Could anyone tell me what oil to out in a 2wd Cosworth as I'm giving it a service and don't know what engine oil to put in I'd also like to find out what oil goes in the diff and gearbox Cheers Kyle

 

You will get many opinions, the actual reccomendation is 5/30 but I think this is to thin personally, I use 10/50 Sikolene fully syn you have a nice 50 weight when hot, this seems to be the most popular grade people use.

ATF for the gearbox, the oil for the diff should meet Ford SQM-2C9002-A (This is the Ford reccomendation when new) probably has changed now so long as it's for LSD.

Martin

 

As Monsieur Smartie says - you'll get many opinions based on 'fact' - the right oil for your engine isn't going to be the right oil for someone else's engine, because they're not quite the same.

You can either have a word with a tuner and ask their opinion, or, go to www.opieoils.co.uk (the Opie chap's also a member here) and ask their advice.

 

Ford specify 5W50 for the Escort Cos when it was new, I use 10w50 Silkolene ProS in mine. A lot depends on the mileage & how its been looked after.

It's a suck it & see as others have said, what is good for one car maybe rubbish for yours.

 

The reason ford said 5W30 was to do with MPG/emissions nothing more, it's pretty universally agreed this is no good, it thins way way too much when giving the engine grief, made even worse by the very small sump capacity, oils have come a long long way since 86 when the cos came out, I would not use anything thinner than a 50 weight if a few miles on the clock, and even a 60 weight with mega high miles, I'd be tempted to use a 40 weight on a new one whilst running in.
Speaking from experience of my 200,973 MILES on original pistons bore engine, as this is what I used/did.
tabetha

 

iv used 10w40 in my cossie for a few years now, free from work

 

Always better when it's free!!
With mine it used to drink 40 weights almost as quick as fuel, the only engine that had the classic 2wd piston slap even when fully warmed up!!
tabetha