Looking to buy 2012 f150 in the next couple weeks
If I lift with 35's which motor should I go with Eco or 5.0
Which would be effected by tire size in regards to fuel economy

 

EB is going to be more tolerant since it is turbocharged, but the MPG loss will be similar since the MPG loss is primarily due to increased drag. You also need to understand the change to your effective gearing - either start with 3.73s (which may be enough depending on how big you're going and what you're towing) or plan to regear to 4.10 or beyond.

 

i run the stock 3.55s with 35 inch tires. my brother is running 37s with his 3.55s. no need to regear for just a 35. just retune so the speedo and odo is correct.

 

Both motors will pull them fine. Expect a decent drop in MPG. probably low teens. Eboost will pull them better at highway speed because it has so much tq around the 1700-2000 RPM range where these trucks cruise at 70 mph

 

In went from 18mpg down to 13.5 average. On a long highway trip I can pull almost 16 average at 70-75.

 

just buy a used Raptor, they came with 35's.

 

Both motors will pull them fine. Expect a decent drop in MPG. probably low teens.