kingbriani

When my car went over 10,000 miles I switched to amsoil synthetic engine oil and have since noticed a 2-4 mpg increase in fuel efficiency. I did some calculations and using the conservative figures of going from 23 mpg before to 25 mpg after, I found that I'm saving over 17 gallons of fuel over the 5000 mile life of the oil. Figuring that gas is around $4.40/gal, that equates to a $74.80 savings, more than making up for the increased cost of the oil. Since the figures I used were conservative, I'm probably saving much more than that. Just thought I'd pass this finding along since saving money at the pump is a big deal lately.

addisonc

You are assuming that only amsoil synthetic oil can give you this gain. What about cheaper alternatives like Mobile one?

kingbriani

I'm not assuming anything, only reporting findings based on my experience. I have no experience with mobil1 so couldn't comment on how it might affect gas mileage.

EVAN&MONICA

thanks kingbraini Ive been considering switching over for some while but I think youve convinced me with this one

JackS

No argument from me since you may be right. The problem is there are always the variables i.e- type of driving, weather, road conditions, break-in and indeed a subconcious desire to improve on your previously recorded mileage whch may have (ever so slightly) changed the way you drive. The good news is that whatever is causing your mileage to increase is a plus.

G

You did not state how many tanks you were comparing. If you are comparing 1 to 1, you are not doing it correctly. The best way is to average out for 1000+ miles of similar driving.

I would be interested to hear if anyone else has experianced and recorded this with their S, or other car.

shotiable

theres usually a boost in mpg's when you change oil then the mpgs dip down as the oil gets dirty.

G

That is interesting.

When I had my TSX I had a unique experiance. Some background info, I had a spreadsheet that held all info and calculated mpg, cost, etc. I noticed that I would have reduced mpg for the first 1-2 tanks after an oil change. After that it would level out and remain relatively constant. This was the case for every change. I thought it was interesting when I discovered it after 4or 5 oil changes.

kingbriani

This trend has held true for each tank since my oil change 4-5 tanks ago. I'm not basing this on one tank. Before the change, I would typically average between 22-24mpg as calculated after each fill up. Immediately after the change and continuing on until now I have been getting 24-26 mpg as calculated at each fill up. Have not had a tank average below 24 mpg since the fill up. This is comparing my daily drive to and from work and any errands I may do so the conditions are very similar between tanks. When I changed my oil with regular dino oil when my car had 5000 miles, I did not experience this jump im mpg.

SheDrivesIt

What time of year? Might have been the change over to summer fuel. I have no idea how much you drive so 4 or 5 tanks ago could be a couple of weeks or it could be months ago.