Are engines really engineered to use 5W-20?

[ekpolk]

Originally Posted By: OVERK1LL
. . .


My point is that the "evil" 5w40 is actually THINNER at colder temperatures than the aforementioned 5w20. [/quote]

Your observations are true enough. OTOH, these temp extremes are only seen in the engine for a brief, transient period until the engine warms up. No oil on the planet (yet anyway) is going to be able to offer the absolute (watery) viscosities we see in typical 20-40 wt oils, when they're cold. Every engine out there has to be designed to survive the warm-up period. That doesn't necessarily mean that the very thick viscosities the engine sees during warm-up are good for the engine.

 

[OVERKILL]

Originally Posted By: ekpolk

Your observations are true enough. OTOH, these temp extremes are only seen in the engine for a brief, transient period until the engine warms up. No oil on the planet (yet anyway) is going to be able to offer the absolute (watery) viscosities we see in typical 20-40 wt oils, when they're cold. Every engine out there has to be designed to survive the warm-up period. That doesn't necessarily mean that the very thick viscosities the engine sees during warm-up are good for the engine.

True. But in terms of Ford, 5w40 is a specified grade BY FORD for the Modular engines (in Australia). Which is part of the reason I was so readily prepared to run it. And have been impressed with the results.

My point was simply that a "heavier" oil is not always heavier, and that 5w20 is a far cry from its hot viscosity during warm up, especially in cold climates. If these parts were that sensitive, they would be failing just by virtue of ambient temperature discrepancies in North America; the 3V would never live in Winnipeg

 

[72customdeluxe]

Going back to "are engines designed for 5w-20 oil"I thought i'd throw in that my 1972 chevy owners manual states (on the oil viscosity by temp. chart with arrows, y'all know what i'm talking about) that you should use 5w-20, or 5w-30 if 20 isn't available for temps at or below 20 degrees fahrenheit. I don't think clearances have anything to do withwhat oil is recommended

 

[Durango]

Originally Posted By: Dave Sherman
Somebody on another forum is trying to convince me that my engine might have oil starvation issues because I'm running 5W-30 in it, even though it says 5W-20 on the filler cap, since "the passages are smaller and the clearances are tighter". Specifically, it's a Honda K24Z1. I find that hard to believe, but I don't know if this was an engine that previously called for 5W-30.


Dave Sherman,

My buddy told me he heard that if the oils too light the lube can get squeezed our from between parts causing premature parts failure. That was long time ago when everyone thought 20W-50 was considered OK to use in most engines. He didn't know then that the average/common oil used was 10W-30 and not 20 weight oils.

Today engines/oil is a whole NEW ball of wax compared to 30's years ago.If you want to save a few bucks in gasoline then you have no choice but to go lean reasonable for the economy.

In my 01' Durango V-8 the specified oil weight is 5W-30 but I see no real reason WHY I can't go to a 20 weight as the newer Chrysler/Dodge truck allow.

Personally I'd say it's MORE than fine to try the 20W weight. It's not much different from the common 30W weights.

Durango

 

[BuickGN]

Originally Posted By: Durango

Today engines/oil is a whole NEW ball of wax compared to 30's years ago.If you want to save a few bucks in gasoline then you have no choice but to go lean reasonable for the economy.

In my 01' Durango V-8 the specified oil weight is 5W-30 but I see no real reason WHY I can't go to a 20 weight as the newer Chrysler/Dodge truck allow.



HTHS, oil pressure.

 

[Bryanccfshr]

we have a few Magnum v8 Durango's in our fleet (most are being retired and surplussed. They have been running fine for a few years on 5w20 since the oil ordered for the bulk tanks is aimed at the fords. I see no reason not to expiriment within the energy conserving range

 

[BuickGN]

Originally Posted By: Bryanccfshr
we have a few Magnum v8 Durango's in our fleet (most are being retired and surplussed. They have been running fine for a few years on 5w20 since the oil ordered for the bulk tanks is aimed at the fords. I see no reason not to expiriment within the energy conserving range


I would have no problem experimenting on an old truck that you didn't really care about. It's just that the downside of too thin of an oil is likely worse than too thick of an oil.

I guess I'll remain the resident heavy oil experimenter with my TL and it's soon to be 40wt oil.

 

[OVERKILL]

Originally Posted By: BuickGN
Originally Posted By: Bryanccfshr
we have a few Magnum v8 Durango's in our fleet (most are being retired and surplussed. They have been running fine for a few years on 5w20 since the oil ordered for the bulk tanks is aimed at the fords. I see no reason not to expiriment within the energy conserving range


I would have no problem experimenting on an old truck that you didn't really care about. It's just that the downside of too thin of an oil is likely worse than too thick of an oil.

I guess I'll remain the resident heavy oil experimenter with my TL and it's soon to be 40wt oil.

Hey, don't leave me out! I've converted everything I own over to TDT 5w40

 

[Audi Junkie]

Originally Posted By: OVERK1LL

Riddle me this: When its -35C out, what visc are the VCT's seeing with Castrol 5w20 in the pan? I'll give you a clue: higher than Delvac 1 5w40......

The cP of Castrol GTX 5w20 is 60,000 at -35
the cP of M1 TDT 5w40 is 25,400 at -35

Hmmmmmmmmm............



Let me stop you right there.

Your conclusion is wrong. The data is not accurate. Often PDS lists the minimum numbers for the API spec as the spec of the oil, in this case GTX is way off. A number rounded off to the 10,000 for every visc on the list makes me think so.

http://www.castrol.com/liveassets/bp_int...psd_gtx_usa.pdf

Even if you don't think so, common sense says it is thinner than 5w-40. I don't know why you choose GTX as an example, but I assure if you look at other 5w-20, you will find more accurate info. Are you using MRV numbers? ASTM D-4684? Mobil does not even list a test protocol for CC numbers.

http://www.mobil.com/USA-English/Lubes/PDS/GLXXENPVLMOMobil1_Turbo_Diesel_Truck_5W-40.asp

My calculations put M1 TSUV (100.4/14.9cP) at 32292.63cP and GTX (56.1/9.1cP) is 19034.08cP at -35c.

http://www.widman.biz/Seleccion/Viscosidad/Conversiones/Graph/graph.html

I do understand your point of different oils presenting the same visc to the engine at different temps, but your example is WAY off.

 

[beanoil]

Originally Posted By: SAJEFFC
I agree but I think a lot of people over anaylize that fact. I'm 1500 miles into a run of M1 0W40 in my 08 4.6 3V and have noticed NO differences at all in mileage, power, or engine noise. Frankly I'm a little amazed because I was at least expecting it to be a little doggier or something! Who knows...there probably is way more leeway on viscosity on these new engines than we think. Just my .02

Agree. I'm currently 1000 miles into a 5 quart fill of straight 40 weight in a Chrysler that has 5w20 printed on the fill cap. No change in starting, mileage, or running. During the summer heat, I have no reservations running heavier oils. This is a bit "out there", I'll admit, but those 5 quarts have been setting a while, and I'll be through the 5k OCI in about 6 weeks, before cold sets in. Gotta love those 1.00 WM filters, and .33 oil from AA.

 

[OVERKILL]

Originally Posted By: Audi Junkie
Originally Posted By: OVERK1LL

Riddle me this: When its -35C out, what visc are the VCT's seeing with Castrol 5w20 in the pan? I'll give you a clue: higher than Delvac 1 5w40......

The cP of Castrol GTX 5w20 is 60,000 at -35
the cP of M1 TDT 5w40 is 25,400 at -35

Hmmmmmmmmm............



Let me stop you right there.

Your conclusion is wrong. The data is not accurate. Often PDS lists the minimum numbers for the API spec as the spec of the oil, in this case GTX is way off. Even if you don't think so, common sense says it is thinner than 5w-40. I don't know why you choose GTX as an example, but I assure if you look at other 5w-20, you will find more accurate info. Are you using MRV numbers? ASTM D-4684? Mobil does not even list a test protocol for CC numbers. My calculations put M1 TSUV at 30000cP and GTX is 20000cP at -35c.

I do understand you point of different oils presenting the same visc to the engine at different temps, but your example is WAY off.


I chose GTX because it had a readily available data sheet.

I have the PDF saved here.

It states:
Low Temperature Pumping Viscosity (cP max):
ASTM-4684: 5w20: 60,000 @ -35C

For Mobil 1 TDT:
http://www.mobil.com/USA-English/Lubes/PDS/GLXXENPVLMOMobil1_Turbo_Diesel_Truck_5W-40.asp

It lists MRV as 25,400 at -35C

MRV = ASTM D 4684

Quote:
Engine oils are formulated with pour point depressants (PPDs) to counteract the formation of wax crystal networks at low temperatures. These relatively fragile structures are strong enough to impede oil flow and can be easily characterized by standard ASTM low shear rate, low-temperature rheological methods such as:

-Mini Rotary Viscometer (MRV ASTM D 4684)
-Brookfield (ASTM D 2983)
-Scanning Brookfield (ASTM D 5133)
-Pour Point (ASTM D 97, D 5950, D 5985)

 

[Audi Junkie]

I know where you got the numbers, I'm saying your conclusion is wrong, based on bad data, apparently.

 

[OVERKILL]

Originally Posted By: Audi Junkie
I know where you got the numbers, I'm saying your conclusion is wrong, based on bad data, apparently.


It is just the data presented. If Castrol presents it as being 60,000 why would I conclude that it is 40,000 higher than that? Why would they intentionally FUBAR it? I can see them rounding it.... But not by 40,000

My conclusion makes sense based on the data given and provided we use -35 as the point of comparison. As we get warmer, obviously the 5w20 is going to be thinner. But at what point, I don't know off-hand.


EDIT: Just to add, PP shows MUCH better values than GTX here, as per your request to look at other 5w20's, which I have. I have a lot of the data sheets saved here for quick reference. But of course, as we can see, if the data provided by the manufacturers is any indication, that not all 5w20's are created equal.

 

[aquariuscsm]

Originally Posted By: BuickGN

I guess I'll remain the resident heavy oil experimenter with my TL and it's soon to be 40wt oil.

^^Right on my brutha!

 

[Audi Junkie]

Originally Posted By: OVERK1LL


My conclusion makes sense based on the data given and provided we use -35 as the point of comparison.


No, it's still wrong. 5w-20 is thinner than 5w-40 by definition. That's what "makes sense".


Pennzoil 5w-20 Dino

MRV Viscosity, cP (°C) ASTM D-4684 12,400 (-35)

 

[pzev]

Guy came in to an auto parts store I worked at, was looking to try some new oil. He said people have been talking about these new thinner oils, and that he thinks they would work good in his truck.
I found this odd, as he was reading the label on the back of 20w-50 Valvoline VR1 "Racing" oil. I asked him what he was running in it now, and he said the VR1 straight 50 weight. He said his truck has always been run on straight 50. It was a mid 90's chevy pickup with a 350...it had 360,000 miles on the original engine. He said he used nothing but Fram filters....
I told him to stick with what works, as 360k miles is pretty darn good in a gas engine. He bought 6 quarts of the VR1 50w.

If I recall, Chevy specs 5w-30 for that engine and year. Now I know a 350 chevy isn't exactly a modern I4, but this should provide some evidence that engines can run on a wide variety of viscosities with little trouble....assuming your weather permits such oil.

 

[oilyriser]

Originally Posted By: OVERK1LL

It states:
Low Temperature Pumping Viscosity (cP max):
ASTM-4684: 5w20: 60,000 @ -35C




"max"

 

[CharBaby]

Re: Are engines really engineered to use 5W-20?

I think that the 5W20 motor was formulated to be used in engines because the MFG's required it.

 

[Epic_]

Originally Posted By: pzev
My car is easy on oil anyways, it wouldn't be exciting enough for the bitog crowd. Lets find someone with a Toyota 1mz and get them to do it.


*Cough*

 

[OVERKILL]

Originally Posted By: Audi Junkie
Originally Posted By: OVERK1LL


My conclusion makes sense based on the data given and provided we use -35 as the point of comparison.


No, it's still wrong. 5w-20 is thinner than 5w-40 by definition. That's what "makes sense".


Pennzoil 5w-20 Dino

MRV Viscosity, cP (°C) ASTM D-4684 12,400 (-35)


Makes sense to you maybe. I have no problem wrapping my head around a synthetic HDEO flowing better at -35C than a conventional oil.

As you know, the pour point of synthetics (take GC for example) are substantially lower than conventional oils. You could take a synth 5w40 and put it out in -40 weather in Winnipeg and it will flow quicker out of the bottle than a conventional 5w30.

Now take that same logic and apply it to this situation.

I am comparing a conventional 5w20 (GTX) to a synthetic HDEO. Whether it "makes sense" to you or not, at a temperature extreme of -35C, ACCORDING TO THE DATA PROVIDED BY THE MANUFACTURERS, Mobil 1 TDT (synthetic) is THINNER than Castrol GTX (conventional) 5w20.

Pennzoil YB 5w20 obviously has superior low temperature performance over GTX if we again, use the manufacturer provided numbers for reference.