6 speed 2.0hdi

[steve_earwig]

DW10ATED ML5T:
1st 12x41 3.58:1
2nd 23x41 1.78:1
3rd 33x37 1.12:1
4th 44x35 0.8:1
5th 51x31 0.61:1
Final drive 16x65 4.06:1
Overall in top: 2.48:1
205/60 r15 circumference = 1912mm
46.26kmh/1000rpm
28.74mph/1000rpm
Which gives 2436rpm @ 70mph

DW10BTED4 ML6CL:
1st 12x41 3.58:1
2nd 23x41 1.78:1
3rd 33x37 1.12:1
4th 44x35 0.8:1
5th 51x33 0.65:1
6th 57x31 0.54:1
Final drive 17x71 4.18:1
Overall in top: 2.25:1
205/60 r16 circumference = 2026mm
54.03kmh/1000rpm
33.57mph/1000rpm
2085rpm @ 70mph

With 205/60 r15 wheels gives 50.99kmh/1000rpm or 31.68mph
or 2210rpm @ 70 mph

Somebody check my maths - My BrAiN HuRtS

[HimBigChief]

For anyone even better at maths, what would happen if you were to swap the final drive gears around too? Also, looking at the ratios, 1-4 are exactly the same on both boxes anyway.

[steve_earwig]

And your starter for 10 is...

I posted these over on the coupé club more than a year back:

ML6CL final drive ratios (all PSA):
14x67
15x67
16x69
17x67
17x71

If they fit...

[Doggy]

Yes, yes.....but wot we want is:-

DW12TED4 / ML5C vs DW12BTED4 / ML6C

@Disco 134mph simply won't cut the mustard, (regardless of country of origin).

Not convinced 1st is shorter - 350+ Nm just begs for summat to shove against.

[steve_earwig]

Yes, yes.....but wot we want is:-

DW12TED4 / ML5C vs DW12BTED4 / ML6C

But that's not what the OP wants

You could, you know, work it out for yourself

Or I will next time I'm bored...

[Doggy]

You could, you know, work it out for yourself

Where did you find the info on ratios?

[steve_earwig]

4HX
1st 12x41
2nd 23x41
3rd 33x37
4th 44x35
5th 51x31
final drive 17x67
overall in top 2.4:1
47.89kmh/1000rpm
29.76mph
2352rpm @70mph



4HT (btw. seems like the same ratios for the lower output HDis)
1st 12x41
2nd 23x41
3rd 33x37
4th 44x35
5th 51x33
6th 58x31
final drive 17x71
overall in top 2.23:1
54.45kmh/1000rpm
33.84mph
2069rpm @ 70mph



with 1912mm tyres
31.93mph/1000rpm
2192rpm @ 70mph

Is anyone checking my maths here? I've no idea if I'm doing this right!!

[jasper5]

My 407 2.0 HDi 136 gives 70 mph @ 2,000/2,100 rpm in 6th gear , so I guess you aren't far off Steve

[trem1]

My 407 2.0 HDi 136 gives 70 mph @ 2,000/2,100 rpm in 6th gear , so I guess you aren't far off Steve

yep mine as well

[steve_earwig]

Cheers guys, I thought it must be somewhere near as it's not obviously insane.

You could, you know, work it out for yourself

Where did you find the info on ratios?

Sorry, didn't see you write this wial i woz doen tha maffs. Umm, it's a sweet li'l thang I like to call Service Box

[Doggy]

Ah, I think I finally blundered into the right page.

Looks about right to me too - with 205/60/15's, I get 49.35 km/30.85mph per 1000 rpm or 2269 rpm @ 70 mph, (do you agree)?

So an ML6 has the same ratios, just an extra one on top. If so, that makes it much more interesting as I didn't really want any closer ratios, (don't think that would suit the engine's characteristics).

So, will it fit?

Where to get one?

[steve_earwig]

Nope, that was my last figure Maybe I got the circumference wrong, what was your figure?

There's bound to be at least one parked near your nearest large airport...

[OdinEidolon]

What worries me is electrics. Can you teach the ECU you have 6 gears not 5? Will cruise work? Will the dials read the right speed?

[DiscoPol]

i clocked my C5 today at 115kph(71.25mph ish) it was doing 2050rpm in 6th and recording 6.4 l/100km quite nicely too

[OdinEidolon]

i clocked my C5 today at 115kph(71.25mph ish) it was doing 2050rpm in 6th and recording 6.4 l/100km quite nicely too

dw12ted4 is at 2250 with that speed and scores 4.8l/100km according to the trip. Today went for a 250km mountain trip and the computer says 4.2l/100km. Beat that (with a faulty injector!).