I don't think you'll have the same detergents/quantities in certain fuels. Check out Shell V-Power. Not the same as other 91-93 octane by a long shot. I use it once in a while. It even smells more awesome. The right fuel can help clean up deposits.

 

I FINALLY had a chance to change the plugs yesterday. I swapped the platinum plugs for a set of Bosch coppers from rockauto. I didn't use the autolite ones that are a range cooler since I haven't done any power gain mods and if I do then swapping plugs is relatively cheap and easy.

First test drive seemed promising but I won't say anything until a few days pass. Hopefully this solves the problem, but I'm going to have to remain a pecimist on this.

Thanks for the help thus far.

 

well did that work for you. the people i brought my new engine to put in ngk platinums and it is sucking gas like a fat kid drinks soda pop. my last engine with a terrible engine oil internal leak, knocking and noise only ever drank around 15-16mpg city after putting in champion copper cores.

 

Ok sorry for the slow progress but I've not actually had regular access to my truck for quite some time and I finally have it back.

So after plenty of testing here are the results. I'm getting around 15/17. Around town the mileage is where it should be and I can keep it above 16 if I really try. However, the highway mileage is surprisingly poor and haven't really improved. I barely managed 18 on the interstate. The good news is that almost all the power is back, and considering has is only $2.43 a gallon where I live in happy with the mileage situation.

I think part of the reason the highway mingle is low is because the front end needs new hubs, has a bad alignment, and the tires are off balance. Unfortunately all that won't be felt with until spring or possibly later if I can peace-meal a lift together.

Thanks for the help. Anyone want 8 platinum plugs?

 

From my experience you are about as good as you'll get considering the 4x4, V8 and larger tires. At what speeds are you running on the highway? I can get almost 23mpg out of my 2WD quad with the 4.7 if I'm keeping it easy between 60 and 65. Drops like a stone down to about 19mpg at 70mph. At 75+mph I might get 17mpg.

 

I agree. That's the kind of mileage these and most trucks get. It's not going to get any better unless you run an entire tank at 55 mph without stopping.

These newer trucks that brag about 25 + are either diesels or gas engines with transmissions that drop the rpm's too low. Ours are well balanced for economy and durability, and the rpm's are where they should be. The trucks that lug around at 1200 might get better economy even with the pedal 1/2 way down or more, but the strain on the engine is way higher, decreasing longevity.