Using Dexron III instead of MErcon V - Surrey_Scientist

Further to my last post about geting hold of Mercon V auto fluid.....

It seem Mercon V is a synthetic fluid with a higher spec than Dexron III.

Only fluids I Can find that meet this new spec are AMSOIL Universal ATF, which comes from the US, only supplier Ican see is and they want £40 for 5litres

Mobil 1 synthetic ATF also meets this new spec, but I can't see a place to buy in the UK (online at least).

Can anyone tell me is it OK to use Dexron III instead, and change regualrly, eg every 6months or 1year (I do approx 8,000 miles a year) as this is an easy job to do.

I intend to use my Mazda6 for towing a 4berth caravan, so wish to installa fluid cooler, and replace the very fluid regularly.

Need to do a fluid change in the meantime anyway, as stuff in it is discoloured....

Apparnetly Mazda6 autobox is same as that used in Ford Focus, if that helps (anyone know what fluid gets used in this ?)
Using Dexron III instead of MErcon V - Aprilia
No, you shouldn't substitute Dex III for Mercon V unless you add Lubegard MV to bring it up to spec.

If you don't mind ordering from the US then Philip Legate at sells 'AutoGlide' ATF to Mercon V spec. Its about £20 a gallon and his shipping to UK is not too dear (or at least it wasn't when I last ordered some about 6 months ago) - should work out cheaper than the Amsoil.
Using Dexron III instead of MErcon V - mgbv8
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Using Dexron III instead of MErcon V - Aprilia
Simon or Guy at


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