Just noticed tonight that the gbox on this merc flicks over to Neutral quite a bit if you’re in automatic but not accelerating or braking just letting momentum take you. ■■■■■■? Meant to be like that? First time I spotted it was when I had cruise control on downhill, the retarder wasn’t kicking in as usual then I saw it was in N.
yes itS normal its called ecoroll oh the merc has an exhaust brake its not a retarder
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alix776:
yes itS normal its called ecoroll oh the merc has an exhaust brake its not a retarderSent from my HD7 T9292 using Board Express
my bad, and as for the ecoroll, it’s crap. Lol
Switch it off if you want - there is a switch on the dash labelled “power” ISTR. Pushing the bottom half of the switch will turn off the economy. Push the top and it is in sport mode - tighter suspension, 4x4 splits the power through limited slip diff and top end limit raised… OK power mode just holds gears a little longer for long hills with heavy loads, but we can all dream 
I thought coasting was illegal or at least highly disapproved of, how come if its part of a fancy computer controlled faff, (that will cost far more to fix than any fuel saved over its life when it goes wrong), its OK to free wheel?
Juddian:
I thought coasting was illegal or at least highly disapproved of, how come if its part of a fancy computer controlled faff, (that will cost far more to fix than any fuel saved over its life when it goes wrong), its OK to free wheel?
exactly, had a bit of weight on last night, was coming down a few hills on the m6 (■■■■■■■ has quite a few) and noticed it was “free wheeling”, no wonder it was shooting towards 95kmph plus.
Power button you say? I’ll have a look as I really hate the ■■■■■■ thing.
This is the switch you need, just press the bottom of it and a red arrow will light up on the switch
Yes - power switch - it’s got a picture of a diff/prop-shaft on it I think. Like the one above 
If in eco mode the exhaust brake should come on when you exceed the set limit anyway (approx 96Kph).
gardun:
Yes - power switch - it’s got a picture of a diff/prop-shaft on it I think. Like the one aboveIf in eco mode the exhaust brake should come on when you exceed the set limit anyway (approx 96Kph).
yeah it does, but not before you rocket on towards 95/96kph. Tonight, that’ll be knocked off.
It does the same with cruise - you can adjust how far over the limit/cruise speed you want it to cut in.
Before long it will break down and then you’ll have a chance to read the manual while you wait for a fitter
I’ve never been entirely convinced by the argument behind the Merc/Volvo eco-roll function.
I can see that it helps the truck maintain momentum on a downhill, but fuel is being burned turning the engine over.
Most modern diesels will shut the fuel off in overrun, and not burn any.
So, how does burning fuel unnecessarily help fuel economy?
Interesting to test two identical trucks : one using the function and one without; on an undulating route.
GasGas:
I’ve never been entirely convinced by the argument behind the Merc/Volvo eco-roll function.I can see that it helps the truck maintain momentum on a downhill, but fuel is being burned turning the engine over.
Most modern diesels will shut the fuel off in overrun, and not burn any.
So, how does burning fuel unnecessarily help fuel economy?
Interesting to test two identical trucks : one using the function and one without; on an undulating route.
My thoughts exactly about eco-roll. I would have thought that the weight of the truck alone is enough to keep the momentum going on a downhill without the need for the gears to go to neutral.
If it was that good a system, why doesn’t Renault have the eco-roll function on their version of Volvo’s I-shift? Probably because they don’t see any benefits to fuel economy from it.