The 1947 - Present Chevrolet & GMC Truck Message Board Network - View Single Post

*HEI451* · 10-17-2011, 10:00 PM

Check the oil level in the engine. If it magically made the oil level rise all by itself, there is probably fuel in the oil from a leak in the fuel pump diaphragm.

Also, the fuels are now more oxygenated than before, with the percentage of ethanol up from 10 to 15 percent. We have seen an overall mileage loss of between 1 to 3 mpg with the new formulation.

10-17-2011, 10:00 PM	#5
HEI451 Account Suspended Join Date: Mar 2011 Location: Yerington, Nevada Posts: 864	Re: Really bad milage Check the oil level in the engine. If it magically made the oil level rise all by itself, there is probably fuel in the oil from a leak in the fuel pump diaphragm. Also, the fuels are now more oxygenated than before, with the percentage of ethanol up from 10 to 15 percent. We have seen an overall mileage loss of between 1 to 3 mpg with the new formulation.