Mixing OAT coolant with others

When I purchased my 1999 TD5 Discovery about 6 months ago it came with a main dealer service and the coolant had been changed and refilled with OAT coolant. I needed to top up because a slight water pump leak had developed and because of the ice and snow I just used Q8 (?) coolant from the local garage that said "suitable for all engines including aluminium". In these days of product liability I am sure (hopeful?) that if they say its suitable for all engines it must be. I then topped up again with another brand that said the same thing.

Now according to the Drivers Handbook this is a *VERY BAD THING* and I should have used water in the absence of OAT and topped up with concentrate when the opportunity arose. Is my expensive LR coolant now trash or has coolant technology moved on in the 11 years since my car was manufactured and the manual written.

Thanks

Depends how much of the Q8 coolant you put in.

More than a cupful and I'd suggest changing it all.

The main benefit of the OAT stuff is the anti-corrosion properties, very necessary on an aluminium engine. There is no known mixture allowed with OAT, so if you've done that twice then it is necessary to change it all.

50/50 mixture BTW.

Peter

look in the FAQ section - ifit turns to jelly - dont say yu aint been warned

What colour is the Q8 stuff most companies do a universal ethylene glycol antifreez now so if it's pink or red you should be ok, if it's the green, green/yellow or blue that when mixed with OAT antifreeze caurses problems.

http://www.filtercouncil.org/techdata/tsbs/05-2.pdf

Strangely the early TD5's don't use OAT even though they have an aluminium head. It's only the later ones that use it.

my 1999 discovery says only use oat coolant in the hand book and on the head tank but tdi engines run ok on the blue or green stuff dont see why a td5 should have a problem but as said dont mix them and i still use the oat

ratty said:

Strangely the early TD5's don't use OAT even though they have an aluminium head. It's only the later ones that use it.

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my handbook dont say that

http://www.landyzone.co.uk/lz/f38/mixing-antifreeze-62372.html seek and yu shall find

I have been runing on OAT for the last 6 years just renewed it again last year, the only every 5 years replacement sold it for me.
Before that it was the Rover green/yellow stuff that required replacing every two years.