I never posted on here much, but I'm in need of a little help or guidance. Over the last year or so my mileage is dropping drastically (my calculation, not the dash) and I am averaging about 12.5 MPG and majority of my driving is highway. For the most part I was constantly averaging 16MPG with a leveling kit and 33's. Last night I decided to change the plugs, wires and air filter and I took the intake tube and throttle body off just to clean up stuff while I was in there and found a ton of oil and what looks to be coolant. I personally have never seen this much oil inside an intake manifold, normally it is just a light film. I have been going back and fourth for a few months with getting a new truck or just keep making repairs to this one since its been paid off for a few years. I know this is not something that can be solved over pictures on the internet, but does this look to be possibly something that is pointing to a larger problem. I checked the dipstick and oil cap and I did not see anything unusual. Plugs also did not look to be anything abnormal either when I removed them. The truck is a 2014 with 142K on it. Thanks in advance for any help.