What Oil goes into Your Retro?

Good Topic! - as I'm always wondering whats best.
- Today I are be fitting these oils in these cars as thats what I've been 'advised' to do - please advise differently!

Capri Mk1 fitted with SD1 V8 gets the 10w/40
Granada Mk1 3.0V6 gets the 20w/50
BMW E30 325I & E30 318I get the 10w/40

Tend to use the Tesco/Homebase/B&Q route as I change oil @ every 2000 miles. Have been told MINERAL is king as synthetic isnt good for us 'Old Boys'.

if you regularly drive the vehicle for long trips them then the oil can be left in for ages,,,i change mine when it starts leaving moisture under the oil cap,,, which varies between 2000-6000miles on mine

cheap oil is just like any other "classic" oil,,,,,clean and with minimal additives,, oil only gets changed to refresh the degraded additives and remove the impurities that has built up in it (so pointless spending loads on expensive oil for a 50's designed pushrod motor,,, imo)

20/50 is really good for old motors with rubbish oil pumps but they have to be used for long journeys,,,,,cars used for little brief trips would make me fill with 15/40,,,,and changed more regularly

imo it's probably wise to go with the manufacturers recommendations ;D

My old Chevy uses that much oil I put the cheapest heaviest stuff in ! Once I get a decent engine I may go for the thinner stuff.

Some interesting points raised here. I thought synthetic (assuming it was the correct grade) could be better than modern mineral oils since it lacks detergents, but then I guess they are a modern oil, but then technology has moved on since then. Why is synthetic not suited to rebuilt motors? .

I have noticed that my '79 MGB on 15W40 starts miles better than the white one which requires some cranking before it splutters into life (or rather revs a fair bit, and then drops off). But the '73 car is on points, whereas the '79 is electric now, which would also aid starting I reckon.

Beetle I found ran better 15W40 Mineral than SAE 30. It used to overheat on SAE30, but was fine with 15W40, and I heard from VZi that Morris 30 is meant to be recycled oil anyway, so that may have had something to do with it.

Pug I tried with 5W40 (acceptable grade) and Total 10W40 Semi (what Pug recommend). It oddly ran better on 10W40 with better MPG too, or that was a great coincidence (It wouldn't get 200 miles to half tank before. Now it will hit 220 miles without a problem unless floored) with 400 miles to a tank becoming more of a common occurrence.

I think the phrase is 'any old muck'.

The Mini will genrally get what ever is cheapest, which is currently 'Comma' 10w40 Semi. Not that it stays in for long....rocker cover leak, crank end seal leak, diff seal leak, gear selector leak etc..etc.. I always leave my mark

I thought that leaking was a positive sign in a Mini . It means that it has oil in it. I understand for you any old muck applies, as Minis destroy oils via the 'box anyway right?

One day I'll own a Mini nonetheless .

using castrol gtx for high mileage cars in my polo g40 (done 150k), not sure what grade 15s40 i think, appears to be ok, only been using it for a month or so. before i was using castrol magnetec 10w40 but it kept vanishing somewhere, yet no signs of any major leak and no blue smoke?!
for my polo square i just use cheap stuff and its just an old banger really

Asda 20/50 in Sven at the moment, just over £4/gallon, and I was shopping there anyway when the oil light came on.

Before that was running on 10/40, but it was using some I suspect.

the 20/50 hasn't caused any problems, even in the recent cold spell.

Eep! I'd check your oil a bit more often! I've NEVER left any car so long that the oil light came on. Bad news as by then, the engine might already be eating itself and, as once happened to my wife (before I met and educated her!) the bulb might one day fail...