Why You Should Change Your Oil Frequently

[oscar]

I've noticed recently that a lot of people often neglect to change their oil at the stated intervals as recommended by the respective manufacturers.

In my oppinion, to understand it all you will need to have a fair knowledge of the ICE and emissions. On the power stroke, the expanding gasses pushing the piston down will leak past the pistons compression rings and as these are not a perfect seal, some unburned fuel and water (products of incomplete combustion) make their way into the the crankcase and mix with the oil in your sump. Over time, to keep it basic your oil will mix with this moisture and fuel which creates ''gunk'' which will collect at the bottom of your sump which is fine if you stick to the manufacturers recommended oil change intervals, the gunk will come out with the oil no bother. If you exceed this interval, the engine oil will get acidic after long use and will also lose the viscosity properties that are required to keep surfaces lubricated. The oil will also cause the filter to become less efficient and the bypass valve will open and the oil will no longer go through the filter and all the little contaminants will continue going through the engine causing main bearing surfaces and other metal-to-metal surfaces to "grind" to failure. Bearings will wear causing a larger gap between the crank surfaces and the bearings and the oil pressure will drop, then other parts will fail. The vital moment in every engine is when you start a cold engine. If there is a lot of contaminants settled in the bottom of the oil sump (which is where the oil pick-up is), all the solid contaminants will pass through the engine, again causing bearing surface failure.

This gunk will crystalise around the crankshaft, the camshaft and all their associated bearings making cold starts close to impossible. Eventually your big end bearings will have no lubrication, as well as your cylinder walls meaning that the piston rings will create so much heat due to the lack of lubrication as they move up and down on their respective strokes that the piston rings will basically weld themselves to the cylinder walls and to the piston crown itself in the worst case scenario.


I was always taught to change oil every 5,000 miles regardless of the manufacturers recommendations to prolong the working life of the engine. If we assume 5L of good oil costs around 35 pounds making that 3,500 pennies over 5,000 miles this equates to 1.4 pence per mile in oil costs.

 

[Spitfire1]

So why do Renault now set your service intervals at 20K, surely the oil used in modern engines is supposed to last that long, also I have a 4 year service plan with the car so Renault change that FOC. What happens if you change your oil with a different manufacturer at say 10K how will Renault veiw that???

I would certainly consider changing my oil & filter at 10K which I consider to be the norm, maybe I'll just do it based on using the same oil as Renault and not tell them. What make do Renault use ???

 

[oscar]

let's be brutally truthful here, the moment that warranty ends is when the maintenance and servicing of the vehicle is on the shoulders of the owners down the years and there is a reason that renault says 20k. renault do not want you to buy one car that is going to last you 20 years before it dies, renault wants to sell you a new car every three years and for that to happen they need to reduce the life of their cars. it's not a sinister conspiracy or anything, it's just how it is. everything on this planet is made to fail so that you are a repeat customer. for this to happen they need to be generous on the servicing schedule and this won't effect the car whilst it's a few years old but as it approaches 10 years old it will begin to run rougher and rougher until it needs new big end bearings and other such things ......... compare that to the guy who changes his oil every 3-5,000 miles and that's the guy who's running his renault 5 turbo right now on the original engine 20-30 years later.

even with your best engine oils, they start to decay within the first 1,000 miles. fill your car up with mobil 1, 1k miles later pull a sample out take a PH reading and you'll cry. this is down to crankcase gases slowly being absorbed into the oil even when the PCV is fully operational. essentially it's all a marketing ploy to ensure that you will be a return customer because people with new cars don't need to worry about oil changes and engine wear, that's only folk with much older models who need to worry.

also, renault uses ELF oil which is a brand of TOTAL. i don't rate it highly, renault only recommends it because it's got a manufacturing partnership with them meaning they get dirty cheap oil in return for renaults thumbs up so to speak.

 

[AS_BO]

let's be brutally truthful here, the moment that warranty ends is when the maintenance and servicing of the vehicle is on the shoulders of the owners down the years and there is a reason that renault says 20k. renault do not want you to buy one car that is going to last you 20 years before it dies, renault wants to sell you a new car every three years and for that to happen they need to reduce the life of their cars. it's not a sinister conspiracy or anything, it's just how it is. everything on this planet is made to fail so that you are a repeat customer. for this to happen they need to be generous on the servicing schedule and this won't effect the car whilst it's a few years old but as it approaches 10 years old it will begin to run rougher and rougher until it needs new big end bearings and other such things ......... compare that to the guy who changes his oil every 3-5,000 miles and that's the guy who's running his renault 5 turbo right now on the original engine 20-30 years later.

even with your best engine oils, they start to decay within the first 1,000 miles. fill your car up with mobil 1, 1k miles later pull a sample out take a PH reading and you'll cry. this is down to crankcase gases slowly being absorbed into the oil even when the PCV is fully operational. essentially it's all a marketing ploy to ensure that you will be a return customer because people with new cars don't need to worry about oil changes and engine wear, that's only folk with much older models who need to worry.

also, renault uses ELF oil which is a brand of TOTAL. i don't rate it highly, renault only recommends it because it's got a manufacturing partnership with them meaning they get dirty cheap oil in return for renaults thumbs up so to speak.

+1 to this Dave. I know we've spoken about this before and I'm happy to second this. I've been around a lot of experienced mechanics and engine builders/Motorsports engineers and you really can't put a price on decent oil with regular changes. The benefits are well recorded with regards to overall performance, longevity of engine parts, emissions, fuel consumption the list goes on and on. Gearbox oil is another one which is often overlooked as something that can wait. Definitely not, it's just as important as engine oil in my opinion and is often the weak link in the drivetrain because of that very reason - poor maintenance.

 

[Guesstimator]

always changed engine oil every 10000km (roughly 6200 miles), also considering i often go to trackdays!!!
I also stick with the recommended oil manufacturer, after making sure that it is indeed is the oil with which the dyno durability tests have been done (little insider info here is needed though).

a little off topic but I'm also a big fan of V-Power...stripped a couple of engines that ran only on this, and the condition of the ducts, combustion chamber and pistons was always impeccable!

 

[oscar]

AS_BO - you said just about everything i forgot to say and i am embarassed to admit that i forgot to mention the transmission fluid. you'd be amazed how how many people neglect their transmissions to the point where it's not engaging gears anymore and they come in thinking it's the end of the world > start with a simple fluid change and bingo, everything's just fantastic again then you ask them when did they last change their transmission fluid ''does that not get changed with oil?... i thought it did'' i wonder if there are any mechanics out there who actually care about their customers. it's the mechanics duty to inform customers that their car needs this or that done whilst monitoring mileage so that you can make the customer aware that a certain major servicing point is approaching such as timing belts / auxiliary belts / transmission fluid changes. it's not the customer / car owners fault that they don't understand how a car works and maintenance schedules in the real world.



guesstimator - as i mentioned earlier, the only reason that renault recommends ELF oil is because at the point of manufacturing, Renault has a contract with TOTAL who own ELF to supply all their range with certain oils meaning that renault gets oil which meets it's requirements for as cheap as it can possibly get. the oils themselves contain additives for anti-corrosion, anti-foaming detergents and a whole host of other additives. you will find that your mobil 1's, castrols, petronas oils all have the same additives and then some more to protect your engine further. the difference is massive. take my word for it, and ask any mechanic their oppinion on ELF oil and if they would ever recommend it over say mobil 1 / castrol / petronas / lucas oils. the difference in quality is staggering, if we filled two identical cars up with elf and then one with mobil 1 and sent them out into the real world to come back at 3,000k miles so that we could take a sample... the differences would be gobsmacking. the only oils renault will sell to you are elf and this other crap which is recycled, i can't even remember what it's called but it's absolute junk. it's the same recycled crap that you get in halfords for cheap as halfords own brand.

 

[Martin_172]

I change mine at the required interval as specified by the manufacturer as when I come to sell the car or have any warranty issues this is what people look for. sure if someone comes to view my car and ive done 5k oil changes this is a benefit to them, will they give me an extra £500 for the car? no.

we run a fleet of driving school cars, Renault Twingo 1.2 16v Dynamiques, we used to keep them for 3yrs, 200k miles but now we only keep them 2yrs and around 140k due to the cars not standing up well enough to this millage! however the one component we have never had any issues with is engines (bar a premature cambelt failure at low miles!)

if we were to do 5k changes on these at say £50 a change your talking £1400 in oil changes in 2 years compaired to £400 for the manufacturers specification.

id say only 1% of owners keep a car long enough to see any benefit from regular oil changes and even at that, by the time they have any sort of mechanical engine failure a rebuild to have a fresh engine will be cheaper than what has been spent on oil changes over the last X amount of years/miles

 

[oscar]

with an engine rebuild you are breaking the costs down roughly by
removal and refit > 500 - 8-- or therabouts depending on labour rates and chosen workshop
engine rebuild itself > around the same price. pistons, oil and compression rings, full set of valves, valve stems + the hydraulic parts of the valvetrain itself and big end bearings so on so forth.

if you conclude 5L of oil at public prices costs 25-40 pounds if we say 30, that's 150,000 miles divided by 5k oil changes = 30 oil changes. times this by the cost of the oil say £30. the assumption is that people do their own oil changes, 30 x 30 = £900. the point is longevity of the engine itself and getting the most out of an engine and from experience a proper engine rebuild certainly does not come cheap. a simple engine swap for a lower mileage engine could be had for much cheaper, which again stems to the entire point of this thread as you cannot be sure of the condition of the internals of the engine you've just replaced.

point is really theory based, not many people will have their twingo's like me when it's at 200k miles and a classic. i definitely intend on keeping mines until mother nature gets the better of her lol

 

[Rob_McLav]

Damn I always thought elf was good :/ time for an oil change then!!

 

[rstaylor]

Good info here, i've always thought 20k or 2 years was way too long an interval for an oil and filter change

 

[Dazza1]

I change my oil and filter every 6 months.

 

[Dazza1]

I change my oil and filter every 6 months.

 

[oscar]

best thing you can do dazza when you get bargain 5L prices of triple qx and sometimes the occasional £14 5L of mobil 1 from tesco you should stack up on those oils so that you can do your 6 month / 12 month oil changes with good oil, not cheap oil. triple qx isn't the best oil, or the worst really but when you're changing it like above then it doesn't really matter because the oil will still be in fairly good condition when you drain it to renew it which shows your engines in tip top health thanks to your oil changes, with no gunk in the oill or mess! oil filters important too as our little twingos are all full flow systems, bad things happen when oil filters get blocked!

 

[AS_BO]

best thing you can do dazza when you get bargain 5L prices of triple qx and sometimes the occasional £14 5L of mobil 1 from tesco you should stack up on those oils so that you can do your 6 month / 12 month oil changes with good oil, not cheap oil. triple qx isn't the best oil, or the worst really but when you're changing it like above then it doesn't really matter because the oil will still be in fairly good condition when you drain it to renew it which shows your engines in tip top health thanks to your oil changes, with no gunk in the oill or mess! oil filters important too as our little twingos are all full flow systems, bad things happen when oil filters get blocked!

Glad you mentioned oil filters Dave, do you know how much a Renault OE filter is for the 133? I'm gonna drop mine once I get some triple qx. And do you reckon Renault would notice that I've done the oil come November service time? I reckon I will have done about another 4K then.

 

[oscar]

Glad you mentioned oil filters Dave, do you know how much a Renault OE filter is for the 133? I'm gonna drop mine once I get some triple qx. And do you reckon Renault would notice that I've done the oil come November service time? I reckon I will have done about another 4K then

.
two things to take into consideration with your situation mate is that you're still in warranty period aren't you? in which case your only obligation is to meet renaults standards for oil which is RN0700 or something of the sorts. essentially you've met that standard so your warrantys good. and on the second note, even if you didn't use the recommended oil standard then you'd struggle to find a chemical engineer nevermind a blooming mechanic who could spot a difference between certain oils lol i know i sure as hell couldn't spot the wrong oil out!


the oil filters peanuts even from renault. change of a 20 note certainly. borderline on change from a 10 note

 

[AS_BO]

Glad you mentioned oil filters Dave, do you know how much a Renault OE filter is for the 133? I'm gonna drop mine once I get some triple qx. And do you reckon Renault would notice that I've done the oil come November service time? I reckon I will have done about another 4K then

.
two things to take into consideration with your situation mate is that you're still in warranty period aren't you? in which case your only obligation is to meet renaults standards for oil which is RN0700 or something of the sorts. essentially you've met that standard so your warrantys good. and on the second note, even if you didn't use the recommended oil standard then you'd struggle to find a chemical engineer nevermind a blooming mechanic who could spot a difference between certain oils lol i know i sure as hell couldn't spot the wrong oil out!


the oil filters peanuts even from renault. change of a 20 note certainly. borderline on change from a 10 note

Schweet cheers dude. The triple QX stuff is better spec'd than the elf shite anyway isn't it?

 

[oscar]

in my oppinion elf is junk. when i was still at renault, i always noticed that in the same 12,000 oil change period the differences between an elf oil coming out and a good oil coming out. the elf oil ended up black and looked sorry for itself which to me indicates a crap oil, whereas after warranty period has expired when customers specified a better oil such as mobil 1 / lucas so on so forth the colour and condition of the oil was noticeably better. triple qx would fall in the middle ground of oils from experience in using it. the beauty with using triple qx is that you don't need to care about premium oils, as you'll be changing the oil frequently so it'll never get to the stage where the oils past it's best.

i couldn't put forward any information as to why elf is junk though, i suppose you can only go by what you've seen in your own experiences