Top off with a heavier oil for 0w-20?

[Insight]

For an already thin oil like 0w-20 would it make sense to top it off with something heavier, like 0w-30 or 0w-40, to make up for the fact it's thinning as you get closer to your OCI? If an engine takes 4 quarts and you have to top it off with 0.5 quarts, would you choose 0w-30 or 0w-40 to help bring it back closer to its viscosity when it was new? Let's say the OCI is 10K miles on engines with low tension rings.

 

[oldhp]

I wouldn't go 10K on the "low tension ring" engine first off. For 1/2 qt it doesn't matter. I would at least use same brand of oil for your top off.

 

[Bryanccfshr]

Depends on the location the engine etc.

How much oil are you losing between oil changes? If you get to the add mark and it’s been 5k miles you might as well change it. Something is wrong and maybe you need to try to remedy the consumption.
But I would top that 0w20 off with any 0w20 to 10w30 if it is low

 

[factorytuned2012]

if you're using oil just top off with 0w-20 if you're making it to your 10K oci just change the oil. why play chemist?

 

[Zaedock]

At what mileage do you need to add .5 qt? Mixing doesn't really matter, but just buy a 5qt jug of 0W20 in your favorite flavor and you'll have the rest for the next change.

 

[MaximumMini]

For an already thin oil like 0w-20 would it make sense to top it off with something heavier, like 0w-30 or 0w-40, to make up for the fact it's thinning as you get closer to your OCI? If an engine takes 4 quarts and you have to top it off with 0.5 quarts, would you choose 0w-30 or 0w-40 to help bring it back closer to its viscosity when it was new? Let's say the OCI is 10K miles on engines with low tension rings.

You didn't mention the year of the vehicle but most newer cars have thinner rod bearings and main bearings than years ago (in my day).
The tolerances are also tighter. All designed to cut down on CO2 emissions. If you use too thick an oil in newer engines it can actually result in lubrication starvation.

This is what I've gathered from reading a lot of forums on auto repair anyway.
Can't guarantee the validity.

 

[TurboZedd-R]

If it's a long drain oil it should be within spec at 10k and doesn't need help with viscosity. You can also do changes at 7500 miles of worried about it.

 

[Kira]

Details, please.
It sounds like you're trying to make up a "rule of thumb".

 

[OVERKILL]

You didn't mention the year of the vehicle but most newer cars have thinner rod bearings and main bearings than years ago (in my day).
The tolerances are also tighter. All designed to cut down on CO2 emissions. If you use too thick an oil in newer engines it can actually result in lubrication starvation.

This is what I've gathered from reading a lot of forums on auto repair anyway.
Can't guarantee the validity.

No, bearing clearances are about the same as they've always been. Bearings have gotten wider, to allow the use of thinner oils. If a heavier oil resulted in lubrication starvation, every engine in Winnipeg would have failed by now, given that temperature has the largest impact on viscosity.

 

[OVERKILL]

For an already thin oil like 0w-20 would it make sense to top it off with something heavier, like 0w-30 or 0w-40, to make up for the fact it's thinning as you get closer to your OCI? If an engine takes 4 quarts and you have to top it off with 0.5 quarts, would you choose 0w-30 or 0w-40 to help bring it back closer to its viscosity when it was new? Let's say the OCI is 10K miles on engines with low tension rings.

Pretty much every engine has low tension rings at this juncture including my two HEMI's that don't fuel dilute or use any oil, so you are going to have to be far more specific as to what you are trying to address and what the equipment is.

 

[MaximumMini]

No, bearing clearances are about the same as they've always been. Bearings have gotten wider, to allow the use of thinner oils. If a heavier oil resulted in lubrication starvation, every engine in Winnipeg would have failed by now, given that temperature has the largest impact on viscosity.

Thanks. Knowledge sponge here.
Very good point. I live where it never gets cold so I forget that aspect

Just to be clear then....using 10w-30 in an engine calling for 0w-20 would cause no problems ?

 

[TiGeo]

*cracks knuckes* as I start preparing a bingo card.

 

[kschachn]

Thanks. Knowledge sponge here.
Very good point. I live where it never gets cold so I forget that aspect

Just to be clear then....using 10w-30 in an engine calling for 0w-20 would cause no problems ?

It doesn’t have to get that cold to greatly increase the viscosity beyond what it is at operating temperature.

And the answer to your question is no. You can use a -40 grade if you wish. As long as the winter rating is appropriate for your starting temperatures. An oil (any oil) with a 10W winter rating is appropriate for temperatures down to about 0F.

 

[OVERKILL]

It doesn’t have to get that cold to greatly increase the viscosity beyond what it is at operating temperature.

And the answer to your question is no. You can use a -40 grade if you wish. As long as the winter rating is appropriate for your starting temperatures. An oil (any oil) with a 10W winter rating is appropriate for temperatures down to about 0F.

This.

 

[MaximumMini]

Great. This makes me feel better since last year, I added 10w-30 to one of my vehicles that called for 0w-20 and felt awful that I may have caused some damage.

Big relief.
It's so easy for people like me to get misled by internet information.

 

[ARCOgraphite]

I find modern, low mileage engines don't run well if you stray too far from the oil cap recommended viscosity.
And I have a lot of first hand experience here to form this opinion.

But I have no issue topping off a modest oil burner with a 1/2 litre of an ACEA Porsche spec A40 approval oil

Read that as the previous version of M1 0w40 FS

 

[ARCOgraphite]

Great. This makes me feel better since last year, I added 10w-30 to one of my vehicles that called for 0w-20 and felt awful that I may have caused some damage.

Big relief.
It's so easy for people like me to get misled by internet information.

Not internet information. Call it non-professional, inexperienced, shade-tree "wrencher" advice.

You have to be aware of who you are conversing with, and discard the chaff from the seed.

Same goes to advice on this forum - but there will be quick checks to faulty or misleading advice around here. Usually.

 

[RDY4WAR]

For an already thin oil like 0w-20 would it make sense to top it off with something heavier, like 0w-30 or 0w-40, to make up for the fact it's thinning as you get closer to your OCI? If an engine takes 4 quarts and you have to top it off with 0.5 quarts, would you choose 0w-30 or 0w-40 to help bring it back closer to its viscosity when it was new? Let's say the OCI is 10K miles on engines with low tension rings.

Simply topping off with 0W-20 will bring viscosity back up slightly. Unless I knew for sure that the 0W-30 and 0W-40 variant of that specific oil brand and series uses the same additive chemistry, I wouldn't bother. If you want to go with a 0W-30 at the next oil change, do that. You could also use a better quality 0W-20 that won't shear much or at all. It'll still dilute down from fuel (if your engine is prone to doing so), but you won't have shear on top of that.

 

[MaximumMini]

Not internet information. Call it non-professional, inexperienced, shade-tree "wrencher" advice.

You have to be aware of who you are conversing with, and discard the chaff from the seed.

Same goes to advice on this forum - but there will be quick checks to faulty or misleading advice around here. Usually.

I'm not a professional mechanic. Just learned as I go.
I LOVE to be schooled. If I'm a moron on a certain topic then I think those willing to teach me otherwise are doing me a favor.
There is no one who can't learn from others.
My ego be ****ed. I just want to learn to do things right

 

[Titan]

I'm not a professional mechanic. Just learned as I go.
I LOVE to be schooled. If I'm a moron on a certain topic then I think those willing to teach me otherwise are doing me a favor.
There is no one who can't learn from others.
My ego be ****ed. I just want to learn to do things right

Everyone is ignorant about many things. That's a fact. Being willing to learn is what allows you to gain knowledge. If everyone could approach topics this way, we'd be better off, but so many want to think what they think is "right". "I don't know, but would like to find out" was the beginning of Science. Many things can be tested...those that can be tested can be verified or rejected by following Scientific Method. Otherwise, you're operating in the realm of religion or politics, where "my point of view is just as good as your point of view", even if both points of view are wrong.