Help with mileage.

[Scotty.92]

C1500 RCLB
I am wanting some input on my truck. I can get about 85km using 1/4 tank with the 38 gallon tank. Truck is a c1500 with 235/75/15 tires I think, and cruises at right around 1600 at 100km. Might be at 1800-200 at 110km.I usually drive at 110km/h and I think I get right around 10/11 mpg with my truck. highway

I don't think this is right for the truck and should get more than that! I know; it is equipped with roof visor, bug deflector, tires a little low, vent visors, about 300/400 lbs of gravel in back for winter, 325,700km on it, what sounds like a bad u-joint, and a real nasty misfire that I can hear/feel in the truck which do not help mileage.

What can I do to get better mileage? Only thing I wont do is take the vent visors off, and the roof visor. I have a very light foot. I can`t really afford this mileage as a student, I might as well drive my 1980 Trans am that probably gets 14 mpg. I know the motor has lots of life yet because has no signs of high mileage wear except a little leak that has been taken car of.


**I`m not expecting huge mileage because these trucks are just bricks in the wind**

 

[Ruger_556]

Check you mileage at the pump not with the fuel gauge... Other than that fix the misfire and tires at 35 psi (If they're P-metric).

 

[Scotty.92]

We had done this and got 13.66 mpg a while ago. I know it is not quite as good now.

-Any help on the misfire? It just sort of came about. I have already changed plugs, dist cap, and rotor. The misfire happened a while after I changed them, was just doing regular maintenance. I will pull a plug and see what it looks like.

 

[SkyHighColorado]

Replace coolant temp sensor, oxygen sensor, fuel filter (wix), change to all synthetic fluids (diff, trans, engine, get nice spark plugs. I run autolite Xp iridium enhanced at .035 gap, runs way better than with acdelco standard. Jump a+b ports with paper clip and check for codes then fix any that show up. Advance timing a little, get a new cap and rotor and coil. 35psi is pretty low for me, I run 48 psi. An alignment would help. Your visor is causing drag (but you like it) put valance on if it's not alread. Replace pcv. Check for vacuum leaks. Do seafoaming of top end through brake booster and tbi (best before plug change) most importand things are tire pressure ands coolant temp sensor. Hope that helps you out a little. I missed a lot more things that help with mpgs like new air filter etc.

 

[Scotty.92]

Replace coolant temp sensor, oxygen sensor, fuel filter (wix), change to all synthetic fluids (diff, trans, engine, get nice spark plugs. I run autolite Xp iridium enhanced at .035 gap, runs way better than with acdelco standard. Jump a+b ports with paper clip and check for codes then fix any that show up. Advance timing a little, get a new cap and rotor and coil. 35psi is pretty low for me, I run 48 psi. An alignment would help. Your visor is causing drag (but you like it) put valance on if it's not alread. Replace pcv. Check for vacuum leaks. Do seafoaming of top end through brake booster and tbi (best before plug change) most importand things are tire pressure ands coolant temp sensor. Hope that helps you out a little. I missed a lot more things that help with mpgs like new air filter etc.

Before you had replied I had done tune up maintenance such as: Fuel filter, air filter, spark plugs, cap/rotor, plug wires, filled tires, semi synthetic engine oil, (Now fixed my one code; EGR had a line broken so it wouldn`t work), alignment was just about dead on. Getting a new exhaust which should help? I`m going to the auto store tomorrow and pick up pcv and temp sensor.

 

[Scotty.92]

Sorry, meant to mention that it seems my mpg has gone up a bit but by how much; I don`t know. Thanks for helping with what to look at. Did buy ECT other day and PCV.