Honda Jazz 2009 5dr Hatch 1.4 VTEC ES 107kMiles. Had recent gearbox oil change. In hot weather, now gets difficult to change gear after 10 miles or so.

[Paulus]

Hi, folks. My Mum's typically reliable Jazz has been 'serviced' for some time by a dodgy mechanic, as the Honda dealership service costs were beyond her reach, being a UK pensioner. Anyways, she recently had the gearbox oil changed and the new mechanic pointed out that the gearbox oil hadn't been changed for a VERY long time. Now, especially In hot weather, things get decidedly stiff when changing gear after about 10 miles or so. Any suggestions would be greatly appreciated. Thanks.