speedometer removal & gm400 oil & filter change

[ipburrell1962]

hi guys!
i am going to replace the speedo unit on my double six(the trip and milometers are jammed though the speedo itself continues to work fine!), what sort of job is this?,not to bad or a bit of a pig!?,also i am going to change the transmission oil and filter, as there is no drain plug the sump obviously has to come off anyway, anything to watch out for before undertaking this job? any advice welcome!, many thanks ian!!

[almcl]

Ian

I am sorry to say that I've forgotten which year your car is? Electronic speedo or cable?

Either way getting the instrument out of the dash board just involves pushing it in slightly and then a small twist (clockwise, if I remember correctly.) If it's mechanical undo the knurled attachment. Also remove the bulb holders.

You may find the speedo a bit stiff if it hasn't been out for a while, in which case carefully/gently prising the warning light panel out with a thin screwdriver may allow a bit more purchase.

Taking the pan off the autobox will only drain a couple of pints or so. Quite a lot of fluid is retained in the torque converter and other plumbing. Some prefer to disconnect the pipes at the cooler and pump it out by running the engine while feeding in fluid down the level stick. It's slightly scary the first time you try but it does a more thorough job of replacing fluid.

[ipburrell1962]

hi al
thanks for the advice,thankfully the speedo sounds an easy one!,also thanks for the tip on the gm400!!
cheers ian

[simon4253]

i had a 78 double six vanden plas which looked lovely and rusted like mad absolutely everywhere! be careful with one that has sat around a long time esp if not full of nice clean antifreeze and oil as could prove troublesome fairly soon. injection system and wiring not very reliable but mine had been neglected i think. i thought they drove better than series 3 but borgwarner gearbox a lot slower of the mark than gm400. I still want another though but probably coupe this time! hope speedo arrived ok. do let me know if it doesn,t behave and will dig out another,

[ipburrell1962]

hi there!
the speedo unit arrived wednesday afternoon,thanks again for your help,either phone or e-mail with the price and postage.
cheers ian