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I live in Riverside and it will get up to and maintain over 100 degrees+ soon, most of the driving is local. I have a 2001 Trans Am currently with Mobil 1 5W30.
Should I change the viscosity for summer?
Does anyone change their viscosity during the summer months, I live where it is normally 110 for long periods.
Same here and I have vehicles that call for 0w20. I don’t think it matters too much really. That being said this last change I put 0w40 in one of them for the first time and once again I don’t think it makes much of a difference. It might be a little quieter with the 0w40 though.
Last edited by Y2K_Frenzy; 05-01-2024 at 07:01 AM.
M1 euro 0-40 is an excellent oil.......I use it exclusively in my car.....cheap at wally world in jugs OR the box....cant beat it for the price....and is a highly rated oil
Leave it alone for summer. Your car has an oil cooler. If the cooling system (radiator, fans) is doing its job, the oil temp won’t climb very much anyway.
Not all oils within the viscosity range weigh the same. The “weights” fall with a range and some will be thicker than others. Some 40 weight oils are just barely thicker than some of the “heavier” 30 weights and so on and so forth.
I’m changing the oil in my wife’s vehicle tomorrow and it calls for 6 quarts of 0w20. I bought a 5qt jug of Castrol Edge 0w20 high mileage and 1qt of the same but in a 5w30. It is going in a low mileage vehicle.
This particular 0w20 has a cSt (“thickness”)of 8.8 @ 100*C and the 5w30 is 11.3. My 5qt to 1qt mix comes out to have a cSt of 9.1 @ 100*C. So it’s still with in 20 weight oil specs but it’s now on the high end of the scale. There are online calcs to do the math.
FWIW Mobil1 5w30 has a cSt of 11.1 @ 100*C.
*Sidebar*
My wife’s vehicles oil filter is a friggin cartridge filter. The Fram line was all that was on hand so I opened the boxes and compared each tier. The cheapest and the middle priced had the same paper feeling filer media except the middle level which is the XG or “extra guard” had less space between the pleats and it felt tighter when you squeezed it. They say the Extra guard is rated for 15k miles. The top tier which I think it’s called the “Synthetic Ultraguard” or something like that has a different filter media. It’s probably paper too but it feels more like a T-shirt than a manila accordion folder and they advertise it as being good for 20k miles. I think it was also harder to compress than the lowest tier. The cheapest one felt like an accordion folder with only a few papers in it and the more expensive one felt like it had a few years of files no one will see again. Young dudes are like what’s an accordion folder? An instrument?? The one that is on there now is the middle of the road Fram that they advertise good for 15k miles. It and the oil have a little over 3k miles on them now. I opted for the Ultraguard this time, I didn’t think to open the boxes at the store the last time. But I bet any filter will suffice these days, especially for me since I change between 3k to 4k mile intervals still.
Image credit to some dude on bobistheoilguy.com
Last edited by Y2K_Frenzy; 05-11-2024 at 10:37 PM.
Not all oils within the viscosity range weigh the same. The “weights” fall with a range and some will be thicker than others. Some 40 weight oils are just barely thicker than some of the “heavier” 30 weights and so on and so forth.
I’m changing the oil in my wife’s vehicle tomorrow and it calls for 6 quarts of 0w20. I bought a 5qt jug of Castrol Edge 0w20 high mileage and 1qt of the same but in a 5w30. It is going in a low mileage vehicle.
This particular 0w20 has a cSt (“thickness”)of 8.8 @ 100*C and the 5w30 is 11.3. My 5qt to 1qt mix comes out to have a cSt of 9.1 @ 100*C. So it’s still with in 20 weight oil specs but it’s now on the high end of the scale. There are online calcs to do the math.
FWIW Mobil1 5w30 has a cSt of 11.1 @ 100*C.
*Sidebar*
My wife’s vehicles oil filter is a friggin cartridge filter. The Fram line was all that was on hand so I opened the boxes and compared each tier. The cheapest and the middle priced had the same paper feeling filer media except the middle level which is the XG or “extra guard” had less space between the pleats and it felt tighter when you squeezed it. They say the Extra guard is rated for 15k miles. The top tier which I think it’s called the “Synthetic Ultraguard” or something like that has a different filter media. It’s probably paper too but it feels more like a T-shirt than a manila accordion folder and they advertise it as being good for 20k miles. I think it was also harder to compress than the lowest tier. The cheapest one felt like an accordion folder with only a few papers in it and the more expensive one felt like it had a few years of files no one will see again. Young dudes are like what’s an accordion folder? An instrument?? The one that is on there now is the middle of the road Fram that they advertise good for 15k miles. It and the oil have a little over 3k miles on them now. I opted for the Ultraguard this time, I didn’t think to open the boxes at the store the last time. But I bet any filter will suffice these days, especially for me since I change between 3k to 4k mile intervals still.
Image credit to some dude on bobistheoilguy.com
Here is an example comparing two different brands of 0w20. While both are 0w20’s the Castrol is marginally thicker than the Valvoline.
04-28-2024, 04:34 PM
Summer Temperatures Oil viscosity 
