lower mileage with Oil Change?

[Connoisseur]

I've got a 2004 Nissan Sentra SE-R Spec V. Generally I used to get about 25-26 mpg average and 29-30 mpg with all highway driving. After a recent oil change I noticed that my mpg is MUCH lower. it's now at 22mpg average with about 25mpg all highway driving. My car's got 40k miles on it, it's stick shift and I try to keep it in good condition. I also noticed the power is a bit lacking.

Has anybody had this happen after a simple oil change? Note that I didn't do it myself. I took it to a shop. as far as I know, they put in the correct weight oil.

Also, my driving style hasn't changed at all. if anything, I drive less agressively when possible.

 

[zerocool84]

Well you don't know what they put in it. You're just assuming they put the correct oil/weight/filter in it. Did they even put in the correct amount??? Have you checked your oil stick lately??? Is there any oil leakage? Did they use the correct filter?

 

[tbike06]

Check your air filter as well, that might need to be changed.

 

[Billb2]

Yes, if you had light weight synthetic oil in it and changed to a heavier weight conventional oil you could see that mileage change, but i doubt any power change would be noticeable. Are you sure it's not just the colder weather?

 

[LTC8K6]

The oil weight or change to dino oil is unlikely to make much of a mileage difference, imo.

 

[boomerang]

Check your tire pressures.

 

[thedarkwolf]

Maybe if they put gear oil in it but then you would have other problems besides mileage lol

 

[Vetterin]

Also remember that gas mileage is always down in winter with the cheap arse reformulated gas the refineries put out.