Hey im new to the diesel world and dont know much about my truck yet. I have been getting what i think to be pretty poor fuel milage (11-13 in the city, 13-15 on the highway) and i dont drive it that hard. I have some mods on my truck like a bully dog triple dog, a k&n filter and cut off the muffler. After reading through this site i realized that maybe my fuel filter needs to be changed. Does anyone know if all 2005 LLYs have a fuel filter that is changable, because i think mine may not be but i am not thinking im wrong. And anyother suggestions on what to do to help my mileage? Thanks

It's safe to say ALL diesels have a changeable fuel filter. Your's is on the pass side of the engine, about center of engine, hanging over (next to) the valve cover. It's a spin on filter and should be either white or blue. Looks like a big oil filter with a sensor at the bottom. Change it every 10-15k

Thanks, and can i just unscrew it to change it, or do i have to do something else first like shut the fuel off to there, and once i change it, do i have to do anything to prime it or can i just screw the new one on?

Are you hand calculating yout MPG, or using the DIC in the dash? The tuner will throw off the DIC.

This will help you with the fuel filter.

http://www.dieselplace.com/forum/showthread.php?t=1508

thanks, and i hand calculate my mileage.

yes you have to prime the system once you replace your filter. simple to do.

I followed that link when I went to change my fuel filter, but quickly realized what a big pain in the ass it still was... It's MUCH easier to just take off the passenger side plastic shroud in the wheel well. I just used a claw hammer to take off the plastic clips, with that off the filter is very easy to get a filter wrench on and you don't need to go out and buy any tools. Just use the same size filter wrench you use on your oil filter and put it on the tapered lip of the fuel filter. To put the shroud back on I just used black wire/cable ties. Good luck.

Forgot to mention to prime the system when you replace the filter, that's the big silver button on top of the filter :)

It can be tricky to balance the filter and do it from the top. I never pre-fill mine so I don't have to worry about it being slippery or tipping it. After the first time doing it from the top, I found it simple and quick when standing on a empty 5 gallon bucket to get the right angle.

Moving to Maintenance for ongoing filter discussion. :)

Or take the passenger side battery out. That's my choice.