ShaneN.

Is it ACTUALLY bad for the car to shift it to neutral and then back to drive. Likely for the purpose of free revving the motor, but that's a whole 'nother topic.

Second, can you go to manual mode without ggoing to a complete stop?

CoolBDPhenom03

1) I don't see a problem with it. You can do that in a manual car just fine without any issues (but there, you'd have to rev match).

2) Technically, yes. Recommended? That's a grey area. I toggle between the modes and it's fine.

ShaneN.

I know that free revving a motor in neutral can be bad since there is no load on it, but that's not what I"m asking. I'm just curious if going from drive to neutral or in the opposite direction is bad. I was just watching a c63 exhaust video on youtube and the owner shifts to neutral while coasting to let us hear the car and in the comments I read that someone said going to neutral from drive and back to drive without being stopped is bad for the car. That's not something I've ever heard before.

The second question is just something I've read on here, that you aren't supposed to switch to manual mode without stopping the car, that seems stupid. The car I'm driving had triptronic or whatever and sometimes I'll want to manually shift when I'm bored or I'll want to go back to automatic mode and I never pull over to do that. That just seems silly.

I'm assuming it's fine to go from C to S, though?

gthal

For #2 I say no problem but I'm not a MB engineer. The tranny is electronically controlled. If changing modes while moving was a problem the car would not allow it to occur. A large portion of owners would nor read the manual or think twice about doing this. If it would harm the car MB would not let the car do it or else there would be lots of cars with problems in for service. Just my opinion.

Fung63

i play around with C S and M modes all the time and have no problems. Sometimes I'm driving along a street and feel that a little M action is required

CoolBDPhenom03

Some tranny problems may be coincidental or they may be caused by improper shifting, but as it remains, there is no authority on this board who can definitively tell you that toggling between driving modes is good or bad.

With that said, I'm with gthal's thinking. Generally, I'm completely off the throttle when I changes modes or shift into N for revving. I know our cars are smart, but I think that's the "proper" thing to do in case it is bad.

ShaneN.

I'm kind of back and forth between a c63 and a manual cts-v. I want the cts-v mostly because you can get it in manual but coming from a corvette my whole idea this time was to get something that is better to daily drive but is still not losing any fun factor. I really wanted to go auto but not being able to shift to M mode when I want to might play into decisions.

CoolBDPhenom03

Driving where I drive (all over the Bay Area and frequently in SF) having a manual would be a biatch. Have you seen some of those hills? Let alone trying to parallel park on them? I could do it, but it would be waaaaay more work.

Btw, here's another thought. If we weren't supposed to change from C to S to M on the fly, why can we touch the left paddle and convert C or S into a manual-like mode? Then hold the right paddle to switch back to full auto?

cyberorth

1. Transmissions rely on gears to move in order to maintain proper lubrications. Neutral for a short period should be ok.
2. I avoid switching while hard accelerations and while shifting. Usually do it while coasting. You would have heard something on this board if this created any issues as gthal said, not everyone follows the instructions.

ShaneN.

That seems more acceptable, and sensible.

VaclavSV

I will be driving (even at highway speeds) switch to N just to rev the engine then go back! I have been doing this for the past year and have never had any issues!! As long as you are just pressing down and releasing you should be fine....dont hold the pedal down while it is in N!

VaclavSV

I should have mentioned this.... I only switch after my foot is off the gas! Then switch, then depress, then release, then switch back!

SonnyakaPig

When you do that, you're not going into Manual mode, you are just able to manually change the gears. Manual mode has different programming than C and S mode. And S mode has different programming than C mode.

You'll notice that when you change the trans mode while driving, you can feel a slight but noticable mechanical change of some kind underneath the car. I don't know what that is.

I also agree that if it was bad for the car to change trans modes on the fly, the computers wouldn't allow you to do it, but considering I can feel this slight mechanical movement under the car when I try it, I can at least imagine there is some reason that it's recommended to pull over and change modes when the car is not moving.

VividRacing

You're pressing a button and there is a computer in place to make sure you don't do it at a bad time that would harm the transmission or engine. I don't see why there would be any issue unless you go into too low of a gear at a high speed. I don't even think the car will let you do that (haven't driven one so I'm not sure)

SonnyakaPig

Changing trans modes doesn't change gears. It's just a programming change that affects shift speed and other things that I notice like power, exhaust volume, rpm pick-up.

VividRacing

Oh then why is anyone worried about it?

SonnyakaPig

Probably just because the manual makes a mention of it being preferrable to stop the car before changing trans modes. But, the car will allow you to change modes on the move, so no one really seems to know why the manual says that.

VividRacing

That is interesting, my guess would be that they don't wont someone to switch it and get surprised by a sudden shift or something caused by changing modes but who knows.

SonnyakaPig

Just guessing here, but perhaps line pressure is affected by changing modes. So, maybe AMG doesn't want you to mess with that while you are moving and pushing the car. I assume there is no problem with driving softly and changing modes, but perhaps when you are really pushing the car and the car is about to change gears at high rpms and then you switch modes, there can be some cause for concern. And to avoid this, MB just says, don't do it in general, even if it is okay to do when there is minimal load on the car.

b16

I change modes all the time while driving. I'm only ever in C or M mode, depending on traffic/mood.

khmergod

I only change modes while at red light. Stationary.

SonnyakaPig

Out of curiousity, why don't use S mode? Personally, it's my favorite mode to drive around in.

b16

I guess because I've spent my entire life driving a manual. When I'm driving in auto mode it is really just relaxed/cruising. When I feel like having fun in the car, it is Manual mode. I just never saw much use for S mode.

SonnyakaPig

Ah, makes sense.

Cavu

The only time I make sure to avoid switching modes is at under about 10mph. Since C mode remains in a higher gear, if you switch to S at slow speed I've had it gear down pretty low and it's not a great feeling. I think it's probably that it's switching into 1st gear even though I'm still rolling.