Just recently added a CAI and exhaust to my 99 4.6L. Wanted some advise on what i should invest in next to improve mileage and performance.

Headers, programmer, high flow cats?

 

I couldn't see headers, prog. and cats hurting mileage, but a light foot is no. 1. Be very vigilant about monitoring tire pressure, It can make a difference over time. But don't expect miracles out of mods, it's still a truck and it will suck tanks dry !

 

Trying to keep the foot off the gas is a lot harder when you got some serious sound coming out the tail pipes. Maybe that was a bad decision. lol

 

Just out of curiosity how many miles are you guys getting on a full tank of gas. With my 5.4L I get about 220-250 miles depending on where im driving. But the other day my dad was like yea I get about 280-300 miles around town. He has a 4.6L. Does it really make that much of a difference?

 

the biggest thing you can do to a 4.6 is get rid of the stock radiator fan, and put in 2 16" electric fans witha thermostat gain 2mpg, the next thing dual exhaust 1.3 mpg gain with cool sound next get a scan gauge 2 to moniter your instant mpg.

i get 320-340 miles per tank got 370 once going with a a good tail wind with my 99 4.6

 

just filled up last night actually and had about 305 miles on the tank with maybe an 8th of a tank tops left in it. already had the exhaust redone twice. midas put on the first new piping and it looked like a 16 year old did it in his own garage. took it down to carx and watched the guy install it and finally got what i wanted. props go out to carx.

 

Have you purchased those yourself? if so where and which ones did you buy? website? thanks

 

I get about 300 miles to a tank with 41" tires sounds like there is some lead foots around. i got aroud 340 with 37" tires and my speedo is calibarated right berfore someone asks. so i get on average now 13.5 mpgs with the 41"s with 3.73 gears. i plan on swaping out gears for 4.56s and electic fan kit very soon so should be back to around 15 mpg i hope