I'm thinking I ought to change the gearbox oil and filter as I know the car has done very little miles over the past 2-3 years. Just been stored mainly. Can't be good for the oil.
My question is will any Dexron 3 rated or above oils be ok?
I used to have auto volvos with a gearbox made of cheese just like the td6 and as a result bulk bought oil.
I've got around 10 litres of carlube ATF JWS 3309 left that it seems silly not to use if it's fit for the job.
Any thoughts?

There has been much discussion on this subject....

I'd suggest searching for posts by Bemble...or doing a goooooooogle search for RRPhil and see what he says.

The original oil for the GM5L40E was a Texaco Texmatic oil.....but I am sure that Dex III was listed as an alternative by RRPhil.....but search for his posts first before you take my word for it!

I'll do that now thanks Saint

So I decided to buy the advised Texmatic oil for the gearbox. 20litres delivered for £82
Obviously I won't need 20litres.
Anyone doing a gearbox oil change wants to buy any off me? I'll inly charge the same as what I've paid plus postage. Just don't see the point in having loads sat in the garage for years. I'll keep enough to do another sump dump so guess I'll have 10-12 litres to sell.