MX-3.com

Ive put in 5-30w castrol magnatax synthetic oil to attempt to quieten down the ticking is this grade ok for the british climate, or is it better for colder temperatures?

says in the book 5w30 for COLD temperatures only...

that stuff is like water in our climate, you wanna be putting 10w30 (the book says) in the UK.

I've got semi-synthetic, 10W40 in mine and it runs fine.. no noise at all from the lifters, apart from occasionally they rattle for a while... (and very rarely one or two of them rattle for ages... scary stuff ) but its been really good so far on 10W40..

get that 5w30 out of there if i was you, too thin.. not enough protection unless your running under 5 degrees C kinda stuff... and that dont happen THAT often in UK summer LOL

Hmmm, I've got 10W40 GTX Magnatec Oil in my RS too.
Good stuff methinks - don't know what was in there before.
Seems to be OK. Engine runs quietly without rattling.

What is the real difference between 10w30 and 10w40?
(Don't say "10"!)

I can't find any 10w30 in the shops in Ireland, and can only get it (at considerable cost) from Mazda.

I used to use Castrol GTX Magantec 10w40 in my previous car, with good results. How does it work out in the V6?