Hello,can anyone advise me as to the max speed in each gear I can reach without over reving the engine. The vehicle is a Hymer motorhome based on a 1994 5 speed 2.5 TD Ducato. This old van is without a rev. counter, and whilst reading about increasing MPG, 2500 RPM was suggested to be the most economical engine speed.This is the first diesel engine I have driven and I have no idea what RPM I could be pushing the old girl up too. Although me and the van have come to an understanding regarding noise,vibration and time for a gear change it would be a comfort to know that I'm not asking to much of her.
Hope I hear from you before we disappear in a cloud of smoke and big ends.
Best regards to all and thanks for a great website.
Satchel.

Hi I have a 2.5td in my ducato if you have a handbook it should recommend the speeds for your gear change if not send me an email address to
[email protected] and I will try to send you a copy of the page I have
Cheers

I have the same engine in our 1991 Ducato 2.5td again with no tacho. Just choose your change points based on the noise and peak torque, you should be able to feel when it starts to go off the boil, and what road speed it will comfortably take in the next higher gear without bogging down.

If you are doing any long motorway trips, remember to change down to 4th gear now and again. It might save you a gearbox repair. Changing down throws oil up on to the 5th gear. A lack of lubrication is usually what causes 5th gear failure.