Topping up a fill with a different brand

[dwasifar]

Inconveniently, two of our cars take a little more than a five quart jug to fill. They take 5.5 quarts. So rather than buying an expensive single quart and still having a partial bottle kicking around, I just keep a jug labeled Partial to top off that extra pint or so with.

That's fine, but sometimes it works out they're different brands. (Like say I found a sale on Brand B but my partial jug is Brand A.). I don't really worry about that, but I wonder how many of you guys do. Opinions?

 

[JayhawkRoy]

Put me in the "I don't worry about that" category.

 

[racer12306]

I have bought two 5qt containers for a 6qt engine. Then next time bought a single 5qt and so on until I needed to buy two 5 qts again.

I prefer to have all the same oil in the sump.

 

[ARCOgraphite]

Professional advice: Use same oil for topoff .

Personally, I used to keep some oil that I thought would work well as a "booster" or had "magical" properties. Most of the time there was no clash - the car ran smoother, and UOA were the best you would read on BITOG at ~1ppm per 1k mi combined average of all "wear" metals.
Had used Castrol Magnatec 5W20 SS- which is unavailable now. Today I would use M1 Supercar 0W40 - in the past it was M1 FS 0W40. I Haven't tried ESP 0W30 which is a candidate. - Arco

 

[duck__dodgers]

when you drain the oil, on most (all?) cars, you never get 100% of the old oil out.

we all have been mixing 80% - 90% brand 1 with brand 2, every time after a brand switch. theoretically, every car still has an infinitely small amount of factory-fill oil in it, lol

 

[JavierH19]

Your engine has a wet and dry fill. When you drain what seems to be everything out of the engine there's 1-2 quarts left sometimes 3 in some engines so you're always mixing oil.

 

[Owen Lucas]

Unless it’s a high performance car, like hyper-car territory or Indy / nascar. I’d say it doesn’t matter as long as it’s the correct weight and rating .

 

[RyanY]

If one of my cars takes more than a 5qt jug, I rarely use the same oil for an entire fill during the oil change, let alone for top offs!

For other people I typically use the same oil for the entire fill unless they tell me to do otherwise. They get what they pay me for.

 

[Stelth]

Your engine has a wet and dry fill. When you drain what seems to be everything out of the engine there's 1-2 quarts left sometimes 3 in some engines so you're always mixing oil.

I don’t think so. At least not on any car I’ve ever had. Where would this oil be? If you pour oil into the fill hole, it runs down into the oil pan. If you remove the drain plug, it runs out. There may be a few ounces hanging out on top of the head(s), in the lifter valley (if you have one), but I doubt it’s half a pint, let alone quarts.

 

[ecotourist]

Inconveniently, two of our cars take a little more than a five quart jug to fill. They take 5.5 quarts. So rather than buying an expensive single quart and still having a partial bottle kicking around, I just keep a jug labeled Partial to top off that extra pint or so with.

That's fine, but sometimes it works out they're different brands. (Like say I found a sale on Brand B but my partial jug is Brand A.). I don't really worry about that, but I wonder how many of you guys do. Opinions?

I use partial jugs of the same oil to complete the fill. I would buy 3 jugs of 5 quarts each and after changing the oil on both vehicles would end up with 4 quarts left in the 3rd jug. That would make for a good start on the next change.

I try to stick with the same oil, Castrol Syntec in my case. I don't think it matters very much which oil you choose.

I always start the new pour from the left over jug. The left over oil is always left over from the last change.

 

[JavierH19]

I don’t think so. At least not on any car I’ve ever had. Where would this oil be? If you pour oil into the fill hole, it runs down into the oil pan. If you remove the drain plug, it runs out. There may be a few ounces hanging out on top of the head(s), in the lifter valley (if you have one), but I doubt it’s half a pint, let alone quarts.

P

Thread 'Oil Dry Fill vs Service Fill'

Sep 9, 2017

Can anyone tell me what's the difference between a dry oil fil and a Service oil fill !
Thanks

• Pelican
• Replies: 12
• Forum: Passenger Car Motor Oil (PCMO) - Gasoline Vehicles

You're welcome to look up "wet and dry fill" first

Small 4 cyls have a 1 quart difference. The larger the higher. Someone stated their 8 quart tundra takes 1.8qts more dry fill. Wet fill is also referred to as service fill and dry fill is also referred to as initial/rebuild/overhaul fill. I imagine some big high performance engine like a v10/12 that takes over 10 quarts wet and has a dry sump meaning tubing, pumps, and other things can have 3 quarts or more difference.

 

[Nessism1]

I mix and match oils regularly. Clean out the remnants left behind on the bottom of multiple containers. Brand doesn't matter, and viscosity doesn't either, as long as it's within a grade or so of what you are targeting.

 

[cheesepuffs2]

I don’t think so. At least not on any car I’ve ever had. Where would this oil be? If you pour oil into the fill hole, it runs down into the oil pan. If you remove the drain plug, it runs out. There may be a few ounces hanging out on top of the head(s), in the lifter valley (if you have one), but I doubt it’s half a pint, let alone quarts.

There may not be "quarts" but there are several ounces of residual oil clinging to every surface inside the engine. The "dry fill vs wet fill" capacities are different for a reason. Engines do hold significant enough amounts of oil even when drained from the pan.

 

[JavierH19]

There may not be "quarts" but there are several ounces of residual oil clinging to every surface inside the engine. The "dry fill vs wet fill" capacities are different for a reason. Engines do hold significant enough amounts of oil even when drained from the pan.

P

Thread 'Oil Dry Fill vs Service Fill'

Sep 9, 2017

Can anyone tell me what's the difference between a dry oil fil and a Service oil fill !
Thanks

• Pelican
• Replies: 12
• Forum: Passenger Car Motor Oil (PCMO) - Gasoline Vehicles

 

[JeffKeryk]

The world has been doing Frankenbrews for billions of years. I have not heard of issues...

 

[gfh77665]

Zero issue. 10's of millions of vehicles have had brand mixes and never a problem. A top off of a 0.5qt. doesn't even make it a real mix, in my opinion anyway.

 

[TomYoung]

when you drain the oil, on most (all?) cars, you never get 100% of the old oil out.

we all have been mixing 80% - 90% brand 1 with brand 2, every time after a brand switch. theoretically, every car still has an infinitely small amount of factory-fill oil in it, lol

No we haven't. In most cars, your are getting well north of 95% of the old oil out by draining. Your 80-90% suggestion is just plain wrong.

 

[JavierH19]

API requires oil be compatible. And yeah I know it's not preferred to mix but who cares if you mix a quart of supertech syn 5w-30 with a quart of regular mobil 5w-30, or m1 5w-40 with a quart of castrol 5w-40 for example.

 

[crashz]

As other have said, its not a big deal. I like to try to stick to the same brand if I mix, but not really a huge issue. Unless you are using something totally different like M1 0W-40 with a top off of canola oil. That's where I draw the line.

 

[Stelth]

P

Thread 'Oil Dry Fill vs Service Fill'

Sep 9, 2017

Can anyone tell me what's the difference between a dry oil fil and a Service oil fill !
Thanks

• Pelican
• Replies: 12
• Forum: Passenger Car Motor Oil (PCMO) - Gasoline Vehicles

You're welcome to look up "wet and dry fill" first

Small 4 cyls have a 1 quart difference. The larger the higher. Someone stated their 8 quart tundra takes 1.8qts more dry fill. Wet fill is also referred to as service fill and dry fill is also referred to as initial/rebuild/overhaul fill. I imagine some big high performance engine like a v10/12 that takes over 10 quarts wet and has a dry sump meaning tubing, pumps, and other things can have 3 quarts or more difference.

There may not be "quarts" but there are several ounces of residual oil clinging to every surface inside the engine. The "dry fill vs wet fill" capacities are different for a reason. Engines do hold significant enough amounts of oil even when drained from the pan.

No question there’s residual oil. Enough to throw off a UOA. A little. But if you disassemble, let’s say, a 2003 Hyundai 2.0, an engine I have experience with, you’re not going to find any quarts of oil. Everything will be oily, of course, and there will be some liquid oil on top of the head, but a quart? Unlikely. A pushrod V-8 will have more, what with oil in the lifters, lifter valley, having two heads, etc. but I’m not thinking half a gallon.

They used to tell you you’ll need an extra quart for the filter, too. That might be pretty close if you’re using a PH-8A, but not with my Hyundai, Nissan, or Toyota vehicles.