If it's the same as the Citroen one then at the back on the left hand
side. Does this model have an electronic speedo? If so then there won't
be a worm drive but a sensor and a plug i cable.

405 TD Estate wrote in message
<1136379037.290573.299060@g49g2000cwa.googlegroups.com>...

It is driven off the right hand drive shaft.

There are at least three versions i know of.
early ones had a direct cable driven from the gearbox
next ones had an electronic sensor direct into the gearbox but with a
mechanical cable connected into the top of the sensor. Dash speedo is
mechanical but the electronic info connects to the ECU only
Later models only have the electronic sensor and electronic dash

Sensors come in at least 3 flavours.

1 has the full cable fitting into the top c/w hole to pass the cable in to
pick up the drive.
2 has the fitting to hold the outer of the cable but no hole to take the
mechanical cable. Initially looks like a substitute for type one but the
there is no ****ing place to fit the cable! Watch out for this is you are
getting s/h part from a scrapper.
3has a flat top and is obviously not designed for use with the cable at all
and was redesigned for late model, electronic dash only.

Mechanical cable is held in with a tapered rubber plug passing to the side
of the cable bush. Looks really naff but in practise is easy to remove
re-fit with pliers.

Electronic sensor (hall effect) is held into gearbox with a single 10mm A/F
hex bolt.

Intermittent speedo operation can be any of the following:

Cable problems, mechanical failure of the drive between input and output of
the electronic sensor or teeth stripped from the driven pinion in the
gearbox. (easy change 'bout a fiver for a new one from Pug)

If you are removing the sensor/cable/pinion from the gearbox, tip the car
over on a ramp with the right hand side as high as practical as this will
stop nasty smelly hypoid gear oil running down your arm.

Yup, just guess how I know all this..........

hth

bob