Engine oil, mixing brands/grades?
Discussion
Going to do an oil change on my car, was about to order the oil and filter but then remembered I had some left of the correct 20w 50 Castrol from previous changes and top ups, about 2.5/3L.
So, do I buy a fresh 5L pack or use what I have and some of the other Synthentic oil, which is a VAG/Merc spec Castrol 20 W 30 hanging round.
Will it make any actual difference, car is a 2015 Fiesta ST.
Its not the cash, but it is like £40, its just partly down to decluttering my garage with its selection of 9 or 10 containers of oil.
My thoughts are, it will be fine, its fresh, clean fully synthetic oil, it does maybe 5k a year, so will likely do it anyway, just interested as to any thoughts as to why it may be a bad idea, you take a car to a garage and they tend to plonk whatever they have in.
Found some from 2005, 1L top up containers, does engine oil ever go off ? That will do for the mower.
So, do I buy a fresh 5L pack or use what I have and some of the other Synthentic oil, which is a VAG/Merc spec Castrol 20 W 30 hanging round.
Will it make any actual difference, car is a 2015 Fiesta ST.
Its not the cash, but it is like £40, its just partly down to decluttering my garage with its selection of 9 or 10 containers of oil.
My thoughts are, it will be fine, its fresh, clean fully synthetic oil, it does maybe 5k a year, so will likely do it anyway, just interested as to any thoughts as to why it may be a bad idea, you take a car to a garage and they tend to plonk whatever they have in.
Found some from 2005, 1L top up containers, does engine oil ever go off ? That will do for the mower.
E90_M3Ross said:
Just use the correct grade and spec for the car. It would probably be fine, but I personally wouldn't use anything other than manufacturer approved and recommended.
Nah, its getting whats there, its a ten year old Fiesta, just interested to what could possibly happen rather than "Just do it m'kay".Ford thought the Mustang MachE was a good idea so not that bothered what they say.
20/50w? Did you mean to type 5/20w?
I have mixed oils from different manufacturers in the past but tend to stick to the same viscosity/ACEA grade. For a routine oil change in your Fiesta I wouldn't mix 5/20w with an appreciable amount of 5/30w. I'd chance a small top-up if I had to, but no more than 1 litre (assuming they both met the same classification).
I have mixed oils from different manufacturers in the past but tend to stick to the same viscosity/ACEA grade. For a routine oil change in your Fiesta I wouldn't mix 5/20w with an appreciable amount of 5/30w. I'd chance a small top-up if I had to, but no more than 1 litre (assuming they both met the same classification).
jhonn said:
20/50w? Did you mean to type 5/20w?
I have mixed oils from different manufacturers in the past but tend to stick to the same viscosity/ACEA grade. For a routine oil change in your Fiesta I wouldn't mix 5/20w with an appreciable amount of 5/30w. I'd chance a small top-up if I had to, but no more than 1 litre (assuming they both met the same classification).
Why though ?I have mixed oils from different manufacturers in the past but tend to stick to the same viscosity/ACEA grade. For a routine oil change in your Fiesta I wouldn't mix 5/20w with an appreciable amount of 5/30w. I'd chance a small top-up if I had to, but no more than 1 litre (assuming they both met the same classification).
What could happen ?
J4CKO said:
jhonn said:
20/50w? Did you mean to type 5/20w?
I have mixed oils from different manufacturers in the past but tend to stick to the same viscosity/ACEA grade. For a routine oil change in your Fiesta I wouldn't mix 5/20w with an appreciable amount of 5/30w. I'd chance a small top-up if I had to, but no more than 1 litre (assuming they both met the same classification).
Why though ?I have mixed oils from different manufacturers in the past but tend to stick to the same viscosity/ACEA grade. For a routine oil change in your Fiesta I wouldn't mix 5/20w with an appreciable amount of 5/30w. I'd chance a small top-up if I had to, but no more than 1 litre (assuming they both met the same classification).
What could happen ?
J4CKO said:
Why though ?
What could happen ?
There's a big difference between 20/50w (usually used in much older cars) and a modern 5/20w oil. Using a thicker (heavier viscosity oil) can have a detrimental effect on your engine and fuel economy. It can affect engine start-up wear, turbo and oil pump life, amongst other things.What could happen ?
Isn't the MK7 ST supposed to have a really thin oil grade like 0W-20 or 5W-20? I had one and I remember the oil being quite a specific type and weight. It had a lime green appearance new out of the bottle.
Given that yours is also remapped I would side with the correct grade as recommended by the manual and chuck the older stuff in the recycling center. £40 of oil or £6000+ of new engine? It's an easy one for me.
Given that yours is also remapped I would side with the correct grade as recommended by the manual and chuck the older stuff in the recycling center. £40 of oil or £6000+ of new engine? It's an easy one for me.
J4CKO said:
jhonn said:
20/50w? Did you mean to type 5/20w?
I have mixed oils from different manufacturers in the past but tend to stick to the same viscosity/ACEA grade. For a routine oil change in your Fiesta I wouldn't mix 5/20w with an appreciable amount of 5/30w. I'd chance a small top-up if I had to, but no more than 1 litre (assuming they both met the same classification).
Why though ?I have mixed oils from different manufacturers in the past but tend to stick to the same viscosity/ACEA grade. For a routine oil change in your Fiesta I wouldn't mix 5/20w with an appreciable amount of 5/30w. I'd chance a small top-up if I had to, but no more than 1 litre (assuming they both met the same classification).
What could happen ?
The smaller the first number (the W number) the less viscous / easier flowing the oil is when cold
The smaller the second number the less viscous / easier flowing the oil is when hot.
The viscosity over the normal range of operating temperature will be between the two numbers, so the smaller the "gap", the less the viscosity changes over its temperature range. For example, a 5W/20 will have much more uniform viscosity over its temperature range than a 20W/50.
The engine's lubrication system will be designed to provide optimum oil pressure with oil of the recommended viscosity. If you deviate from this, it could cause the oil pressure to drop out of spec.
In reality, 20 to 30 would probably make no appreciable difference.
Think OP needs to check whether the oil he has is 5w20 or 20w50.
20w50 hasn't been specified in most cars in the last 30+ years. It was traditionally used in either very, very old cars (like pre-1950s) or pretty knackered 70s and 80s cars that really needed new piston rings etc and were consuming too much of the originally-required oil, so drivers who were skint would put thicker oil in that would get burned up slower...
Modern engines tend to work to tighter tolerances and require much thinner oil to protect stuff like the turbocharger, which weren't very common in the 70s...
20w50 hasn't been specified in most cars in the last 30+ years. It was traditionally used in either very, very old cars (like pre-1950s) or pretty knackered 70s and 80s cars that really needed new piston rings etc and were consuming too much of the originally-required oil, so drivers who were skint would put thicker oil in that would get burned up slower...
Modern engines tend to work to tighter tolerances and require much thinner oil to protect stuff like the turbocharger, which weren't very common in the 70s...
SAS Tom said:
I wouldn’t risk anything but the correct oil on an ecoboom. Having said that it’ll more than likely blow either way.
Though the engine is listed as an Ecoboom/boost, its not the ones that typically give trouble being the 1.6 four, and not the 1.0 triple, these are typically pretty reliable, and its running 50 percent more power than normal as well, and has been for a couple of years, and a track day. J4CKO said:
SAS Tom said:
I wouldn’t risk anything but the correct oil on an ecoboom. Having said that it’ll more than likely blow either way.
Though the engine is listed as an Ecoboom/boost, its not the ones that typically give trouble being the 1.6 four, and not the 1.0 triple, these are typically pretty reliable, and its running 50 percent more power than normal as well, and has been for a couple of years, and a track day. I’ve personally seen one that has blown the ringlands out of a piston.
Hydraulic tappets ? Can't recall which engine, local Ford dealer continued with same oil they always used in a newly introduced engine, cue many non cold start breakdowns. Hydraulic tappets holding valves open due to incorrect grade.
Might've been the Mondeo ?
Might've been the Mondeo ?
Edited by Maxdecel on Tuesday 26th March 22:56
Edited by Maxdecel on Tuesday 26th March 22:58
as long as its not the ecoboost oil or the vw spec oil getting mixed with normal oil
Ie the same spec just a diferent brand i wouldnt bother ive done it loads of times
i only change the filter every two or three changes as well, because i cant be bothered with the mess,
i usally buy a 10 or 20l container and do it once a year regardless with that pela pump thing and ive never had any problems
Ie the same spec just a diferent brand i wouldnt bother ive done it loads of times
i only change the filter every two or three changes as well, because i cant be bothered with the mess,
i usally buy a 10 or 20l container and do it once a year regardless with that pela pump thing and ive never had any problems
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