Milage increase with Platinum over T&SUV

[BTW574]

I have been runing Mobil 1 Truck and SUV since the local Walmart started carring it, with it I was averaging 15.4 MPG with my 03 Suburban that has 45000 miles on it.
I changed oil 3000 miles ago to 5w30 Pennzoil Platinum as Walmart did not have the Mobil 1 Truck and SUV so I figure I would give Pennzoil a try.
Since the oil change 3000 mile ago I have average 16MPG
All the averages are going by the MPG Average on the dash display. There has been no differance in driving style on my end. I know I am getting more MPG as I am getting more mile to a tank
Any ideas on why the increase, is the Pennzoil a better oil.

 

[theguru]

4 per cent seems a lot just from an oil change.

 

[427Z06]

I would bet the largest part of the change is due to the fact that the PENNZOIL PLATINUM 5w30 is less viscous, especially before you reach operating temps:

PENNZOIL PLATINUM 5w30
cSt@40º C 59.7
cSt@100º C 10.5

Mobil 1 Truck and SUV 5w40
cSt@40º C 102.0
cSt@100º C 14.8

 

[OldTireMan]

In May I changed my 97 Jeep GC 4.0 from Mobil 1 10w30 to Mobil 1 T & SUV. I track my mileage via an Excel spreadsheet. In 3 months the milage is down maybe .1 mpg. I also keep track of the computer mileage.
In June I changed my wifes Ford taurus from Mobil 1 10w30 to Mobil 1 Truck and SUV. It is showing about the same milage as last summer.
Not enough data to make a concrete conclusion, but I am not seeing any where near 1 or even 2 mpg decrease.

 

[haley10]

427Z06 is correct. Viscosity not necessarily quality. I am not surprized at your results at all.

 

[tenderloin]

I have been running PENNZOIL PLATINUM 5w30 for 2 OCI's in my '05 Explorer 4.0 sohc. Compared to Mobil 5w30 the engine seems quieter and smoother (I know, I know, LOL) and mpg has been at least as good, usually 1-2 mpg better. FWIW and with no used oil analysis I like the stuff. With their recent promotions it was under $2 a qt.

 

[buster]

Your going to get better MPG with any lighter viscosity. My MPG dropped slightly when going from 5w-20 to GC. That is the whole point of 5w-20 or using any lighter viscosity.