Volvo S40 1.9 115bhp diesel engine oil

[remydegreat]

changing oil in volvo s40 1.9 disel 140 miles on clock, i dont know its oil history,so is it going syntectic or semi ? also as car is old and 140 miles is it work putting syntethic in it ? opinions appreciated

[skyship007]

If you don't know the service history of an engine, the best thing to do is to assume it might be suffering from some degree of sludge or varnish.
Major brand full synthetic engine oils will clean up an old block faster than cheaper conventional oils, although it does vary between different brands. The best fairly cheap full synthetic in cleaning terms is Shell Helix Ultra 5w40 (Acea A3/B4), although Mobil 1 0w40 is also good.
The first few oil change intervals should be kept to half of the normal figure, so the detergents are still fully active.

If you get any lumps when the old oil is drained or other symptoms of more significant sludge, like a flickering low oil pressure warning at hot idle, the sump should be dropped for a manual clean up. It's also worth using an oil flush additive just before an oil & filter change, BUT only if the engine has no oil leaks (It can make oil leaks worse). Only use the oil flush additives that are designed for use at idle, not the drive around variety, as they are safer.

The term "Synthetic" has a different meaning in the UK and and USA to Germany. In those countries it includes HC Synthetic oils that are processed conventional oils, but the Germans only call an oil synthetic (A Synthoil) if it is a fully artificial oil made in a chemical factory. Only Liqui Moly, Amsoil and Redline make real synthetics, Castrol and Mobil only make HC (Hydro crack) synthetics. The real German standard synthetics are slightly better solvents and also resist high temp shearing in the turbo bearings better than any other type of base.

Once the block is clean, any major brand xw40 Acea A3/B4 full synthetic will do just fine. If you can't afford one then some of the major brand conventional oils like Castrol Magnetec 10w40 are OK, but keep the oil change shorter as they don't last as long.

I don't care too much which oil I use in a non turbo engine, as long as it has the correct viscosity and Acea specs, but if an engine has a turbo (Or a VVT) I only use top of the range full synthetics and never push the max oil change interval.

[remydegreat]

Thx a mill,great help

[allesnikj]

Skyship, Just wondering what you think about Total Quartz 9000

APPROVALS AND SPECIFICATIONS
API SN/CF; ACEA A3/B4
MB-Approval 229.5
BMW LongLife 01
Porsche
Most European OEMs

[skyship007]

Originally Posted by allesnikj

Skyship, Just wondering what you think about Total Quartz 9000

APPROVALS AND SPECIFICATIONS
API SN/CF; ACEA A3/B4
MB-Approval 229.5
BMW LongLife 01
Porsche
Most European OEMs

VW test a lot of different engine oils for their approved list, so any oil listed by them (Not one just listed as recommended by the oil company) should be OK. Here is a copy of their xw40 (A3/B4) list:
http://www.bobistheoilguy.com/forums...&Number=682986

It does mention Total Quartz so it's OK, although don't forget that most main block failures are caused by poor oil flow rather than actual bad oil, hence the importance of cleaning up an old block.

In general terms, although I use Liqui Moly Synthoil, I regard Shell as the best oil company in performance to cost terms and their Ultra is made from natural gas (It's a GTL base stock) and is a better solvent, which is one of the main reasons why they can make justifiable claims about better engine cleaning and even lower friction. The results I get in oil analysis terms indicate it's almost as good as the more expensive German Synthoils.

The big mistake is to use a DPF approved (Acea C or E groups) oil, as they have less Zinc based anti wear additives. I tested Castrol Turbo Diesel 5w40 (C3) for one interval and it double the wear metal figures, so this type of diesel does not like low Zinc oils.

[GP1]

Shell are also the only oil company to produce and line themselves their transport barrels to prevent any cross contamination..