Speedometer given false readings

[Robbiem2307]

Hi, hoping someone can help. I have a 2005 2.8 Grand Voyager. Due to the car failing the MOT on rear parking brakes I have just had to have a new backing plate, new brake shoes, new hubs and new discs fitted. All works fine and has passed MOT but have now seen that the speedometer is around 15MPH out. When I start off it gets to around 15MPH before the speedo even starts moving. It worked fine before the work on the brakes. 

[bignev]

Hi there,

I think it's just a bit of a coincidence, sadly, as the gearbox has input and output speed sensors on the 41TE auto on ours, and to my knowledge that's how it gets the feed for the speedometer.

However, I stand to be corrected!!

The wheel sensors are for the abs system.

So it's very odd your speedo is now out of sync.  Perhaps the old trick of disconnecting the battery for half an hour might help the electronic brains to reset?

@gordy may have an idea on it? Hey pal!!?