Are engines really engineered to use 5W-20?

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I think it's already been stated, possibly by me, but , the original question's answer I believe is at best "maybe" . More accurately, the 5w20 oils have been designed for the engines. In one year the oil specs for a given engine can go from 5w30 to 5w20. The engine type did not change, horsepower is the same, there is probably even some crossover point between the two model years, where the engine in the two came from the same shipment of engines, yet the oil spec is different. CAFE and oil advancement is the reason for the trend, nothing more or less. Just run what you are comfortable with. I'm one of those heavy oil experimenter as well in my '08 stang gt and my '06 4cyl ranger, they love it, and it simplifies my oil purchase, just buy the different filters.
 
So, you think GTX is 60,000cP, despite what was posted?
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Originally Posted By: oilyriser
GTX passes the 60,000 cP max limit. The actual measurement is not given.


On the SAME data sheet, a value of 40,000 cP is given for their 5w30.

These are "typical properties", whilst PYB lists 12,400 cP at the same temperature as "typical".

So, either GTX just has some horrendous low temperature attributes, or somebody has seriously FUBAR'd their data sheets.

FWIW, YB is has a lower CCS Visc as well at 5,100 at -30, where GTX's is listed as 6,600 at -30.
 
Originally Posted By: travlnman
The wife's '08 mustang gt loves the Rotella syn 5w40, for some time now. Look up the bearing clearnaces for your engine as far back as you can go, and compare it to today's. I believe you will not find much difference. The difference is first and foremost, CAFE , and second the advancement oil has made in the last 10 years. You could not pull that off 10 years ago, but oils have come a LONG way since then, with most dino Grp II and III oils , providing as good or better than most synthetics of a decade ago.


Agreed on all points. A few years ago I pulled out the clearance specs for a 1966 engine and a 2005 engine and they're hardly any different at all. Oil has changed FAR more than the mechanical parts of engines in the past 50 years. The sole exception being engines that use oil for hydraulic actuators (MDS, VVT, VTEC, timing chain tensioners, etc.) may be a little more limited in the variation they like to see. But as another poster said, if an engine can't take the difference in 30wt vs 20wt, it can't take a 15 degree change in oil temp either. Question answered, as far as I'm concerned.
 
Always used 5w30 PP in my ford box truck.Engine runs nice and silent with little oil burn.The few times I took it to ford for some work and an oil change they used 5w 20.Engine was noisy at start up and used oil at an alarming rate.
 
At 40C 5w20 is more like a 70wt....so if the engine was engineered for a 20 weight it would be oil starved until it reached that corresponding property...only then it would be protected adequately...
 
As this thread has run on and and on, I have seen very little discussion the original question, ''Are engines calling for 5W-20 any different?''.
 
Originally Posted By: nickaluch
Always used 5w30 PP in my ford box truck.Engine runs nice and silent with little oil burn.The few times I took it to ford for some work and an oil change they used 5w 20.Engine was noisy at start up and used oil at an alarming rate.


Hi nickaluch, I'm from Nassau County too.

I've been on this board a long time, and spend a lot of time reading these threads. Some guys make the change from 30 wt to 20 wt and notice more noise and more consumption, others see the opposite. I saw the opposite when I made the switch from a 30 wt to a 20 wt in my 173,000 mile Aerostar. It just seems to run better, and use less oil.

In my case I always ran dino oil in the Aerostar, and after chatting with a tech from Pennzoil I realize why the 20 wt might have helped me. He stated that the base stock their 20 grade oils comes from is more of a synthetic blend than their dino 30 grade oils are. He said that it is quite possible this is why I'm using less oil, and wasn't surprised at all, since he's heard it before. If I was using synthetic, or a blend it might have been different. I don't know, but I'm happy with the results.

I like the 20 especially in the winter time. YMMV, experiment and see what works best, then use that. There is no one size fits all, find something good and stick to it.

Engines develop a wear pattern over time, some oils might help the situation, or hurt it. Just changing brands can increase or decrease noise and oil use.
 
I had a VEGA brand new in 1972.2300 cc 1 barrel carb.Engine had a huge oil usage problem.Didn't smoke.For a long time I used QS straight 40 and such in it.Can of STP oil treatment also sometimes.Chevy replaced it a few years out at no charge.When I picked it up a person(service writer maybe)said to use 20wt.He told me that several times as I remember with me going BUT BUT WHY? I did as told with that new engine and IT never had a oil usage problem for the next two years or more that I owned that car.Not sure if this pertains to any of this but thought I'd share.
 
Shell did a study of 20 wt vs 40 wt oil. The 20 wt oil was actually thicker in the Minimum oil film thickness (micron)
under the top ring of a modern 2.0 litre gasoline engine.

Which is probably why oil use is less in some cases if its the rings that are causing the consumption. It goes against conventional thinking, but they did a study to back it up.
 
I believe demarpaint is correct saying 5W-20 grade has synthetic in it. Once you start going to thinner dino grades, there's a higher tendency for oil loss through evaporation. Synthetics have less tendency to evaporate. The thinner grades need to made with synthetic to combat the evaporation problem.
 
Originally Posted By: XS650
Originally Posted By: RISUPERCREWMAN
The timing chain tensioners on the Ford 5.4 Triton 3 valve motors are adjusted & activated by oil pressure provided by the 5W-20 viscocity along with proper function of the VTC's!!!


If they can't handle the difference in viscosity betweeen a 20 and a 30 then they can't handle a 15F change in oil temperature. What a lousy engine (assuming you are correct).


Exactly. In the dead of winter 5w20 will probably be thicker at operating temp than 5w30 at operating temp in the middle of the summer. Plus, with most 5w20s and 5w30, you're talking about a difference in viscosity of less than 2 cSt!

The whole notion that there is any component in an engine spec'd for 5w20 that will not function properly on 5w30 or 10w30 is utter nonsense.
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Originally Posted By: labman
As this thread has run on and and on, I have seen very little discussion the original question, ''Are engines calling for 5W-20 any different?''.


The only example I know of is the high volume/high pressure oil pump in the 4.6/5.4L Fords. I've only heard of this, never researched it so maybe the Ford guys can say for sure if this was done for a 20wt.
 
Originally Posted By: BuickGN
Originally Posted By: labman
As this thread has run on and and on, I have seen very little discussion the original question, ''Are engines calling for 5W-20 any different?''.


The only example I know of is the high volume/high pressure oil pump in the 4.6/5.4L Fords. I've only heard of this, never researched it so maybe the Ford guys can say for sure if this was done for a 20wt.
I actually just read an article about this oil pump in this months Hot Rod magazine I believe. It was a story about the VVT on the 4.6-5.4 and the new GM engines. They said that Ford did go to a high volume/hi pressure oil pump just for the variable valve timing. The gist of the theory was some oil volume is lost in the cam phasers and the new pump compensates for that. They did not mention however that any specific oil was required to make them work correctly. It also mentioned that the main bearings were shaped differently to go with the new pump but the clearances were the same. Very interesting...
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