Noticed my speedo was over-reading quite alot starting from cold this morning. I know it is supposed to over-read compared with more accurate GPS systems, but this was *very* noticeable, particularly in terms of what revs tend to make what sort of speed in a certain gear if you know what I mean. It appeared to be around 10mph more than GPS reading, but seemed to settle off to usual when warm.

It is also kind of wobbly going up and down a little. It has probably been a little like this in the past but maybe it's getting worse. Once I saw the speedo jump up quite high as I moved away (and I wasn't trying to drag race).

Just wandering what the likely problem is. I'm off to get some gear oil, so if I check it and find it's low I can top it up. But I haven't detected any gear oil leaks.

Thanks,

It won't be your gearbox oil, it's more than likely the speedo cable beginning to fail. Oh joyful job!

Seeing as you're going to whip the g/box end of the cable off anyway, see if the inner cable will pull out a little bit & squirt a bit of WD40 up into it.

that was just you, wheel spinning on the ice this morning!

Mine went on my Favorit - I ended up having a new speedo, but that might not be the case for you. I would start by spraying some WD40 as said above.

I have a spare instrument panel handy anyway so I'm lucky on that front if it turns out to be the speedo itself. I have fiddled with the thing on the spare one and can make it get to about 5mph I think by spinning it, lol. Ended my fun before it turned into clocking and adding a mile to it.

The tacho sometimes goes to max and then you hear the needle hit the bottom when turning off the ignition but I get the feeling that that's normal behaviour.

Looks like I'm going to have to get used to working on the car with ice on the ground. Brrr.

it could be gearbox oil working its way up the cable and gumming up the speedo head. ive known people with oil leaks in the car and this has been the problem

it could be gearbox oil working its way up the cable and gumming up the speedo head. ive known people with oil leaks in the car and this has been the problem

I think there's some sort of hole that's supposed to be unblocked to prevent the gearbox oil making it's way up the cable, where is this so I can check it? Thanks in advance

Did the WD40 down the speedo cable and it seems to have done the job.