10w-30 oil = decrease gas mileage?

[mickey513]

I recently had a oil change and used 10w-30 instead of 5w-30 motor oil. I notice a decrease in gas mileage. Anyone else have the same problem???

[autxr]

There should be no significant difference in mailage. After about 5 minutes the oils are virtually identical.

Anyhow, the diffrerence is likely to be found in the right foot, or the weather. A 5 or 10 degree temperature drop could make a noticable difference.

Scott

[mickey513]

The weather around my place has been cold and raining, so my heat and ac is on more then usual but I got 30miles LESS this time then the last time I filled up. Which caught me by suprise, and thinking back, the only thing different I did was get the oil change and 10w-30 was used instead of 5w-30. But Thanks for the info.

[VZV21]

It's probably from using the AC alot and/or defoggers (which are linked to the AC compressor)

[cruzerz545]

Did use use synthetic? 10w30 regular will decrease milege and power.

Originally posted by mickey513
I recently had a oil change and used 10w-30 instead of 5w-30 motor oil. I notice a decrease in gas mileage. Anyone else have the same problem???