Oil is browny red at 144000 miles. Would like to do oil and filter change but have been advised by local specialist to leave well alone and change the vss to cure speed problem. They say that a change of oil will cause further problems for the box because of the residue built up inside.
Are they right or just looking for business???? Any advice would be appreciated greatly

 

Do you mean the auto fluid/filter?

What engine? Cosworth, 2.3 etc?

What fault/symptoms are you trying to fix?

 

There is no residue inside that is holding the box together, the residue is a build up of varnish usually from old oil, this can affect the general performance, particularly with shifts.
Detxron oil goes brown due to age and contamination, it will do no harm to change it, it also will not stop a fault the box may have.
The boxes do have a few probs as they get older, most notably diaphragms going hard and speed issues affecting one gear only.
tabetha

 

Sorry Combatsapph, should have mentioned it's a 2.0 scorpio ultima and yes the autobox fluid and filter.. Speedo works fine on short journeys but goes erratic on motorway run showing 30 while doing 70. Vss?????

 

Hi Tabetha, do you recommend changing the filter as well. Will check electrical connections for wear.

 

If it has a easy accessible filter then may as well swap it out.
tabetha

 

undo the bolts underneath
change the fluid and filter
job done

just don't expect it not to be messy