Sudden Drop in Fuel Economy After Service - Ethanol additive in fuel?????

[snowbird]

All the gas stations near me are adding ethanol now. Does the type of gas make a difference? BP is pushing their "invigorate" but I notice its not a "Top Tier" company. Others swear by Mobile. any opinions?

[Enorris]

Same thing here with the Tire Pressure. I got my Prius serviced and left for a long trip. I noticed that the ride was a little softer. I then realized what had happened. My mileage had also dropped the 3mpg.

[pointreyesman]

The HydroEdge tires from Michelin were loud enough to resemble the sound of snow tires. Now that they have been replaced with other tires, the noise level has dropped and the mileage has gone up somewhat near to normal for my driving: 44-46 average per tank of gas.

[oldualer]

I am interested in tire pressures. My 2008 came with 37# in the tires. Can you safely run 42# & how much would that affect mpg? This winter my mileage has gone from 45-46 to 33-35. The cold weather has probably lowered the pressures but not enough for the warning light to illuminate. Does it ride ok with 42#? Thanks a lot. I got my car last April & love it. It's surprisingly good in snow.

[JimboK]

Originally Posted by oldualer

I am interested in tire pressures. My 2008 came with 37# in the tires. Can you safely run 42# & how much would that affect mpg? This winter my mileage has gone from 45-46 to 33-35. The cold weather has probably lowered the pressures but not enough for the warning light to illuminate. Does it ride ok with 42#? Thanks a lot. I got my car last April & love it. It's surprisingly good in snow.

You have two questions I'll answer: Is 42 safe? and, How does it ride?

It is quite safe, and it could be argued, safer than 37. 37 isn't by itself unsafe, of course. But 42 gives you a little more margin of error for reductions in pressures from things like slow leaks or ... cold weather. Which makes a great opportunity to emphasize the importance of regular tire pressure checks, especially as the weather cools. Anyway, many in these parts run 44 in the front (the max cold inflation pressure for the Goodyear Integrity) and 42 in the rear. (The 2# offset is to adjust for the heavier load in the front end.) Though not recommended, some even run them higher, being very confident in a substantial margin of safety on the high side.

As for ride, you might notice it to be a wee bit harder.

So it's a personal choice: better fuel economy or possibly a slightly better ride.