Summertime = Thicker Oil ?

[tanker4lyfe]

Just wondering if any of you guys do this as the weather heats up. seems youd want thicker oil when temps get in the 90-100deg. Currently running Mobil1 5w-30 and AC Delco filter and thought maybe of switching to 10w-30. Just had to ask you guys first.

[dlstewart01]

5W30 and 10W30 are both 30 weight at operating temperature. The 5W30 will flow just slightly better at start up when cold.

[Wingnut]

I run exactly what the manual tells me to.

[Black02Silverado]

Like snakedoctor said, they are both the same weight when your engine is up at operating temp.

[dlstewart01]

Actually looking at Mobil 1 product data sheet The 5W30 is just slightly thicker than 10W30 at operating temps..

 

5W30 Viscosity @ 100ºC, cSt (ASTM D445) 11.0

 

10W30 Viscosity @ 100ºC, cSt (ASTM D445) 10.1

The higher the number the thicker the oil.

 

Viscosity charts with ranges for each weight..

 

http://www.bobistheoilguy.com/viscosity-charts/

[desrtrat]

i have been using M-1 5w-30 for years here. summer time temps can hit over 120* for weeks at a time, and i have had no issues at all..

[tanker4lyfe]

Ok thanks guys figured so but had to ask.

[cbxeric]

It matters more for extreme cold weather starting, 5w-30 flows better when cold than 10w-30.

[Z45]

It matters more for extreme cold weather starting, 5w-30 flows better when cold than 10w-30.

Also when starting your engine from cold state which is everyday for most, 10W-30 will use more fuel over the long run.

 

 

Note- Ford and many import brands are requiring 5W-20 or 0W-20 and some mandate only synthetic like Toyota.

[DwayneJ]

That has much more to do with CAFE than it does cold starts. If you actually did research you would find the same exact engines shipped elsewhere get thicker oil recommendations.

[05GMCZ71]

Actually many of the imports need Synthetic because they have such small valve passages. Talk about poor designing!

[CapitalTruck]

Mobil 1 5w30 will cover you no matter what. You won't have a problem with that and an ACDelco filter. I've done a lot of towing in the Texas heat with the little 4.8, never a problem. 900 pounds shy of my gross combo weight rating.

[DwayneJ]

walmart brand non-synthetic will do the trick too.

 

Engine failures are a VERY VERY rare thing these days, particularly those caused by lubrication issues.

 

The "I use such and such and it works great because I never had a problem" reviews are a big joke at best.

 

I wish folks would either spring for Used Oil Analysis or at least go to the site snakedoctor linked and look at results from people who share them.

[CapitalTruck]

I used to get my oil analyzed all the time. Blackstone labs always gave me favorable reports about my Mobil 1 5w30. Additionally, I have always used the oil life system to time my oil changes. Blackstone has indicated that with Mobil 1 there was always plenty of additive left and no abnormal amount of metal which would indicate engine wear. All of this was with Mobil 1 5w30 and a ACDelco filter, be it towing a huge boat across the country in the summer time or driving here in town. You mention Wal-Mart oil. I think ExxonMobil makes their regular oil, which is fine if you use regular oil. However, their synthetic oil is made by Warren Oil Company. The numbers on their synthetic are worse than some of the better dino oils out there. Also, I'm not necessarily worried about lubrication failure, I'm more concerned with long term accumulated wear and preventing it as much as possible. I'm going for at least 250k on this truck.