TimcoF150

2013, Screw cab, 6.5' bed, ego boost, empty. 20" wheels and abut 33" tires. 3.73 gears. 2" front lift.

Getting 10-12 city and 17ish hwy. New plugs helped. Air filter always new.

What else should I be doing? It has 64k miles, super smooth.

Other issues. Shudder and blinking engine light when I stepped on it. Soft light thump when I come to a full stop from underneath.

What else should I be changing / maintaining???

Thank you. Tim

Ricktwuhk

Blinking engine light indicates some other problem.

IAJack

I have the shortbed Screw with the 3.31 gears and Falken 33 LT's and am getting 19.2 avg.

If you have a two piece driveshaft then check your driveshaft carrier bearing and slip yoke (I think that is right) There are lots of posts on here about if if you search. I thought they fixed it on the '13's but some folks still had issues. There is a TSB about it.

Daveleeander

I have a 12 eco screw 4x4 with 3:73 rear end and 170k miles. I get about 16 overall in winter, 17.5 in summer. There are so many variables that it is almost impossible to compare MPG between drivers.
The blinking light needs coded so you can tell what it is. Could effect your MPG, could be water in CAC. Thump underneath may be two piece driveshaft as stated above.
Good luck.

D

DylanCulbreth

What they said about if you have a screw with a 6' bed like me you do have a 2 piece shaft could be the carrier bearing is worn out or out of alignment

Spiky

That sounds very normal. The highway seems right in line for those tires and gearing. The city may be low, but I'm going to assume it's partly your driving style and/or winter issues.

Engine light is a problem, worry about that.

TimcoF150

As to engine light, I read a few threads about this. The ego boost gets a shudder and blinking CEL occasionally when it's at 5k+ rpm or foot floored on gas. Several reports of this. Never stores a code, light goes away when misfire clears up. I have not tuned it nor drilled the hole in the intercooler yet.