Is gearbox and diff fluid similar or they totally different properties?

I have a lot of oil for my T5 G.box and I have a welded rear diff, while I dont want any dameage to occur too the diff wheels would it be OK to use a litre of left over box oil in my diff or just spend the extra£7 on proper diff fluid?
Regards- tight *swear word* Mark

 

in a word NO dont use it!

 

as above.

 

As the diff is WELDED perfectly fine to use, lsd oil is totally different, gear oils are fine.
tabetha

 

id bung it in,its a welder!

 

err a mixture of opinions there? I know there is no diff plates to protect but is gear oil anywhere near the same as a diff oil? I have no idea

 

Mr C

how much does the rear diff hold....1-2 litres.

£10-£20 max for proper diff oil.....its up to you.

 

At the end of the day its an open diff that you welded up - stick any old gearbox oil in and it will be fine

 

Gearbox oil and diff oil, (for non LSD's) are just made to withstand shearing and messhing forces.
If in doubt phone up oilman 01209 215164.
tabetha

 

I decided on the proper stuff, it holds just 1.2 litre max Dave , after buying diff oil and comparing the two- box and diff oil are nowhere near the same, I would say box oil is like water compared to the diff stuff so yes I spent the cash- all £6.99 of it

 

I get what your saying Graceland, welded diff is cheap to replace after all, just hate doing stuff twice if not needed