Why The Dislike For 20W-50?

[Red91]

Just curious....why is 20W-50 so unpopular among most members on this board? I understand that things change, and modern car makers are calling for thinner oils, but why is 20W-50 spoken of with contempt in older cars and applications? It seems it was very popular from the 80's up until the middle of the last decade. I've used it in the past and even have some I purchased recently for top off. I find no fault with it, in the right application. These days I use QSGB 5W-30, but my truck is burning some oil, and next time it needs a quart, it's getting QSGB 20W-50.

 

[19jacobob93]

As long as you live in areas that don't get overly cold, I reckon 20w50 is fine depending on application.
It doesn't get much below freezing around here but we had a 2001 Mitsubishi 3.5 that burnt a huge amount if oil, the sump had 20w50 Maxlife + a full bottle of Lucas oil stabilizer and that thing always started fine in winter. For an old v8 I wouldn't hesitate to use it.
The reason why people hate it on here is because it gives poor fuel economy over thinner oils and takes longer to reach the top end. I personally wouldn't use it in my car, anything fairly new or if you live somewhere that regularly gets below 15F

 

[Nick1994]

Because it's unnecessary on cars these days unless they're burning a ridiculous amount of oil or unless you're using it in a motorcycle or an air cooled VW. And people in the 80s didn't know much about oil, there was no BITOG for them to figure things out and find out what the better viscosity is. People didn't do UOA's and I imagine they just went "this one says motor oil' on the can and bought it. Back in the day the mentality was the thicker oil lubricates better. Not true.

 

[MalfunctionProne]

Nothing "wrong" with it, it's just stupid now.

 

[MalfunctionProne]

Originally Posted By: Red91
Just curious....why is 20W-50 so unpopular among most members on this board? I understand that things change, and modern car makers are calling for thinner oils, but why is 20W-50 spoken of with contempt in older cars and applications? It seems it was very popular from the 80's up until the middle of the last decade. I've used it in the past and even have some I purchased recently for top off. I find no fault with it, in the right application. These days I use QSGB 5W-30, but my truck is burning some oil, and next time it needs a quart, it's getting QSGB 20W-50.


I hear what you are saying, sir, and in Alabama, I reckon you won't have any issues using 20W-50. I traveled through Birmingham once.

Just some notes on the topic:

1. Oil today is so much better of oil of the 80s, it is ridiculous. Oil started to improve in the 90s. The first obsolete grade was a tie between 10W-40 and 20W-50.

2. No one grade of oil, straight or with a W rating, fits every single application, but 0W-20 is by FAR the strongest candidate to do so.

3. Even Jaguar die-hard 20W-50 people use 0W-30 in their cars now. Mostly. They have seen the light.

4. Oil doesn't make engine parts "ride on a film of oil" or "cushion" an engine with thick oil. A discussion of engines is in order.

Cheers, sir

 

[ccb056]

Because Mobil 1 has a 5w50

 

[Darwin1138]

It is a product that has no relevance in today's market. Some people like to cling to the past just for nostalgic or sentimental reasons.

Before we start the flame war. I am not saying that it is a bad oil, I am sure it can protect and give adequate life to an engine, in the same way as my old VW Beetle was a good car but it clearly is in disadvantage against a modern car.

 

[MalfunctionProne]

And, remember: Contrary to popular (and incorrect) belief, a lower W number (0W, for example,) does not impact how an oil behaves hot (like 5W or 10W, for instance.) The W stands for WINTER, not weight, and has no relatiom to the second number, which is viscosity.

Advanced Motor Oil 102: The second number, in SAE (Society of Automotive Engineers) rating scale - 20, 30? 40, 50, 60, 70 - relates loosely to an HTHS range. The KV100 and KV40 numbers should be eschewed in favor of an HTHS rating.

 

[MalfunctionProne]

Originally Posted By: Darwin1138
It is a product that has no relevance in today's market. Some people like to cling to the past just for nostalgic or sentimental reasons.

Before we start the flame war. I am not saying that it is a bad oil, I am sure it can protect and give adequate life to an engine, in the same way as my old VW Beetle was a good car but it clearly is in disadvantage against a modern car.


Unless your modern car is a Harley Davidson motorcycle! I hear they do well on 20W-50 oil. I do not know why this is, though.

 

[GreeCguy]

I'm currently running a straight 40W in "Thunder the Wonder Pig," (1995 Oldsmobile Cutlass Ciera) mainly because I'm using up some old stock.

When I've finished with that, I going to use what I have left of my 20W50 in the old gal. I've got about seven gallons left from what I picked up on sale about five years ago.

I usually use it for about 4,000 to 5,000 miles and then "transfer" it to "Mighty 'D'", my 1950 Case Model "D" tractor.

 

[Red91]

If I had an older car, I'd probably run it for the heck of it. The 20W-50 of today will be like all other modern oils, in the sense that is has improved. Of course there are "better" oils available, but I can't imagine why it wouldn't work now if it worked in the 80's. I recommend 5W-30 for almost all applications if asked, but for my personal use the 20W-50 has a certain charm to it. Plus, I'm not running the 20W-50 I have as a full fill, just a top off. Quick question: if I have 5 quarts of 5W-30 and 1 quart of 20W-50, what is my final viscosity? I'm thinking it would be a 13.5W-40? I'd also use SAE 30 for top off too if I had some, and that would actually be more appropriate for top off to a pre-existing 5W-30.

 

[Olas]

20w50 is the recommended grade for my Scirocco in tropical climates. The dislike is due to the trend of thinner is better..

 

[dlundblad]

How many new cars in the US are spec'd for a 50 weight oil?

Some OM's might say its safe to use when the spec'd weight isn't available, but 9 times out of 10, that oil is readily available. My moms Elantra for example is spec'd for 5w20, but 5w30, 10w30, 10w40 and 20w50 will work if "5w20 isn't available in your country." It also shows a temperature comparison graph to show what to run in what temps.

Its not hated.. just not needed. AZ had some 20w50 last winter for $5 per jug. I should have bought some for top offs.

 

[HerrStig]

The owner's manual (which some folks consult) for my BMW airhead shows a chart in which 20W 50 is the oil of choice for about any weather I would ever ride in. So, I used it until T6 came along. I wouldn't use 0W 40 in it no matter what the trendys have to say.

 

[dlundblad]

Originally Posted By: HerrStig
The owner's manual (which some folks consult) for my BMW airhead shows a chart in which 20W 50 is the oil of choice for about any weather I would ever ride in. So, I used it until T6 came along. I wouldn't use 0W 40 in it no matter what the trendys have to say.


Are you worried about excessive shearing?

 

[Chris142]

Originally Posted By: MalfunctionProne
Originally Posted By: Darwin1138
It is a product that has no relevance in today's market. Some people like to cling to the past just for nostalgic or sentimental reasons.

Before we start the flame war. I am not saying that it is a bad oil, I am sure it can protect and give adequate life to an engine, in the same way as my old VW Beetle was a good car but it clearly is in disadvantage against a modern car.


Unless your modern car is a Harley Davidson motorcycle! I hear they do well on 20W-50 oil. I do not know why this is, though.
the rear cylinder runs very hot.its air is blocked by the front cyl and any air it gets is already heated from the front cyl.

My scout ran 360k+ on 20w50 and the guys on the scout board's liked it due to the oil pressure issues the scouts have. When I rebuilt my 392 it got 15w40.

 

[Cristobal]

Some of the forum members just flip out and think that because it is an old oil weight that it's no good.

I run it a lot, often mixed with thinner oils. But here in my area, unless you go to an altitude over 3000 feet, it is good all year long even if it is 100% of your crankcase oil.

In summer, it is good anywhere in California even at Tioga Pass.

In some countries, like Brazil or in most countries in Africa, and most countries south of Texas, it is good all year long except at the high altitudes. For instance, there is no place in Brazil where it will not work fine all year long, as Brazil has no high altitude roads.

In my car I have noticed no difference at all in warm weather mileage between a 20W-50 and a 5W-30 oil.

 

[expat]

I made the mistake of using 20w-50 exclusively in a 4 cyl Toyota PU here in Canada.
As a result the engine was showing some loss of compression when the truck rusted out at 500k miles

 

[Cristobal]

Originally Posted By: Red91
If I had an older car, I'd probably run it for the heck of it. The 20W-50 of today will be like all other modern oils, in the sense that is has improved. Of course there are "better" oils available, but I can't imagine why it wouldn't work now if it worked in the 80's. I recommend 5W-30 for almost all applications if asked, but for my personal use the 20W-50 has a certain charm to it. Plus, I'm not running the 20W-50 I have as a full fill, just a top off. Quick question: if I have 5 quarts of 5W-30 and 1 quart of 20W-50, what is my final viscosity? I'm thinking it would be a 13.5W-40? I'd also use SAE 30 for top off too if I had some, and that would actually be more appropriate for top off to a pre-existing 5W-30.


Add the quart values and divide. For instance, five quarts at 5W adds to 25. Add 20 for that one quart and you get 45.

45/6 = 7.5. For the second value, 150 + 50 = 200. 200/6 is 33.333.

You wind up with 6 quarts of a 7.5W33.33 blend, more or less.

Let me know if I did the math wrong.

 

[aquariuscsm]

I use it year round in my 300ZX (which actually specs it). I have GTX 20W50 in my car presently (need to update my sig).