Quick question about engine oil

[glacierboy]

Just a quick one, really....

I have always changed my oil and filters on my 300TDi, and have used Castrol GTD Magnatec (and paying for it!). However, I have noted that this is never mentioned in articles in the big magazines, who simply recommend any oil of 10W40 viscosity.

Is there any evidence to show that one brand of oil is any better than another, because I found equivalent oils by Millers to be half the cost of Castrol or Duckhams? Any advice would be gratefully received, because it could save me a fortune!

[Lightbulb]

Just a quick one, really....

SNIP
Is there any evidence to show that one brand of oil is any better than another, because I found equivalent oils by Millers to be half the cost of Castrol or Duckhams? Any advice would be gratefully received, because it could save me a fortune!

I believe that top quality oils are better than cheapos, but not pro rata - you are still paying a premium for the name as wells as the better quality.

I tailor the oil to the engine output - if I was driving a turbo charged, high output per litre, highly strung engine that revs to 12,000 rpm I'd use the best quality, synthetic oil I could get. Mind you, a friend had a turbo-diesel Primera, and always ran t on synthetic in order to try and get 200 thou miles out of it. The engine management electronics packed up at 120k miles and it was all for nothing ! Sods law.

On a landy I use a good down to earth oil from a mid range manufacturer that's not going to go bust, knows what they're doing and has got experience.

I also think that if you're doing short runs, stick religiously to the recommended oil change interval, or do it sooner.

Lightbulb.

[shadyadie]

I used magnatec in my 300 tdi for the same reason but I have a question


If the magnatec sticks to all your engine parts how do you guage the oil level ??:rolleyes:

don't think I will use it next time as with the recommended oil changes its going to be very expensive at nearly £40 a go..

[kevinrbeech]

A local retailer put it to me that if I was going to change the oil every 6k or less, did I really think it neccessary to use a long life oil.
I suppose he has a point.

[Roger Whittle]

I'd like to get in on this oil question. This is my first diesel for thirty years and certainly my first in a nice car. Like one of your contributors, I use my Disco for work and very often just grind around in London as well as the odd dash to say, Guildford or Norwich. Does that sound like a reccommendation to change the oil on a regular basis and for reasonably good stuff too? Any suggestions as to mileage and oil type? I go off road now and then (mostly scout camp sites), but nothing arduous. It's mostly working around town and towing trailers fairly regularly.

[glacierboy]

Thanks for the comments: I'm glad that others are posing the same question: if the oil is changed every 6,000 miles, does it need to be a high spec oil? I keep reading comments by folk who say that quietness, economy or performace improved with their own specific favourite oils, but is this really the case?

For myself, i think I will try the Millers oils this time round, and post a note if I find out anything interesting....

[roverX]

I am running a synthetic blend, 20w-50, in my 96 D1, 140,000 miles. I change it every 5000 miles. This is what was recommended to me by a retired LR underwriter. I have a petrol engine. I run pretty heavy offroad and it is also my daily driver. My $0.02 cents.:)

[turbine_2]

Most of this comes from what I've been told about engine oil.
The problem with oil is that as it's used it starts to become slightly acidic. Turbo diesels are very hard on the oil (hence the low milage service interval) but putting in long life oil isn't going to make much of a difference. Longer life oils tend to be longer life because they're designed not to break down due to the churn that they go through (one of the reasons that most bikes have such short service intervals is because the oil not only does the engine but also the gearbox).
20W-50 is what I've always been told to use for the 300 TDi engine and I generally stick to a branded oil. Putting some big name oil such as Magnetec isn't going to harm anything (other than your wallet) but with the service intervals being used (6000 miles) I personally wouldn't spend the extra. On the other hand, oil is the main thing that will extend the life of an engine so it's worth looking after what you have in there.
One of the reasons that's been put forward to me as to why diesel engines last so long is that diesel is a pretty good top end lubricator.

[6Limetree]

For the TD5, the owner's handbook recommends Castrol 5W/30 meeting specification ACEA A1+B1.

5W/30 will protect from -30C to +35C

10W/30 will protect from -10C to +30C

10W/40 will protect from -10C to +50C

Why bother trying to save 10 or even 20 quid on oil

[Mike_Hammond]

As has been said before if your changing the oil every 5 to 6K then there is no point using expensive synthetic's as a normal oil will cope just as well it's just a waste of cash, TBH agood semi-synth will easily exceed this mileage.
Infact most modern engines will run quite happily upto 15K-20K on a fully synth oil (dependant on use obviously) so I would expect something like Magnatec to cope up to at least 10 - 12K.

What you have to remember is most manufacturers will air on the side of caution, we run Renault TDI vans and they have 20K service intervals !!! :eek: two of these vans are now topping 180 thou and still going strong, but then they do mainly motorway work.

[roverX]

I am under the opinion that it is not wise to go with long service intervals with rover engines due to the fact that they "collect" so much junk from the petrol and the emissions. Even if you run a synthetic designed to last longer, your engine is still collecting junk in the oil pan. If you go with longer sevice intervals, you will have more junk in the oil pan, therefore, leading to the possibility of "bad" stuff happening to your engine.

I use a synthetic blend (Castrol) which costs me about $2.79 per quart in US dollars. I like it b/c it gives me the protection of the lubrication of synthetic. I also change it regularly too (see previous post).

[dirkmc3]

all oils have the greatest amount viscosity breakdown in the first 500 miles...Some more than others. The snynth's hold up a little better in this initial period and a little better in the long run....but not much. Sunstituting a quart of full synth to your next oil change and you will accomplish the same task. Also as mentioned, the blends perform on par with full synth.

I got this from a white paper published from, I believe ,a Univ of Southern California engineer. They did viscosity and longevity testing on 10-12 different oils..... I'll try and find the link...it was pretty interesting stuff and changed the way I look at oils immensely.

For the record....castrol GTX with a quart of syntec.3-4K miles between changes


OFF topic....but ......As for diesel oils...I use them now in my Motorcycle...high metal content and increased shear resistence....works well in a cycle gearbox....been using Shell Rotella or Mobile Delvac.

[glacierboy]

Many thanks for all your words of wisdom.... the question is a bit academic, because I have started suffering from a recurrent stalling of the engine, so mundane issues such as servicing have been put aside whilst I try and sort out this new fault.... Think it is something to do with a faulty Earth connection. Somewhere. Maybe.

[roverX]

When was the last time you cleaned the injectors?:rolleyes:

[Henk Coetzee]

The common wisdom in South Africa on oil in a Tdi seems to be to change every 5000km (yes, about 300miles). Bear in mind that this is based on high temperatures, lots of dust and a highish sulphur content in the diesel, which leads to acid formation, although this is due to improve next year. As for oil, the accepted wisdom is to use Caltex Delo 400 15W40 in turbo diesel 4x4s.

The difference in price between this and a cheaper oil amounts to less than a quarter of a tank of diesel, which IMHO is a small price to pay for peace of mind. It may well be OK to run on a cheaper oil, but look at the price of the oil in relation to the other costs of running the vehicle.

Another important thing to look at in an oil change interval is the time that the oil is in service. From Pretoria, 5000km corresponds to driving to Cape Town and back a bit less than twice. This could be achieved in around 50 hours (although why anyone would want to do that beats me). Drive the same distance in the oil-killing stop start town driving and you'll have the engine running for about 5-times as long. Continuous heavy offrorading in low-range could take even longer. Now go figure why aircraft engines are serviced based on hours of service, rather than mileage.

Henk

[stowville]

I have always used good quality Fleet 15/40 oil in all my diesel vehicles for the last 15 years. My old peugeot is now with a new owner but has now done 205k miles with no probs at all.
I pay about £30 for 25 litres of it and if its good enough for lorries its good enough for cars and landrovers.
The important thing is to change it on time and use a proper oil filter

[glacierboy]

Lots of very interesting information there: from what you all have to say, almost any oil of the right grade (15/40 or therabouts) is fine, as long as you do the changes at the right interval. It doesn't seem that any particular oil is any better, but that as long as you change the oil and filter every 6000 miles (or less), everything should be fine.

Thanks for all your comments (so far) on what I thought may be a dull issue: they have all been very helpful.

PS: Think I sorted out the engine cut-out fault: yet another failed Earth conection. My car is beginning to have a spiders web of little wires connecting components to the chassis now!