Am i right in thinking that the later jtd/multijets had 6 speed gearboxs, Is it possible to retro fit them onto a Mw jtd 115 and would there be much gain in doing it. Anyone else done this as i am just thinking from a fuel point of view.
Technical 6 speed gearbox
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Technical 6 speed gearbox
This is certainly true of mutijets although I'm not absolutely certain if the 150 comes with 5/6 speed (the early 140 did).
Absolutely so point in changing even assuming it was feasible :shakehead:
If you want good fuel economy then drop your speed - it's as simple as that
70mph gives significant improvement over 80mph
60mph is the most effective speed but a real struggle I know
Oddly enough it's the sustained high speed, like on a motorway, which is the killer. One of the great joys of the JTD is that you can take the back roads with short bursts up to 3 figure speeds but provided your average is a lot lower (say 60) then you can still return impressive consumption
Absolutely so point in changing even assuming it was feasible :shakehead:
If you want good fuel economy then drop your speed - it's as simple as that
70mph gives significant improvement over 80mph
60mph is the most effective speed but a real struggle I know
Oddly enough it's the sustained high speed, like on a motorway, which is the killer. One of the great joys of the JTD is that you can take the back roads with short bursts up to 3 figure speeds but provided your average is a lot lower (say 60) then you can still return impressive consumption
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This is certainly true of mutijets although I'm not absolutely certain if the 150 comes with 5/6 speed (the early 140 did).
Absolutely so point in changing even assuming it was feasible :shakehead:
If you want good fuel economy then drop your speed - it's as simple as that
70mph gives significant improvement over 80mph
60mph is the most effective speed but a real struggle I know
Oddly enough it's the sustained high speed, like on a motorway, which is the killer. One of the great joys of the JTD is that you can take the back roads with short bursts up to 3 figure speeds but provided your average is a lot lower (say 60) then you can still return impressive consumption
Of course, I'm guessing your meaning in km/h
I know what you mean though about motorway speeds. If I'm doing around the motorway limit or lower, I'll average a fair few miles per gallon more than if I'm going some miles per hour faster. I saw that on my 7 and a half hour drive to Norwich a year around 2 years ago, where the Lake District was just blur
Still though, managed to get well over 500 miles out a full tank
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All Diesel Stilos designated as 150 (so that's the multijet) came with a 6 speed box, the 120 didn't and as far as I know no 140 came to the UK.
I don't think it's (the 6 speed box) interchangeable with the 115/120 engine Pity, I can see the benefits of a 6 sppeder to make the most of the torque, especially having driven my sisters (ahemmm) Vauxhall Astra SRI 150 diesel.... quick..... very quick motor that
I don't think it's (the 6 speed box) interchangeable with the 115/120 engine
Pity, I can see the benefits of a 6 sppeder to make the most of the torque, especially having driven my sisters (ahemmm) Vauxhall Astra SRI 150 diesel.... quick..... very quick motor that 
