For the last couple of weeks or so, I've noticed the MV6 seems to 'thump' into top gear, when accelerating gently up to national speed limit, and gear changes generally sometimes feel a little jerky.

I checked the ATF level today - it took just under half a litre to top up, which I guess won't make too much of a difference.

What concerns me more, is the noise! When idling, there is a noticible 'whine' or screaming noise, coming from the gearbox. It changes tone a bit with you go from neutral to a gear, but it's definitely there.

I'm thinking - failing pump inside the box? Which would probably explain the rough changes?

I did think potentially blocked filter, but have never seen one blocked before!

Any advice from AR35 experts welcome 

Varch - what's involved in fitting the pump?

tunnie wrote on 28. Mar 2011 at 22:07:


They weren't overly smooth on the older firmware.

What state was the fluid in?

What mileage has it done?

First thing I would do is a fluid change and clean the filter out / replace and check for bits of thrust washer and other debris in the sump that might be signs of wear or damage.

Whining could be any number of things, IMHO, from a side-effect of normal operation to a bit of crud in a seal or valve, to a badly worn mechanical component. If it's serious I'd expect evidence in the bottom of the sump, though.

Kevin