My mate drives a six month old Volvo FH 12 with an ‘I’ shift gearbox.
He continually complains about the vehicle’s gearchange being ‘useless’.
Having driven the motor a few times myself, I’m inclined to agree!
It hangs on to the lower gears and changes in the higher gears too soon.
It’s a real nuisance,despite the local dealer’s attempts to fix it.
I have driven slightly older Volvos with ‘I’ shifts and I rated these as excellent-probably the best CAG gearboxes that I have encountered.
I’ve been told that there is a new gearbox behind the 13 litre engine and wondered if any of you readers have suffered similar problems with newer motors? I’ve been told that a sister truck performs equally badly. 
Mike is it your ‘assumption’ that it changes to quick/slow or do the fuelfugures reflect this? I ask because a box/engine does not always perform best to the drivers feel/ear contrary to what proponents of the ‘i wanna feel a real gearbox’ will tell you. Is the rev counter mainly in the green?
i have had problems with them on FM9 units. a 53 plate trying to pull away uphill in 4th and it kept stalling so i had to manually override it to get going
i also had a 55 plate lose its transmission during manouvreing. wouldnt select a gear so i had to switch off and on again
apart from these, i think its great and i dont like autos
The gearbox chooses the most economical gear , economical being a higher gear then what you would probably normally choose .
I’ll take it your mate likes to accelerate quite rapidly away .Press the E/P button on the top of the box so that P is showing on the display screen , the perfectly fine best auto box i have ever driven volvo will now accelerate away using more gears and higer revs and should keep you happy .
Also use this function before you hit a hill when you are loaded and it will change down using higher gears to keep you trucking up the hill .
I drive a 480 and i loikes em , i thought the 460 was good as well .Not much cop in a 420 but hey after a 480 and a 460 you are spoilt 
Also bear in mind that there are different software options available to operators.
In other words, two similar looking trucks with the same engines may have very different driving characteristics.
My 420 ran a version which was geared for economy. Sounds to me that your mate has this too.
I think that if he just lets it get on with the job it will be OK. Forget what noises the engine is making - just watch the rev counter.
He won’t be winning any races uphill, but he should be turning in decent fuel figures.
Bloody marstons thrashing around town 
Cheeky git goseley estate is the bronx .
Anyway i’m nearly woodville where i live so i,m a pit posher
Not seen you for a while either .I’ve waved at a couple of Marstons trucks .
Anyway whats all this flash of yellow malarky , i came out of stretton at 4am the other morning unit only ,when one of your lads was on the roundabout by ian simpsons , i put my foot down and rocketed upto 40 , by the time i got to pentagon he was right up my backside , don’t tell me he wasn’t on the limiter coming off that roundabout .
Tell yer you marstons boys are reckless , you will never see one of our NDC shunters driving around like that
racing line through the roundabout thay way you dont need to slow down
Thanks for you replies.
The FH in question doesn’t like changing manuallly much either, it doesn’t matter whether it’s warm or cold.
It seems to have a mind of it’s own The computer doesn’t flag any specifiic faults up regarding the gearchange, there doesn’t appear to be any software upgrades either, unless the wrong software has been installed in he truck?
Fuel consumption at about 8.2 mpg on a regular easy run, oler units doing nearer 9mpg
(now wheres the smiley for sticking two fingers up