Loss Of Mpg After First Oil Change

[jabowk]

I bought a new 2007 Prius in March and was getting mpg in the mid 50's. After the first oil change, performed at the recommended mileage by the Toyota dealership, my mpg dropped to the low 40's. What did they do? Can it be undone? Has anyone had this experience?

[hedleyf]

I bought a new 2007 Prius in March and was getting mpg in the mid 50's. After the first oil change, performed at the recommended mileage by the Toyota dealership, my mpg dropped to the low 40's. What did they do? Can it be undone? Has anyone had this experience?

:D Hi

Can only think its to do with the oil grade, Prius mpg is affected very much by oil thickness,Let us know what your climate tempertures are ie what do you think your coldest morning start would be, also what would be your highest summer temp.

[jabowk]

I live in Dallas, TX and keep the Prius in the garage so cold starts are not below freezing. Heat...well, can be nearly 100 degrees F sometimes in the summer.

I bought a new 2007 Prius in March and was getting mpg in the mid 50's. After the first oil change, performed at the recommended mileage by the Toyota dealership, my mpg dropped to the low 40's. What did they do? Can it be undone? Has anyone had this experience?

:D Hi

Can only think its to do with the oil grade, Prius mpg is affected very much by oil thickness,Let us know what your climate tempertures are ie what do you think your coldest morning start would be, also what would be your highest summer temp.

[hedleyf]

Hi,

Sorry with the delay getting back to you. a 5w/40 semi or full synthetic oil would be right ,what brand would depend on your personal choice you dont neccesssaryly need the most expensive but also not the cheapest, a good one should have on its container a fuel saving rating lable or sticker look for this,you dont need to know letters or numbers as it will be writen something like/ fuel conserving oil/ the trouble sometimes with garages is that they fit a oil that has a good mark up for them,not saying that they fit a bad oil but you could possibly have better. ask them what they fitted,We sevice a fleet of taxis here and have on ocassions put in a normal minerial oil as part of thier service without them knowing or caring only to find them return complaining of fuel consumption problems?only pass on this info as I dont drive a prius myself so make of it what you will,also consider that you maybe using the climate control more at different times,also in your winter not sure how cold that may be but the engine could run more often to keep it warm esp if using the heater or demister.Hope this helps.

Hedley,

[jabowk]

Hi Hedley

Would Amsoil be a good one to use? I have a source for it.

Thanks for the info!!!

Judy

Hi,

Sorry with the delay getting back to you. a 5w/40 semi or full synthetic oil would be right ,what brand would depend on your personal choice you dont neccesssaryly need the most expensive but also not the cheapest, a good one should have on its container a fuel saving rating lable or sticker look for this,you dont need to know letters or numbers as it will be writen something like/ fuel conserving oil/ the trouble sometimes with garages is that they fit a oil that has a good mark up for them,not saying that they fit a bad oil but you could possibly have better. ask them what they fitted,We sevice a fleet of taxis here and have on ocassions put in a normal minerial oil as part of thier service without them knowing or caring only to find them return complaining of fuel consumption problems?only pass on this info as I dont drive a prius myself so make of it what you will,also consider that you maybe using the climate control more at different times,also in your winter not sure how cold that may be but the engine could run more often to keep it warm esp if using the heater or demister.Hope this helps.

Hedley,

[hedleyf]

:D Hi;

Ya cant say Ive heard of this oil brand should be ok if it meets the specs I listed, we use Mobil 5w/30 with the fuel conserving logo on the container,