406oc.co.uk

I currently use 10w 40 semi-synthetic on my SE 110 HDI 04 and change the oil annually which is due in about 3 months time.
In the meantime can I top up using some fully synthetic 5W 40 left-over which I am trying to use up? My gut feeling is that I
should not risk it but others may have a different view. (Makes you wonder what happens on the garage forecourt where
top ups take place on a daily basis using who knows what grade of oil!)

The oil whats already in, will of thinned down by now perhaps.
so adding 5w-40 oil over 10w40 shouidnt do any harm iwouidnt think,

but icouid be wrong tho,

isnt the hdi meant to use fully synthetic anyway ? (i always thought it did)

I always used semi-synth 10w40.

Me too.

ok i thought wrong then

Ok to mix.

Btw. I lube my 110hdi on 5w30 fully synth. This oil is the spec for FAP. Mechanically the engines are the same.

Saves fuel by reduced oil friction.

Probably excessessively, change oil every 6k. But as oil and filter only £16,feel it is worth it for cleanliness on 140,000 engine.

Peter

I agree with gary, HDis should use fully sinth, it is always better. Possibly grade 3 or higher.
Also mixing full synth and semi synth is said not to be a good idea, as much as mixing two different oil densities isn't: it's like (this is extreme example) mixing oil and water, two different qualities will not mix properly and you'll have a kind of oil here and another there: not good for vibrations and such.
Last month I got myself 10 liters of Castrol EDGE FST 5w40 for 7£/liter (ebay), which is extremely good. I heard on the coupé forum that it was offered at the same price at Costco or somewhere like that.

6speedmanual wrote:Ok to mix.

Btw. I lube my 110hdi on 5w30 fully synth. This oil is the spec for FAP. Mechanically the engines are the same.

Saves fuel by reduced oil friction.

Probably excessessively, change oil every 6k. But as oil and filter only £16,feel it is worth it for cleanliness on 140,000 engine.

Peter

Sorry 6, this is not right. The fapped 2.2, and every fapped 406 HDi, should use 5w40 (I'm readng it from the manual). Also, what tells if the oil is good for the FAP is the ACEA specification. It should be ACEA C3 (low ash).
Also, how the hell can you get 4.5 liters of oil and filter for 16$? I'd suggest you to get a better oil and maybe change it more often... for 3£ a liter you are probably putting in recycled chips oil
At least if you don't have a secret and extremely cheap place where to buy oil!

Odin

I'll be more specific.
I use 5w30 AECA A5/B5 fully synthetic.
I was refering to the viscosity being suitable for the mechanical aspect rather than the low ash required for the fap.
I read somewhere that when Peugeot introduced fap the possible oils were 5w40 or 5w30.
Also in my 406 handbook it states that 30 grade is ok for ambient temperature up to 40'C - I can only dream that our summers could be so warm!
I buy the oil in 20l drums from Unipart. In Dec was £54. Just bought another today for £76. Big price increase but still much better than high street retaillers.
I can run all 4 family cars on this simplifying purchace and storage.
As for the chip oil, well that is kept for a different use altogether! ;-)

Peter

6speedmanual wrote:Odin

I'll be more specific.
I use 5w30 AECA A5/B5 fully synthetic.
I was refering to the viscosity being suitable for the mechanical aspect rather than the low ash required for the fap.
I read somewhere that when Peugeot introduced fap the possible oils were 5w40 or 5w30.
Also in my 406 handbook it states that 30 grade is ok for ambient temperature up to 40'C - I can only dream that our summers could be so warm!
I buy the oil in 20l drums from Unipart. In Dec was £54. Just bought another today for £76. Big price increase but still much better than high street retaillers.
I can run all 4 family cars on this simplifying purchace and storage.
As for the chip oil, well that is kept for a different use altogether! ;-)

Peter

In my handbook it is stated clearly to use only 5W40 ACEA C3 oil with the fap. I highly doubt an unknown brand unknown make unknown grade (in the sense of the oil bases with which it's made) is anywhere near as good as a premium and tested one, like Mobil1, Royal Purple, Edge, Magnatec, Helix Ultra and such, I'm sorry.
I'm sure that's a great deal on oil, it's really really cheap! However I'd stay miles away from using that on my own car. That said, cars in UK are so cheap you can definitely afford to mantain them cheaply. You can get a new 406 for less than I paid in taxes when I got mine! (400£)

There is a huge issue with oil prices in UK and probably globally.
The AECA specifications are there for a reason - to ensure the engineering standard required.
Sure, some companies will claim this and that for their oil and in some areas they may claim some advantage. Whether these are tangible in terms of engine wear, cleanlines and fuel economy is questionable.
Unipart is a very reputable parts aftermarket and OEM manufacturing parts supplier. They may source the product from various oil companies, maybe even some that you list. The point is they buy it and sell it on specification. I have little doubt that the oil I'm buying is up to its quoted spec and up to the job in my car.
The retail oil market is dominated by heavily marketed brands. All those mentioned are fairly well known from advertising or product placement.
Retailing Mobil 1 at £50 for 4l gives plenty of margin for fancy advertising and also 'discounting' promotions which make it seem not quite so expensive.
Buying in small volumes is also a price driver. The best price I get in 5l cans is about £4:50/l. Sure many people would find 20l too much to have to buy in in go.

Servicing garages are constantly exploiting this price perception. Buying bulk oil, often branded Mobil etc for a couple of quid per litre and retailing it at similar or higher prices than Halfords. Ouch, wallet pain.

I've been around automotive engineering too long to be taken in by all the hype and the retail margins. Prefer to know the spec and what it does.

Peter

6speedmanual wrote:There is a huge issue with oil prices in UK and probably globally.
The AECA specifications are there for a reason - to ensure the engineering standard required.
Sure, some companies will claim this and that for their oil and in some areas they may claim some advantage. Whether these are tangible in terms of engine wear, cleanlines and fuel economy is questionable.
Unipart is a very reputable parts aftermarket and OEM manufacturing parts supplier. They may source the product from various oil companies, maybe even some that you list. The point is they buy it and sell it on specification. I have little doubt that the oil I'm buying is up to its quoted spec and up to the job in my car.
The retail oil market is dominated by heavily marketed brands. All those mentioned are fairly well known from advertising or product placement.
Retailing Mobil 1 at £50 for 4l gives plenty of margin for fancy advertising and also 'discounting' promotions which make it seem not quite so expensive.
Buying in small volumes is also a price driver. The best price I get in 5l cans is about £4:50/l. Sure many people would find 20l too much to have to buy in in go.

Servicing garages are constantly exploiting this price perception. Buying bulk oil, often branded Mobil etc for a couple of quid per litre and retailing it at similar or higher prices than Halfords. Ouch, wallet pain.

I've been around automotive engineering too long to be taken in by all the hype and the retail margins. Prefer to know the spec and what it does.

Peter

I also buy in bulk from a ebay seller I trust, but I choose the oil based on independent tests. There's a couple of forums I follow on which often oil is a topic, and I've seen enough horror stories from cheap oil. However, if you find it's OK for your car, then it is. Here, at least, not all mechanics buy oil at such low prices, for example I recently sold 12 Liters of Castrol SLX professional powerflow 5w30 (VW oil, 13+€/l on the market) I got for almost nothing to a mechanic who paid me 8€/l. Either he is stupid or he doesn't get to buy good quality oil as cheap as you do!

I did nearly 40k in my first year of driving in my XUD. Used to use Asda/Tesco brand 10w40 Semi or 15w40 mineral based oil. Used to change it every 3k.

Eventually the oilways were so clean the oil used to turn to a nice dark goldy colour instead of black.

I used to give my 406 death. Running 22psi's of boost, long periods of high speed/full throttle. Coolant temp used to go through the roof. But the engine never put a foot wrong!

It was then detuned and done another 10k/6months of start/stop driving through a very cold winter. Starting with no glowplugs at -10°c etc.

I really think the only reason that engine lasted was due to the fact it always had clean oil!
Heck I even used to run it on veg oil that was only filtered through Jcloths!

But when we got rid the engine was still going like a metranome! I really respect that engine!

I personally would rather clean cheap oil than expensive oil changed at long intervals.

Both my Focus and HDi get treated much much nicer and I do get a good mid range oil (Valvoline/Castrol etc) and generally spend about £30 on 5 litres and I change the oil every 6k/6months.
But although I have considered dropping to 5w40 Fully synth in my HDi and doing the normal 12k intervals, I feel much happier with 10w40 and 6k intervals.

Bailes1992 wrote:I did nearly 40k in my first year of driving in my XUD. Used to use Asda/Tesco brand 10w40 Semi or 15w40 mineral based oil. Used to change it every 3k.

Eventually the oilways were so clean the oil used to turn to a nice dark goldy colour instead of black.

I used to give my 406 death. Running 22psi's of boost, long periods of high speed/full throttle. Coolant temp used to go through the roof. But the engine never put a foot wrong!

It was then detuned and done another 10k/6months of start/stop driving through a very cold winter. Starting with no glowplugs at -10°c etc.

I really think the only reason that engine lasted was due to the fact it always had clean oil!
Heck I even used to run it on veg oil that was only filtered through Jcloths!

But when we got rid the engine was still going like a metranome! I really respect that engine!

I personally would rather clean cheap oil than expensive oil changed at long intervals.

Both my Focus and HDi get treated much much nicer and I do get a good mid range oil (Valvoline/Castrol etc) and generally spend about £30 on 5 litres and I change the oil every 6k/6months.
But although I have considered dropping to 5w40 Fully synth in my HDi and doing the normal 12k intervals, I feel much happier with 10w40 and 6k intervals.

Well, it's a XUD, a XUD cannot fail
Really, 12k intervals is just too much, I also change oil every 6-8k miles, but I use premium oil, as said. I agree however better change it every 5k miles and get cheap oil than every 15k miles and get premium. I wonder if these new diesels which need changing oil every 20k miles will last as long as a well kept HDi...

EDIT: I also do 80% relaxed highway driving so my oil is well happy - doing 8k on the motorway is like doing 2k on city driving engine wise.