marlinspike

If you have an E350 4matic, could you please test the following:
Go a steady 52mph. Floor it. Do you get 3rd gear or 2nd gear?

Izrud

Will try this later for you. In sport or comfort?

Also worth noting that after i reset my automatic transmission a few days ago, the car feels like it has a completely new gearbox.

Cheers

agm18

3rd gear every time (3x). E350 4M wagon

marlinspike

In Sport, though really it shouldn't matter. In fact, if you don't want to floor it, just try moving the shifter into 2nd gear manually (while your foot is on the throttle holding speed steady, there is a different result that I am not concerned with if your foot is off the gas) and see if it allows it or if it stops downshifting at 3rd.

marlinspike

Ok, so we have this result from my 2007 (after the engine serial number break 2007 though) and your 2006. A friend with a 2008 says his gives him 2nd gear. Trying to figure out if his is a fluke (or maybe a software change).

ps2cho

I have a 2008 can try this weekend hopefullyt

rodneypierce

unlikely its giving him second gear. If it is, it would be pretty far up in the rev range...

marlinspike

That's the point of flooring it. This is the only car I've owned that won't give you the shortest gear you can be in when flooring it, so I'm trying to find why the variation.

rodneypierce

what good is downshifting to 2nd when its going to up-shift to 3rd around 60 mph?

*edit*
I was incorrect, it does go to 2nd and up-shifts to 3rd at 68 mph

rodneypierce

I'll actually go test this in a minute. I just reset my TCU so I'll see what I get. But I'm willing to bet I'll get 3rd. Mine is an e550 4matic but it's the same trans.

marlinspike

I'll be curious to see your result. They do have the same trans but different TCU programming, so it won't really be relevant to the question here, but I'm curious to see how many MBs out there take this lazy-shifting approach. Your redline is lower though, so your shiftpoints will be different. I would be curious to hear how far it will hold 2nd if you floor it from standstill vs what speed it will let you drop to 2nd at if you floor it while already rolling.

rodneypierce

I was incorrect. It does downshift to second (right after TCU reset) and hold it until 68 when it up-shifts to third.

marlinspike

When you say TCU reset, are you talking about the procedure involving the gas pedal or something done with the STAR diagnostic system?

rodneypierce

yes, key to position 2, press gas pedal to the floor for 15 seconds, key to off position, release pedal and wait 2 minutes.

marlinspike

I've done that before, but just in case tried it again. No change to this aspect of shifting.

Toastr

I may be off a bit, but I was under the impression that triggering the kickdown will downshift 2 gears, while regularly flooring it (but without pressing the kickdown button down) will downshift one.

If that's the case, then your definitions of "flooring it" may be different. Are you pushing it till it pushes no mo' or are you giving up as soon as you feel resistance?

marlinspike

The kickdown should downshift to the lowest gear the TCUs calibration will allow at that road speed. Flooring it shy of the kickdown will do any number of things, determined by adaptations as well as realtime measured factors. The question I'm trying to find out is if there are different TCU calibrations for different years (enabling one to change software to one that is more aggressive).

Izrud

Downshifted to 2nd for me on first try, 3d on second try. Trans in this car is definitely not the highlight of the car - I would enjoy it for what it is: a great highway cruiser. Additionally even if there was different TCU calibration for different years, how would you really find out? This "test" is not really going to give you any definite results. Finding out a shop that can do anything about sounds twice as hard. Maybe look into a spring booster if you are not satisfied with the way your car responds or try a ECU flash - both established options of adding a little bit of sportiness to the platform.