Synthetic oil real synthetic oil like Mobil one of BP 5000 .Even if castrol modifies conventional oil its still not synthetic and magnatec is castrol the cheapest oil the garage can buy .Synthetic oil does NOT glug up the turbo and runs cooler .It also flows faster when cold and wear rates are way down .Sure its more expensive BUT so is a new turbo .Just look in side the oil cap of a car thats running on synthetic its like a sewing machine where as conventional oil goes thick and greasy .I use synthetic oil on my wifes sewing machine for that reason .
Any name brand synthetic is going to do you just fine. Some people get all caught up in Group III vs. Group IV vs. Group V base oil arguments, but in practice they all work extremely well as long as you stay within the specified oil change interval.
Check your owner's manual for weight recommendation. On my '96 Volvo
I've read that converting to synthetic on an older engine invites oil leaks. I don't know whether this is true or not, but there was a thread on volvospeed.com on which many complained of oil leaks on previously leak-free engines after switching to synthetics.
Mine is a non-turbo 850, an entirely different motor from the 940. The owners manual calls for 5W-30, 5W-40, 10W-30 or 15W-40 depending on ambient temperature range.
I took a deep breath and changed to synthetic on our '85 765T with 220K+ miles a couple years ago. When that worked, I did the same to my daughter's '93 Honda with about 200K miles. No leaks... but YMMV.
"Matthew Jenkins" skrev i melding news:6Tjnf.17417$ snipped-for-privacy@newsfe7-win.ntli.net...
I have the same car, and I've tried the Magnatec. No more.... in my engine. Some kind of charcoal-like substance nearly choked the oil return pipe from the turbo. And it was a smell of burned oil from the exhaust when the car was left for a few minutes with the engine running ....
Magnatec is not synthetic. It's only a modified mineral oil. The main problem in turbos is the temperature. Synthetic oil can stand a much higher temeperature. And the turbo becomes really hot under load. So.... Rule no. 1 for Turbocharged cars: Use synthetic oil.
I'm currently running my engine on Statoil LazerWay 5w40, and have used it for the last 3 years. No problems so far.... The oil return pipe is clean and the engine does not burn oil any more.
Well I think you'll find that it doesn't cause the leaks as such but rather in an older engine, the seals have hardened somewhat and oil residue has built up which helps plug the now harder oil seal.
Synthetic is a much better cleaner and as I have heard, will eventually dissolve the older oil residues which now leaves the hardened oil seal with a much harder time.
So it's not the synthetic oil which causes a leak, just old oil seals that are already past their use by date being helped out by gunky deposits.
reccomend Mobil 1 10W-30. Unfortunately so far as Ican tell, this is not available in the UK and it seems the fully syntheticoils sold by the main brand suppliers in the UK (Mobil, BP, Castrol) are all0W-n, where n can be 30, 40, other. The Castrol web site recommends 0W-30for this car. I am not that keen on putting a 0 rated oil in a car that is getting on of for 100,000 miles - especially as Volvo reccomend 10W-30 or 10W-40. My feeling is that using an oil that is too thin when cold might lead to insufficient oil pressure in places where it is needed. Is this right?
There are a number of other suppliers in the UK (e.g. Millers, Comma) that do fully synthetic 5W-30 or 5W-40, I might opt for one of these.
Does anyone know of a fully synthetic 10W-30 or 10W-40 oil available in the UK? Or, is there anyone in the UK who has got one of these cars to do a huge mileage without turbo problems, and if so what oil did they use?
You do not need 10W30 or 10W40 oils as the rating for fully synthetic is not the same as for mineral oils. I have Mobil 1 5W-30 Diesel in my Diesel Volvo
945 and the mileage is over 167,000.
All the best, Peter.
700/900/90 Register Keeper, Volvo Owners Club (UK).
My understanding is that oil pressure isn't the central issue, since the film strength is what prevents the parts from touching. Oil pressure is just the only indication we have that the oil is being pumped to where it is needed.
The big problem with low viscosity engine oils is the increased consumption.
B y the way in checking recommendations for 740 turbos I notice that synthetic is now recommended .Until recently dino oil was suggested .So the experts have finally caught on synthetic oil is better ,but also remember a good filter is needed with any oil as well....I got mobil 1 for $AU49.95 at super cheap here in Melbourne Australia its normally $AU 65.95 .
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