WOT in the gear I'm in?

[MancMike]

Hi,

It's been bugging me since I got an auto, but I love it so much it's not put me off.

In a manual, of course, you can go to wide open throttle in any gear, whenever.

In my auto, if I go to WOT, even if I don't go through the kick down button, the car drops gears.

That's fine if I want to overtake, as it drops gears and launches really impressively, but sometimes I just want WOT in the current gear, as it's got decent pull I'm happy with the progress we're making, I don't always want to drop 3 cogs and be launched.

It seems I can go about half way on the pedal (which isn't much pull at all) before it'll start wanting to downshift. If I do quickly blip it to 3/4 throttle, it'll give some nice pull, but then that pull abates while it decides how many gears to drop!

Is this normal? I've tried resetting the pedal with that procedure...

Also I've realised it seems to learn your current driving mood, as if I creep in slow traffic, it gets up the gears faster, so when I touch the gas more, there's no pull. If I'm on clear open roads and am making much better use of the engine, I find it stays in lower gears, so there's more pull available when I do go on the gas...

 

[markmifsud]

I think its normal, at least sounds very normal to me. The box will always try and select the most appropriate gear for the current speed/engine speed/throttle position

 

[Rashman]

This is one of the reasons why manual mode is best.

 

[jotter22]

This is one of the reasons why manual mode is best.

Possibly in a 63.... not necessarily in a 280!

Tony.

 

[MancMike]

This is one of the reasons why manual mode is best.

Yeah, I can't be faffed with that. When I come off the throttle in 3rd for instance, I get huge engine braking, where as in auto, it'll upshift to reduce that.

I haven't got paddles, so I guess that makes it a bit more fiddly to use.

If it's normal I guess I'll live with it.

It's not in 63 league, no, but still, a 3L V6 Petrol and 7G box isn't to be sniffed at, it certainly moves when you floor it. :bannana:

 

[whitenemesis]

Yes, MB autoboxes are adaptive, learning the driver's style. It quite quickly re-adapts but it's noticeable for a few miles.

The autobox will always try and shift to the gear that will best serve the engine, so depending on throttle and engine load it will drop gears to give the most efficient acceleration. Something a manual box (obviously) can't do and it's not uncommon for drivers to slightly labour the engine.

You do know you can influence the autobox shifts by tapping the gear selector left (down-shift) and right (up-shift)? It will only allow shifts that keep the revs within 'correct' limits but if you hold the selector for 2-3 sec in either direction the 'box will change as many gears as possible in one shift.

 

[MancMike]

Yeah, I knew that, thanks. It's just a bit frustrating, as if I hold left, so it'll get to the lowest gear ready to overtake, etc, sometimes it'll rev the engine to 5k rpm to sync, before engaging power again, and that can take a good couple of seconds, then power arrives for all of 1k rpm when it shifts up to the next gear at 6k rpm...

I'd be happier with paddles I think, but that's something for the future.

 

[whitenemesis]

The paddles only mimic the shifter, operation is the same (unless you go for full manual mode)