Has anyone used 0/5W20 in an old engine?

Tried 0/5W-20 for two years in the Ranger, 4Runner and F150. A few downsides and no benefits. Now we have gone the other direction and seeing what 10w-40 does.

The Ranger didn't care outside of noisy lifters. It will get the 10w-40 with this Summer's OCI.
The F-150, an already noisy 4.9l tractor engine, was very noisy and seemed to lose power pulling a trailer against strong headwinds at highway speeds. 10w-40 seems a better fit (265,000 miles on the un-touched engine).
The 4Runner (275,000 miles on the un-touched engine) doesn't seem to care except one day when the wife, her car, got in and started it for the first time after sitting overnight. The engine made what sounded like a rod knock for about 10-15 seconds before it built oil pressure. It was parked in front of the garage and I had the door open and it caught my attention. She got out of the car and said "what the heck is that". I said I don't know but I think I have the wrong oil in it and it's getting changed.
My goal was increased fuel economy and I didn't notice any. Now we will see what the 10w-40 does. The F-150 and 4Runner are smoother and quieter on the 10w-40. Nothing scientific, just observations.
Interesting observations, thanks for sharing.

I've used a lot of 10W40 myself, the ones we get here are a semi-synthetic that's Euro A3/B4 and API SN. It's always been a smooth and reliable oil for me, and often on sale at good prices. Various flavours available: DuraBlend, Magnatec, Penrite, Shell HX7, etc.
 
If you’re too scared to do something why on earth would you do it?

And the UOA doesn’t tell you that it’s a good oil in and of itself. It tells you that it was a low wearing engine being operated under the specific conditions that were present prior to the UOA.
The price was too good to ignore and it meets the requirements for the Citroen anyway so it was worth buying.
Interesting observations, thanks for sharing.

I've used a lot of 10W40 myself, the ones we get here are a semi-synthetic that's Euro A3/B4 and API SN. It's always been a smooth and reliable oil for me, and often on sale at good prices. Various flavours available: DuraBlend, Magnatec, Penrite, Shell HX7, etc.
Also bought 3x Elf 10W40 for 7€ each at the same sale. A good old A3/B4 10W40 is the swiss army knife of oils imo.
 
A good old A3/B4 10W40 is the swiss army knife of oils imo.
I agree, around here many local mechanic shops use 10W40 A3/B4 as their default oil for a service. It's used in everything from a new Toyota Corolla to an old Ford Anglia, but probably less so now days with the growth of OEM specs like dexos. Still old faithful is being slowly upgraded from SN to SN-Plus, and maybe one day SP.

You can buy a 10W40 A3/B4 all through Europe, Australia, New Zealand, Southern Africa, etc. I'm surprised they seem to have no footprint at all in North America.

The best oil in the world? No.
A good enough oil to run all of my cars for all of their life? Yes
 
Exactly, i'm pretty sure that 10W40 is still the best seller here for people doing their own maintenance. You have the choice between 10W40 and 5W40 in A3/B4 or 5W30 in A5/B5, C2, C3. 15W40 is slowly fading away.
 
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How do you know when an oil is too thick for ultimate longevity? Surely not just cold cranking troubles.

There's simply no impairment on engine longevity to be expected when going reasonably thicker or even beyond that.
If the manufacturer specs a 5W-30 and you're using a 10W-60 that's going to affect fuel efficiency a tiny bit or even noticeably but not engine longevity. Such a thick oil may also cause cold start issues at -20°C as it surely makes life harder for your battery at this temperature. Well, a 10W-60 likely won't make much sense as it likely won't protect your engine any better than a 5W-40, but it still doesn't harm it.
The fact that I wouldn't recommend using a 10W-60 (or even a 5W-50) when the manufacturer specs a 5W-30 doesn't mean it would impair engine life. Contrarily using a 0W-20 in such a case could actually result in damaging a bearing. Typical HTHS for a 5W-30 is between 3.1 and 3.7 mPas while it's just 2.6 - 2.7 mPas for a typical 0W-20 and that's what matters.

In other words: Your question is wrong, as it assumes higher viscosity would harm.
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Interesting observations, thanks for sharing.

I've used a lot of 10W40 myself, the ones we get here are a semi-synthetic that's Euro A3/B4 and API SN. It's always been a smooth and reliable oil for me, and often on sale at good prices. Various flavours available: DuraBlend, Magnatec, Penrite, Shell HX7, etc.
The oil I'm using is the WalMart brand (SuperTech) and it's a blend. Rated at SP and no ILSAC!
 
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It is probably not really relevant since it has been specced for both 5/20 and 5/30 but the Ranger has seen everything from 0/20 to 10/30 in its life.

I've never noticed a bit of difference in anything...

Since the VW is on Ravenol and the Escape is handled by others, I'm looking to settle on something that can be used in both Rangers and the Acura... It just might be 0/40 M1...
 
How do you know when an oil is too thick for ultimate longevity? Surely not just cold cranking troubles.
I used GTX 20W-50 in my Olds Toronado Trofeo from about 120,000 miles (what it had on not when I bought it) to when I sold it with about or near 400,000 miles. Still was running like brand new. GM 3800 series 1 engine. Honestly the only reason I used 20W-50 was because the old man I bought it from was using it, I just didn't know any better back then. If I had it to do all over again, 10W-30 would've been my oil of choice.
 
I used GTX 20W-50 in my Olds Toronado Trofeo from about 120,000 miles (what it had on not when I bought it) to when I sold it with about or near 400,000 miles. Still was running like brand new. GM 3800 series 1 engine. Honestly the only reason I used 20W-50 was because the old man I bought it from was using it, I just didn't know any better back then. If I had it to do all over again, 10W-30 would've been my oil of choice.
Yeah, back then 20W50 was how you spelled oil.
 
You might want to search using Google for AEHaas old posts. He was running 0W-20 in Italian Exotics that spec 60 Grades as I recall.
 
There's simply no impairment on engine longevity to be expected when going reasonably thicker or even beyond that.
If the manufacturer specs a 5W-30 and you're using a 10W-60 that's going to affect fuel efficiency a tiny bit or even noticeably but not engine longevity. Such a thick oil may also cause cold start issues at -20°C as it surely makes life harder for your battery at this temperature. Well, a 10W-60 likely won't make much sense as it likely won't protect your engine any better than a 5W-40, but it still doesn't harm it.
The fact that I wouldn't recommend using a 10W-60 (or even a 5W-50) when the manufacturer specs a 5W-30 doesn't mean it would impair engine life. Contrarily using a 0W-20 in such a case could actually result in damaging a bearing. Typical HTHS for a 5W-30 is between 3.1 and 3.7 mPas while it's just 2.6 - 2.7 mPas for a typical 0W-20 and that's what matters.

In other words: Your question is wrong, as it assumes higher viscosity would harm.
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What are some experiences or knowledge that has lead you to these conclusions?
 
Would you mind asking more specifically? Guess all I said is widely
a consensus on this forum.
There's plenty of scientific articles, studies and dissertations publicly
available both on general lubrication and tribology and also on the
advantages and disadvantages of using thinner oils in particular. It's
also been discussed certainly more than a hundred times on Bitog.
.
 
In 1965 I bought a new Dodge Polara with the 383 cu in engine. I was told to use a thicker viscosity oil in it because of the "Soft crankshaft" that that engine had. I worked for Atlantic Richfield at the time and elected to use their 5W-20 year round. The engine ran smoothly, had plenty of power, and never gave me any problems~!
 
My only experience was M1 AFE 0W30 in place of 5W30-the xB sheared it down well into 20 territory in 7000 miles, the M1 EP 5W30 stayed in grade past 10K. Apparently the combination of long timing chains, variable valve timing, and ridiculously low gearing shears oil! Who knew? Engine suffered no ill effects, no oil burning, no warning lights, MPG stayed about the same (decent under 55 MPH, worse over 55).
 
I used M1 5-20 in a 1978 Dodge pickup with the slant 6 engine that called for 10-40 as I remember. Performed great, especially in the sub zero temps in Maine in the 70s. Only negative was the engine used a little more oil than the Valvoline 10-40.
 
2005 pontiac vibe (rebaged toyota matrix)
Called for 5w30 I never found that engine to back spec thru toyota to 5w20.
I used 0w20 and 5w20 with zero change from 5w30. I only used it because it was cheaper. The ow20 and the 5w20 would go on clearance and I could take advantage of rebates on the clearance price. Honestly though if the clearance oil had been 10w30 I probably would have bought it. My buy price for oil used to be $2/qt synthetic Or 1.25/qt conventional sometimes i could cut that price down further with rebates.
The cheap 5w20 worked in the Pontiac so i started using it in the 08 gmc with 5.3l in a ratio of 50% or less. I would buy 2 5qt mobile super synthetic jugs one in 5w20 one in 5w30. Truck took 6 car took 4.
Car got 4qts 5w20, truck would get 5qts 5w30 plus the cars leftovers. The car got about 2x per year oil changes and the truck only 1xper 12-15 months so sometimes the cars leftovers in 5w20 was 2 quarts. Things went on that way for many miles and many years nothing blew up. I towed a trailer with the truck so I didn’t feel comfortable going full 5w20 when the spec was 5w30
 
Thanks. It will be time for an oil change very soon and maybe i'll try the thin 5W30.

This car is so underpowered and i've read so much about people saying that their engines felt less sluggish with thinner oils, especially weak 4 cylinders.

The only part that makes me nervous is the fact i drive mostly on the highway around 3,000 rpm so high oil temps might be to expect.

Also, i've heard a lot about the 10 psi per 1,000 rpm rule of thumb lately and let me say that these Mercedes engines run between 20 and 30 psi at hot idle on xW40 and is always above 45 psi past 1,500 rpm or less.

Also, here is the chart from the 90's:

DSC05929_edited.JPG


Thinking about it, any modern 5W30 synthetic should be much better than a dino 5W30 from the 90's.
 
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Interesting observation:

Changed oil yesterday for the 5W30. Drove about 200 km and i don't feel or hear any difference. When i changed the oil right after 100 km of highway at 2,500 rpm on a 10c day, just after turning the engine off i touched the oil pan and i was shocked to see how cool it was to the touch.

I know this isn't very scientific but with most cars when i change the oil just after turning the engine off, the pan or the oil itself can be scorching. The oil always comes out hotter in my diesel. The pan/oil felt just as hot as my kettle when i set it on 75c and i am quite used to it. My car thermostat is set to 80c and the oil seems to be in this ballpark too.

I wish i had a thermometer handy but ambient temp seems to play a huge role just as much as driving habits despite what's been said about watercooled cars. I know MB recommends high HTHS 30, 40 and 50 grade oils but i believe this recommendation is based on driving at high speeds and the chart is the same from the smallest 1.8 4 cylinder to the biggest 6.0 V12. I am pretty sure a similar V8 or V12 would run way higher oil temps.
 
Old thread i know. just wanted to share my experience
Ok so let me first explain WHY i put 0w-20 in my clapped out 150k Dodge 3.7 engine.
I wanted to kinda clean it out a bit without using any solvents or kerosene
So i thought i would just try running a thinner oil for a while.
Unfortunately the only 0w-20 near me was full synthetic.
The engine is in pretty good shape it has a newish radiator and water pump and new oil sending unit and it only has a slight main seal seepage, normally.
I normally run Castrol 5-30 for high mileage vehicles and it works well the main seal seepage is slow enough that it doesn't drip at all.

Well two weeks ago i changed the oil and filter and went with the 0w-20 for cleaning.
Here's what happened.....
THE GOOD:
Within a couple days the oil turned dark. "That's good" , i thought "Maybe the thinner oil is cleaning things up"
Surprisingly the engine actually started running quieter not louder as i had expected.
The idle seemed to smooth out as well. Normally while sitting in the vehicle with it idling i can feel a random vibration when idling well the 0w-20 seemed to quiet that down quite a bit.
But here's the kicker.. I went from an average of 18mpg to 21mpg!
Maybe the thinner oil offered less internal resistance to the moving parts maybe the lash adjusters were able to move a little faster...maybe i gained a tad more horsepower.. Who knows.

THE BAD:
After running the oil about a week i noticed when i would restart the engine after sitting a few minutes i would get a singular PUFF of blue smoke .. Apparently some of the thinner oil was making its way past one of the valve seals. Possibly the worn seal was affected badly by the full synthetic... Who knows.
After two weeks I decided to change the oil and filter and put my regular oil back in so i crawled under the truck to change the oil and noticed that the oil pan and transmission were very much more soaked in oil and there was a drip forming. Again maybe it was the thinner oil maybe it was the full synthetic or a combination of both.

THE WEIRD:
After running the 0w-20 a couple days i started to get a P0128
Apparently the engine was now taking too long to warm up.
After the radiator and water pump change out i did a few months ago the truck does run cool but after switching to 0w-20 i noticed the the temp gauge barely gets off the the second mark when warmed up.
So i guess the thinner oil is causing less mechanical and fluid resistance in the engine keeping it cool... Again.. Who knows

So..
Would i suggest any to run 0w-20 in an older engine for cleaning purposes? .. A: Sure
Would i advise running it all the time? ... A: Absolutely NOT, not unless it was a bran new engine.

Anyway, that's my recent experience running 0w-20 in a 150k 3.7
Everyone have a good weekend.
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