenemesis]

Personally (stress that bit)

Set off in the morning. Go to where I'm going. Irrespective of where, traffic, hold ups etc. it stays in D.

Only exception is if I'm in a non moving queue (Motorway accident e.g.)

As Trophy1200 says....life's too short. If it breaks it breaks. Fuel?....going to use that anyway. Another bit won't make a lot of difference to either my pocket or the climate.

Another thing that Trophy1200 said: enjoy life if you got one.

Know exactly where you're coming from there m8 Just got back from enjoying myself....must stop doing that bit (NOT)

YEH!!!

 

[psmart]

I've had a brain storm.... Eureka!

My theorem! Mercedes are trying to minimise lost energy (ie. fuel) when the auto-transmission is in D by lowering the revs and power output. There will be a minimum required amount of power/torque into the auto-transmission before all the bands etc are engaged, creating load. This will explain why some do not have the hold feature, as the engine power output will be lower than others, therefore not putting sufficient power into the auto-transmission to engage its workings.

It is a theorem, but will put many of the threads info into context, aka Hibbo and the lowering of revs etc.

 

[television]

I've had a brain storm.... Eureka!

My theorem! Mercedes are trying to minimise lost energy (ie. fuel) when the auto-transmission is in D by lowering the revs and power output. There will be a minimum required amount of power/torque into the auto-transmission before all the bands etc are engaged, creating load. This will explain why some do not have the hold feature, as the engine power output will be lower than others, therefore not putting sufficient power into the auto-transmission to engage its workings.

It is a theorem, but will put many of the threads info into context, aka Hibbo and the lowering of revs etc.

Only snag is that the HOLD feature when it was introduced was fitted to all cars with that breaking system, and the box and ECU are the same as the ones earlier without.

Sure this could explain the rolling back issue with the lower revs / output, also why there is no mention of putting into N when standing in my book

 

[television]

This bit about rolling back, some do ,some do not. The difference of +25rpm is enough to stop it rolling back, tried mine today on a steep hill, (all steep around here) The smallest touch on the throttle stops it rolling back,so that answers that one

 

[eric242340]

This bit about rolling back, some do ,some do not. The difference of +25rpm is enough to stop it rolling back, tried mine today on a steep hill, (all steep around here) The smallest touch on the throttle stops it rolling back,so that answers that one

Its supposed to hold at idle speed and no throttle

 

[television]

Its supposed to hold at idle speed and no throttle

Not really there is no written matter about rolling back, anyway the difference is 25 rpm, hardly an issue or fault

 

[eric242340]

Not really there is no written matter about rolling back, anyway the difference is 25 rpm, hardly an issue or fault

It seems to be an issue for some people, but certainly no fault.

 

[television]

It seems to be an issue for some people, but certainly no fault.

If it is an issue then all people need to do is to ask for the idle to be increased by 25 rpm

 

[psmart]

If it is an issue then all people need to do is to ask for the idle to be increased by 25 rpm

Aaah! But then they waste more fuel.... so they would have to put it in N otherwise the Green Police would bi issuing them a ticket....

My engine idles at 752rpm (according to CarSoft), so what do other 270's idle at?

 

[whitenemesis]

Aaah! But then they waste more fuel.... so they would have to put it in N otherwise the Green Police would bi issuing them a ticket....

My engine idles at 752rpm (according to CarSoft), so what do other 270's idle at?

Mine idles at 650rpm (according to the rev counter), engine warm.
Interesting to see the rev needle jump slightly then fall back as the aircon kicked in and again as the phone connected! The former I can understand but the latter!? :roll:

 

[wireman]

A theory:-
It may be an electromagnetic compatibility (EMC) problem.
The phone's emmited UHF energy may be getting picked up by the some of the cars wiring, upsetting the alternator regulator and causing the reg to think that there is a drop in system volts and compensating by making the alternator do more work which will slow the engine slightly.

This should not happen, the battery may be damaged by overcharging and other parts may get damaged by over voltage.

PS
I now have another reason to reccomend that cell phones are not used in cars.

 

[television]

A theory:-
It may be an electromagnetic compatibility (EMC) problem.
The phone's emmited UHF energy may be getting picked up by the some of the cars wiring, upsetting the alternator regulator and causing the reg to think that there is a drop in system volts and compensating by making the alternator do more work which will slow the engine slightly.

This should not happen, the battery may be damaged by overcharging and other parts may get damaged by over voltage.

PS
I now have another reason to reccomend that cell phones are not used in cars.

I think that you will find that the blip is caused by the cars wake up circuits comming to life while the high speed data check is taking place and no more than that.