MPH???

[mark aitken]

Hi,
I've just bought an S plate 190 LWB. On my sat nav it says I'm doing 60 mph but the speedo says 80! The engine seems to be revving its knackers off at this speed. Does anyone have any clues? Is it possible its got the wrong gearbox on it???
Thanks.

[rover]

Its possible it has a petrol gearbox in it but that wouldnt make that much difference, its more likely that it has a very low ratio diff in the back axle.

I assume it is a five speed box? it certainly should be but you never know what previous owners have done!

Rover.

[mark aitken]

Yeah its a 5 speed box, roughly what should it do to the gallon with a low ratio diff? its doing anything between 22 - 30 depending on load.
Mark

[Luke]

Yeah its a 5 speed box, roughly what should it do to the gallon with a low ratio diff? its doing anything between 22 - 30 depending on load.
Mark

well if your speedo is that far out your mpg will be too so in effect 22-30 will actually be less what are you carrying when you get 22mpg?

like rover says its prolly had an axle swap - but also are you running standard sized tyres

[mark aitken]

Standard size tyres, carrying approx 1000kg when getting 22 mpg. How can you tell the ratio on a diff? Will a standard diff be easy to get? And how much approx?
Thanks Mark

[100ps_drw_hicube]

mate there is usually a tag on the rear diff cover plate it should say on there

[rover]

And the higher ratio ones are not easy to come by, thats probably why its got a low ratio one in it..

Rover.

[100ps_drw_hicube]

by chance i was looking for a 4.63 for mine which i got i happened to look thru the local friday ad and found another so i grabbed it quick