Post by justyce on Aug 4, 2017 1:21:28 GMT -5
Can someone explain to me please why people on this forum prefer to run a 10-15w40 or more ... well lets take a 10w40 and a 0w40 for example. Since 90 percent of engine wear accurs at startup, why would you use a 10w rather then the preffered 0w oil, which in the first startup of the day, flows much better, therefore less wear during startup = less allround engine wear. When it gets to operating temperatures both oils are the same.
Also something more I found written by a guy on some forum:
"Oil type... Thickness at 75 F...Thickness at 212 F
Straight 30...... 250......................10
10W-30............100......................10
0W-30..............40 ......................10
Straight 10........30....................... 6
Now you can see that the difference between the desired thickness your engine requires ( = 10 ) is closest to the 0W-30 oil at startup. It is still too thick for normal operation. But it does not have far to go before it warms up and thins to the correct viscosity. Remember that most engine wear occurs at startup when the oil is too thick to lubricate properly. It cannot flow and therefore cannot lubricate. Most of the thick oil at startup actually goes through the bypass valve back to the engine oil sump and not into your engine oil ways. This is especially true when you really step on that gas pedal. You really need more lubrication and you actually get less.
Note that a straight 10 grade oil is also too thick for your engine at startup. It has a thickness of 30. Yet at operating temperatures it is too thin having a thickness of 6. It needs to be around 10. The oil companies have added viscosity index improvers or VII to oils to solve this dilemma. They take a mineral based oil and add VI improvers so that it does not thin as much when it gets hotter. Now instead of only having a thickness of 6 when hot it has a thickness of 10, just as we need."
One thing that is no longer important is the ambient temperature. Older automotive owner manuals often recommended one oil for the summer and another for the winter. This is still necessary for air cooled engines but is no longer a consideration in pressurized water cooled engines. These engine blocks are kept at around 212 F all year round. The oil is around the same temperature as well. This allows for a single grade oil all year round. Again, this is not the same as on the track where the coolant temperature is slightly higher and the oil temperature is much higher.
People say that their old car manual says to use a 10W-40 so they would never think of using a 0W-40. Again, both are the same viscosity at normal engine operating temperature. The 0W-40 just does not thicken as much after you turn off your engine. There are now several cases when manuals for older cars have been updated to reflect this. My 550 Ferrari Maranello manual said to use 5W-40 yet the 575 manual says to use the 0W-40. The engines are the same except the 575 has more BHP. It has better acceleration and more top speed. The engines have the same tolerances."
for resource: www.ferrarichat.com/forum/faq.php?faq=haas_articles#faq_motor_oil_basics
I just wanted to start a debate because im interested in hearing more from other people..
Also something more I found written by a guy on some forum:
"Oil type... Thickness at 75 F...Thickness at 212 F
Straight 30...... 250......................10
10W-30............100......................10
0W-30..............40 ......................10
Straight 10........30....................... 6
Now you can see that the difference between the desired thickness your engine requires ( = 10 ) is closest to the 0W-30 oil at startup. It is still too thick for normal operation. But it does not have far to go before it warms up and thins to the correct viscosity. Remember that most engine wear occurs at startup when the oil is too thick to lubricate properly. It cannot flow and therefore cannot lubricate. Most of the thick oil at startup actually goes through the bypass valve back to the engine oil sump and not into your engine oil ways. This is especially true when you really step on that gas pedal. You really need more lubrication and you actually get less.
Note that a straight 10 grade oil is also too thick for your engine at startup. It has a thickness of 30. Yet at operating temperatures it is too thin having a thickness of 6. It needs to be around 10. The oil companies have added viscosity index improvers or VII to oils to solve this dilemma. They take a mineral based oil and add VI improvers so that it does not thin as much when it gets hotter. Now instead of only having a thickness of 6 when hot it has a thickness of 10, just as we need."
One thing that is no longer important is the ambient temperature. Older automotive owner manuals often recommended one oil for the summer and another for the winter. This is still necessary for air cooled engines but is no longer a consideration in pressurized water cooled engines. These engine blocks are kept at around 212 F all year round. The oil is around the same temperature as well. This allows for a single grade oil all year round. Again, this is not the same as on the track where the coolant temperature is slightly higher and the oil temperature is much higher.
People say that their old car manual says to use a 10W-40 so they would never think of using a 0W-40. Again, both are the same viscosity at normal engine operating temperature. The 0W-40 just does not thicken as much after you turn off your engine. There are now several cases when manuals for older cars have been updated to reflect this. My 550 Ferrari Maranello manual said to use 5W-40 yet the 575 manual says to use the 0W-40. The engines are the same except the 575 has more BHP. It has better acceleration and more top speed. The engines have the same tolerances."
for resource: www.ferrarichat.com/forum/faq.php?faq=haas_articles#faq_motor_oil_basics
I just wanted to start a debate because im interested in hearing more from other people..