I'd put a set of 35/12.50/R16 on it for highway, down side it kills your city mpg a little. I have 35/12.50/16.5 on my truck and at 2000rpm I'm running about 72mph. If you do change tire size you need to go to the dealer and have them change your shift points and reset you speedo.
Poor mpg
- Thread starter RON.B54
- Start date
Thank you guys for all your help,I really appreciate it.I will try what all of you have suggested. I do need to ask , anyone got a good used tailgate for sale then. My truck had that flow through on it when i bought it.
OK.. here's my suggestions..
*your 285's create more drag and threw your speedo off about 4mph. Sure the problem doesnt lie there? Find a set of 235/85R16's and use them instead.
*intake- throw that K&N squirrel trap in the trash, do the DIY Tymar intake.
*exhaust- low restriction muffler is a must.. chrome plated fully illuminated genuine accessory exhaust systems are not; Flowmaster or a Dyno Max will suffice. (the biggest exhaust restriction on a SD is the turbocharger anyway)
*aerodynamics- solid tailgate
*aerodynamics- get a hunk of old conveyor belting and make an air dam & skirts that hang down at least as far as the axles do. The front bumper has a nice piece of plastic to hang it from.
*fuel- run a cetane booster/anti-gel especially this time of year. Conditioned fuel is happy fuel.
*your 285's create more drag and threw your speedo off about 4mph. Sure the problem doesnt lie there? Find a set of 235/85R16's and use them instead.
*intake- throw that K&N squirrel trap in the trash, do the DIY Tymar intake.
*exhaust- low restriction muffler is a must.. chrome plated fully illuminated genuine accessory exhaust systems are not; Flowmaster or a Dyno Max will suffice. (the biggest exhaust restriction on a SD is the turbocharger anyway)
*aerodynamics- solid tailgate
*aerodynamics- get a hunk of old conveyor belting and make an air dam & skirts that hang down at least as far as the axles do. The front bumper has a nice piece of plastic to hang it from.
*fuel- run a cetane booster/anti-gel especially this time of year. Conditioned fuel is happy fuel.
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Hoosier Golfer
SDD Junior Member
Thanks Guys!! Can anyone give me a heads up on the DIY Tymar intake (supplies needed, type of filter, installation instructions) Looks pretty cool from the few photo's i've seen, just need a little guidance to get me going the right direction!!! Oh,,,,, can i use the air inlet tube off the K&N and trash the rest of that piece of 
!!!?? THANKS FOR ALL THE HELP!!!!
!!!?? THANKS FOR ALL THE HELP!!!!
Zookie400
I WANNA GO FAST
i dont have time at the moment, but if you do a search for DIY TYMAR there have been a few threads that have part numbers for every brand of filter, as well as a how to.
