Thick vs thin debate...

Yep, Penrite HPR 40 25W70
You can even go thicker mate! "may also be used where 25w60 and SAE 50 are recommeded". :ROFLMAO:
HPR50005.png
 
Yep ... found it. "Your engine knows what it wants." :LOL:





My engine talks to me. last time it was demanding the following:
  • Good pour point,ccs and mrv
  • Very low Noack
  • Good HTHS
  • Low vii
  • high flash point
  • Viscosity grade > 20
  • A3/B4
  • Lower spread
  • Good chunk of Moly
  • MB, VW, Porsche and BMW approvals
  • ...
some of the demands overlap but I said sorry, can't find one under $6/qt. When and if I do, I'll buy it. Meanwhile you are getting the bitog flavor of the month ...
Engine said :cry:
 
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Post of the month winner thus far.


I will say that certain oils have run quieter in my car than others. Why? I don't know. I do think even the louder ones were working as they should. No doubt.

I do like quieter running if I have my way.
 
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Post of the month winner thus far.


I will say that certain oils have run quieter in my car than others. Why? I don't know. I do think even the louder ones were working as they should. No doubt.

I do like quieter running if I have my way.
Were heavier oils the quieter ones?
 
Yes, beating a dead horse here. I’m not looking for an argument but am curious. It is often cited here that engines can handle running a wide viscosity range of oils, which I agree with. But for some reason 0w20 (or thin oils in general) are viewed as the devil and shouldn’t be used in engines that previously specified a higher viscosity.

Example: the VW / Audi 1.4 TSI and 2.0 TSI. They previously ran 502.00 (30-40 grade) but now run 508.00 (0w20). So again, if engines can handle operating under such a large viscosity range (think thick oil when cold and thin when hot, which is quite the spread in CST measurement, and they DO handle that viscosity difference well)...why would it be detrimental to that engine to drop the grade down to a 20 from a 30? That is only a few CST thinner at operating temp (12 cst for 30 and 7ish cst for 20). That seems negligible IMO

Honest question.
It's not a problem as long as the engine from an engineering perspective can handle it. People erroneously assume manufacturers purposely choose lighter weight oils in order to sacrifice engine life for fuel efficiency. There's zero proof of that. Yes some engines may have been initially designed/tested on a 30w/40s but at the time were never tested on a 20w due to a lack of a standard or financial incentive to develop one.

The reality is that almost every major engine failure is due to either poor material choices or poor design rather than the choice of oil weight.
 
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It's not a problem as long as the engine from an engineering perspective can handle it. People erroneously assume manufacturers purposely choose lighter weight oils in order to sacrifice engine life for fuel efficiency. There's zero proof of that. Yes some engines may have been initially designed/tested on a 30w/40s but at the time were never tested on a 20w due to a lack of a standard or financial incentive to develop one.

The reality is that almost every major engine failure is due to either poor material choices or poor design rather than the choice of oil weight.
Actually there is only proof that they select thinner oils for fuel economy.

No engine will be damaged by a thicker oil. Some engines can be specifically designed for thinner oils, or tolerate them. No one can refute that a higher HT/HS with a corresponding higher MOFT isn't more margin to prevent metal-to-metal contact.
 
Temps inside the engine could be 400F+ in some parts and 230F+/- avg oil temps ... I wouldn't worry too much about ambient temp.

I have 2 cars that OM recommends 5W20 and 0W20 in US. One is a truck with over 10K towing capacity. The manufacturers don't think ambient temps in US will be an issue and neither do I except i prefer a thicker oil in general and especially if I'm towing.
*I mention ambient temps as the Hyundai owners manual mentions using 5W30 over 5W20 in summer time temps .
 
*I mention ambient temps as the Hyundai owners manual mentions using 5W30 over 5W20 in summer time temps .
Yes, some owner's manuals list a specific temp range especially older manuals and some newer ones show xW20 is good for all temp ranges but also allow higher viscosity over certain ambient temp and/or operating conditions.
I have all of those owner's manuals. The idea is that in general, the hotter the engine, the higher the viscosity. Engine heat can come from high speed/rpm, towing, load, higher ambient temp, etc. However ambient temp impact is not as significant as others.
 
Yes, some owner's manuals list a specific temp range especially older manuals and some newer ones show xW20 is good for all temp ranges but also allow higher viscosity over certain ambient temp and/or operating conditions.
I have all of those owner's manuals. The idea is that in general, the hotter the engine, the higher the viscosity. Engine heat can come from high speed/rpm, towing, load, higher ambient temp, etc. However ambient temp impact is not as significant as others.
It is when you turn the A/C on ;)
 
It is when you turn the A/C on ;)
That's right. No A/C during summer it adds more load to engine. Roll down the windows and turn the heater on :)

there used to be signs on some freeways (going uphill) to turn the AC off. Not sure if we still have them or not. also in old days small 4-cyl cars didn't come with "factory air".
 
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