Speedo inaccurate.

Hi,

I am just wondering if some out there could possibly help.

I have been out today in my 1999 Conny 2.5 petrol/LPG for a toodle around, out of interest I stuck on my satnav and then, as the roads were quiet, using cruise control was able to potter along at 30, then 40 and then 50, according to my speedo. When checking with GPS speed all speeds were 5 mph less than speedo says. On the way home I was able to sit at 70 for a while, enough that the GPS was settled and it is still 5 mph out.

Whilst I know this is not vital, all I do is compensate, but as I like it all to work right is there anyway I might calibrate the speed.



Thanks in advance.

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