What engine oil for 3.9 V8??

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MikeV8SE

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Think it's time to change the engine oil on the old girl, so what would people on here recommend. She's approaching 90k on the clock, so getting towards higher mileage now - should that affect my choice?

I've always used the very best oil in the BMW - Castrol Edge Sport, 0W40 I think, but then that's a super smooth and relatviely high-revving engine (of similar mileage).

The V8 is lower revving and, dare I say, rather more agricultural - so I'm not feeling the need to blow £100 on oil if I can help it! Will standard Castrol stuff to the trick? Or even Halfords own brand? And what weight does it prefer? Don't have the handbook to hand!

Thanks! :)
 
Think it's time to change the engine oil on the old girl, so what would people on here recommend. She's approaching 90k on the clock, so getting towards higher mileage now - should that affect my choice?

I've always used the very best oil in the BMW - Castrol Edge Sport, 0W40 I think, but then that's a super smooth and relatviely high-revving engine (of similar mileage).

The V8 is lower revving and, dare I say, rather more agricultural - so I'm not feeling the need to blow £100 on oil if I can help it! Will standard Castrol stuff to the trick? Or even Halfords own brand? And what weight does it prefer? Don't have the handbook to hand!

Thanks! :)

15w40 -15w50 should be about right.
 
I use 20w50 race oil in mine. Bit of a bitch to get hold of (although you can get 20w50 normal from Halfords easy enough). Tend to get it from a rally tuner up north somewhere by mail order.
 
I found my 1990 3.9 didnt like 15w40 in the winter and it made it a bit tappety.

I went fot 14w40 castrol magnatec which it seems to love.

the 72 rrc 3.5 carb v8 only likes 15w50 it seems
 
Well the recommended goes from something the consistency of 3 in one to almost lard depending of climate so something in the middle should be ok. As said before 15W 40 - 50 is recommended for our climate. So you takes your pick.
 
look here..http://www.millersoils.net/1_Millers_frame_CLASSIC.htm

and on the rest of site..

ring them up and ask if in dought,ask for technical help..they are very good and unlike some (rang up most in the uk,via work etc)know their stuff..ie can i run abc oil in lt95 box etc..yes sir if is bronze and soft metal compatable..they know their products..


old design engine likes 10-40 to 20-50..depends on condition..
 
10w40 semi synthetic in both my late 3.9Efi RRC's.......and change it regularly (every 3000 miles or 6mths, whichever comes first)...Fortunately with an engine oil /filter change on a RRC I think is one of the easiest cars to work on.
Personally would sooner spend £30 on oil and change it twice as freqently then spending £60 on oil and leaving it in there.
 
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Thanks for the advice guys. The only 20W50 I could find was Halfords "Classic Car" type stuff, but most listed vehicles were non-Fi engines, and I know some 'older' style oils don't mix so well with FI systems.

Anyway, I went for some Mobil 2000 10W40 semi-synthetic - pretty middle of the road stuff so should be fine, and on offer at Halfrauds at £21 for 5L (had a foot pump and broken ratchet spanner to take back there anyway!). Also got 4L for 0W40 Castrol Edge Sport for the BMW, it runs really well on that and that too was on offer.

Will 5L be enough for an oil change? Or will I need 6L really? Not sure how much you can drain the sump or if you always end up with 500ml floating around in there...

Ta!
 
I seem to end up using 7 litres on the range rover and 8 on my bmw lol

the 72 rrc only take 6 litres tho which is good as its one can and a can of stp lol
 
Realistically any of the suggestions would be fine, just change it often (so it doesn't need to be expensive, or have amazing longevity).
I use Halfords 15/40 semi synth in a purple container, about £18 for 5 litres I think.
Mind you if yours is anything like mine there's as much coming out of it as you can put into it so its getting an oil change every 3 months anyway!
 
Good old straightforward mineral 15-40. Valvoline or similar.
Semi/fully synthetic doesn't do the old V8 any favours and is a total waste of money.

What do you mean "doesn't do it any favours?" Sounds ominous!!

I haven't changed the oil yet, prob wait til next weekend, so can take it back and swap it for that 20W50 stuff if people think that'll be better - this stuff: Halfords | Halfords Classic Oil 20w50 5L

Just 20W50 seems really thick to me, particularly for winter use!

Also, what oil filter should I use? I remember reading that some filters are really poor (Britpart perhaps, and another?) so can anyone recommend a decent one please - would rather not have to change the oil again because I've used a cheapo oil filter!!

Ta!
 
What do you mean "doesn't do it any favours?" Sounds ominous!!

I haven't changed the oil yet, prob wait til next weekend, so can take it back and swap it for that 20W50 stuff if people think that'll be better - this stuff: Halfords | Halfords Classic Oil 20w50 5L

Just 20W50 seems really thick to me, particularly for winter use!

Also, what oil filter should I use? I remember reading that some filters are really poor (Britpart perhaps, and another?) so can anyone recommend a decent one please - would rather not have to change the oil again because I've used a cheapo oil filter!!

Ta!

20W 50 is one of the recommended oils for that engine but only in hot climates. The grade recommended for our climate from the handbook is 15W 40 or 15W 50. So take your pick. Halfrauds oil prices are a bloody rip off by the way.
 
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