Changing to Synthetic Engine Oil

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ScottFromNZ
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Changing to Synthetic Engine Oil

Post by ScottFromNZ »

I have changed several petrol cars to synthetic oil over the years with no problems. The TZD is my first diesel though and I am wanting to change it to Delvac 1 at next oil change as I bought 20 litres off a friend who had sold his diesel car and did not need the unused oil.
Has anyone changed to synth on one of these engines and had seal leakage problems? I would hate to change and have the cam seal start leaking oil over my new timing belt! For this reason I am reluctant to flush the engine. I have seen older engines flushed and then leak.
When I change to synth would you recommend a first oil change in a short time due to higher detergency of synthetic oil?
The new mineral oil I put in went black after about 200 km of driving - but this may be normal for a diesel engine.
In my petrol cars the oil stays almost like new in colour for up to 5000 km's.
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Kowalski
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Post by Kowalski »

I changed a Xantia TD over to synthetic and it didn't leak oil or use oil, it had only done around 57k at the time. There didn't seem to be any advantage to the synthetic oil over semi-synthetic in that engine, so on cost grounds I went back to semi-synth.
Diesels do dirty their oil very quickly, the reason being that quite a lot of oil is left in your engine when you do an oil change (an oily residue covering all of the inside) and this oil contains soot. As soon as you start the engine this soot ends up in your lovely new clean oil, a little bit of soot goes a long way and hey presto black oil...
ScottFromNZ
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Post by ScottFromNZ »

After all I have read about synthetic oils I will be happy changing every 10,000 km (6000 miles) on full synthetic instead of 5 - 6000 km's on mineral oil. This means overall cost is the same as synth is nearly twice the price of premium mineral oil.
ohms69
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Post by ohms69 »

What synthetic diesel oil's do people use in the UK? I'm having difficulty finding a Fully synth diesel designated oil.
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rabenson
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Post by rabenson »

I'm not convinced of the benefits of fully synthetic over semi-syn. I think I'd rather change my oil more frequently and get rid of the sulphates and other crap that tend to accumulate. I know that Fully synthetic oils maintain their lubricating properties much better over the long term, but with frequent oil changes is that really an advantage? This is a genuine query and I'm prepared to be shot down in flames by those more knowledgable than me......
rg
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Post by rg »

ohms69,
I raised this a few months ago. I think that the conclusion was that anything with a "C" designation (such as "API *** C3")is fine. "C" for compression, I think...
I think that there is something in the archive...
HTH
rg
ohms69
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Post by ohms69 »

I will only run mine on fully synth now it's had the power upgrade. That turbo whistles it's head off...I want to ensure it gets the best protection possible!
Halfords 5w-40 fully synth it is then...Half price at the moment £14.99 for 5 litres![8D]
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Post by rg »

ohms69,
Both my XM and the VX Monterey (3.1 4x4)use the Halfords stuff which, I understand, is made by Shell for Comma, and then rebadged by Halfords. At that price, it's a bargain.
When towing 2.5 tonnes, the Monterey's turbo whistles like a "125" Diesel Locomotive at full power, so I'm glad of the protection
rg
NiSk
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Post by NiSk »

It maybe intersting for some of you to read the comments that of one of Sweden's truck manufacturers (one of my customers) has to say about synthetic oils:
Synthetic oil</rtit>
<p>Synthetic oil is being used increasingly for the lubrication of vehicles. The raw material for these oils is the same as for mineral based oil, crude oil, but the manufacturing process is quite different. As a rule, synthetic oil has better temperature stability and cold properties but its friction properties sometimes result in synchronisation faults. Synthetic oil can also have a negative effect on sealing materials. It is therefore important to use approved synthetic oils. </p>
<p>A synthetic oil is not necessarily better than a mineral oil. This is however a common misunderstanding and it is therefore often assumed that oil change intervals can be extended. The service intervals recommended by V*l*o apply irrespective of whether the oil is mineral or synthetic.
But thats when using it in big bad diesel truck engines (my comment).
//NiSk
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Post by BatteryMan »

My pennyworth - I ran an Escort TDi for 50K miles, switching to Millers fully synth when I bought it. I contacted Millers for recommended oil change period - could I extend from the recommended 6k ?. They operate a FOC service where they will take a sample of your Millers oil, examine it, and provide a detailed printout about oil and engine condition, with recommendations. I sent a sample after 9k miles, the results came back within a week, with recommendation of an annual oil change - or about 12k. The car did not consume any oil between services, and I sold it at 122k.
I changed to Millers as a colleague used this in both of his TUDs - 309 and 205. I shall change when service is next due on my Xantia TD.
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Post by Robin »

Thought you may be interested in this. It is piece from the techie bit of an oil company we use for oils in high speed marine diesels.
I use ordinary mineral oils in my diesel Xantia and change it every 6K. Prefer to have the rubbish out and it only takes 20 minutes.
SYNTHETIC ESTER-DIESTER ENGINE OILS
The most extensive line of fully formulated synthetic Ester-Diester engine oils containing an additive package that meets or exceeds all requirements for gasoline and diesel engines where an API SJ/CG-4 quality is recommended. These outstanding engine oils outperform premium petroleum motor oils, all seasons of the year. For gasoline, diesel and turbo-charged engines in cars, trucks, vans, buses, boats, ships, and heavy equipment.
Contains no petroleum oil base stocks. Formulated with 100% genuine Ester-Diester synthetic oils (commonly referred to as jet engine lubricants), special detergent dispersants, corrosion inhibitors, anti-wear additives and VI IMPROVERS. Ester-Diester oils retain their viscosity at extremely high temperatures (470 F) for extra protection in hot summers, yet pour freely at sub-zero temperatures (-60 F) for easy starting in cold winters. They resist oxidation and viscosity breakdown much better than petroleum based oils. Ester-Diester lubricants have a powerful cleaning action capable of dissolving and suspending harmful sludge, varnish and carbon deposits which keep engines and lubrication ports cleaner and in top performing shape. They are more highly biodegradable than petroleum based lubricating oils. KEM-O-PRO Synthetic Engine Oils help to:
Reduce friction, engine noise and engine wear.
Lower volatility and oil consumption.
Extend oil and filter change intervals.
Reduce fuel consumption and operating costs.
For automotive, transportation, marine, fishing, construction, mining, agriculture and manufacturing.
ScottFromNZ
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Post by ScottFromNZ »

There is a lot of info on the internet about an oil called AMSOIL which is a synthetic oil. In some trucks with this oil they have left the same oil in for hundreds of thousands of miles with bypass filtration and regular oil analysis. They have stripped engines to find very little wear after these extended drain intervals.
Maybe I am being paranoid about the leakage issue with synthetics - Mobil Delvac 1 is even said to be mixable with mineral oils so they must be quite chemically compatible.
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Post by arry_b »

I changed to fully synthetic at around 80K.
1. Engine runs smoother than it did on mineral, but not noticeably so compared to semi synthetic.
2. No leaks produced.
3. The engine is still pumping contaminates into the oil at the same rate so its still appropriate to change at the specified intervals. The reason for more frequent oil changes on a diesel isn't so much that the oil is worn out - more like it's full of sh** that is better off out of your engine!
Even if it's double the cost of mineral, what's that over the life of the car? Not a lot, even before you factor in the less tangible benefits like longer engine life and better fuel economy.
If you're in the UK and don't want to get your hands dirty - Kwikfit will do a fixed price oil and filter change using mobil-1 fully synth for £29 all in, which is cheaper than you can buy the oil for yourself. Of course, the filter will be non-genuine (take your own with you), and they'll tell you that you need four new tyres, an exhaust centre box and your back shocks are leaking (even if you've got a BX!), but their oil changes can be good value.
My mate with an Estima same as mine (see my sig) paid the £29 standard charge for his last change - that included a £15 oil filter (Jap import MPV) and 7 litres of Mobil 1. It would have cost him about £80 to DIY!
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