I've got pyrometer, boost, trans temp, and oil temp, although only the trans temp is actually hooked up. the truck blows a little black smoke if i really hammer down, but only for a second or two and the exaust has soot in it obviously. one of the valve covers leaks a very very small amount of oil not a noticable amount even after 5k, and never checked my brakes they seem ok though

 

I'm reminded of one year when my son had a job to feed the neighbor's barn animals. I pointed out they didn't have enough water and his reply was "They didn't die". Well, that prompted a conversation about the difference between "not dead" and not suffereing.

Your truck is suffering from something. If the brakes are not on fire and sparks aren't shooting out the back... well... then it ain't dead. That doesn't mean they don't need inspection... particularly of the slide pins.

A pyro is critical when running a hot tune like 80E or Race. Now... I'm about to say something that can be read as offensive, but it's not meant to be that way: Since you are new to diesel with a hot tune in a Superduty, I'll bet good money you've been hammering the skinny pedal on the right... screaming "Yee Haww" all the way. This would be a normal reaction by the uninitiated. Now you very likely have boost/exhaust leaks, and possibly a clogged air filter... maybe a sensor or two needs attention as well.

We can tell you the easy answer - run the 60E tune and keep your foot out of it. But we can't help you fix the complex machine that is the 7.3L turbodiesel by saying something like "Oh, it's your muffler bearing. Replace it and you'll double your mileage". Symptoms and sensor readings are needed to figure out what's going on with the truck. There is a good group here and we can help... if you help us to help you.

Welcome to FTE!

 

i got a k/n air intake, but how would i know if the filter was clogged and if there was a leaky boost, and the exhaust it almost brand new 4 inch turbo back dual

 

Without a working boost gauge, it's not as simple as stepping on it and see how high she goes. There is a "boost leak detector" that many members build for about 5 bucks. If you do a search on the forum, it will pop up a gajillion times.

The exhaust pipe is after the turbo. There is no pressure to lose there. The driving force of the turbo is the backpressure before the turbo. Leaks hear will be noisy and leave soot under the hood. Soot under hood = bad.

Is the K/N the type you clean... or toss? 5K miles is about the time the 4 gallons of oil in there need to be changed out, that would be a good time to inspect/clean or replace the air filter.

Oil: Cars are one thing, but these diesels use oil to power the injectors. Letting the oil go for very long miles or time carry very expensive consequences. If you have dead dinos, many change it at 3000 miles, some at 5000 miles. If you have synthetic, many change at 5000, while some change at 7000. Extend the life of the oil at your own risk... and that of your wallet.

Inflate your tires to rated pressure on the tire... or close to it. The tire place puffed my tires up to the door pressure, I bumped it up to just under the pressure listed on the side of the tire. Lower pressure is much more comfortable, but I took a measurable hit on fuel economy.

So... big tires? Can you get those gauges working? What kind of oil? Driving style (town/highway/both)? You have a 4.10 rear end on the truck, driving at 80 will eat you alive... the truck likes 65. The hard rule on the highway - keep the RPMs under 2000 or just pay for the pleasure of going fast. Trucks suck fuel. You have a particularly big truck. You can do some repairs, mods, and ajustments (to the truck and to your driving) in an effort to achieve 17-18 MPG.

 

How much boost should I have? The highest I've seen is 16 PSI. I'm still getting reasonable fuel economy 17-18 mpg.

 

No big tires yet, im working on getting those gauges hooked up pretty soon, not sure what kind of oil, town driving not very much highway at all, not sure about the air filter whether its cleanable or tossable, and i dont know about the rear end. i dont recall and soot under the hood from the last time i looked

 

A 6.0 at my work has a built in dash gauge from 0-40 psi and it rarely goes above 20 unless your running foot to the floor even then its not much over 25, my truck's (non- working) gauge goes from 0-60

 

A 6.0 at my work has a built in dash gauge from 0-40 psi and it rarely goes above 20 unless your running foot to the floor even then its not much over 25, my truck's (non- working) gauge goes from 0-60

 

Turbo back exhaust is rather non relevent to whats going on...

Take a look at where your up pipes connect at the back of the turbo...
Look for soot... if there is any at all... there is a leak, and you are losing drive pressure to the turbine.

Maybe start a new thread if you havent already...

 

just skimming thru random posts and ran across you guys chatting about tire size and mileage i didnt read them all but i didnt see any post about programming speedo for bigger tires . you can take it to ford dealer and have it adjusted to your size tires so speedo is correct . my buddy is going to do mine soon as my new tires come in atm im running 325-85r16 comes out to a 37-38 in tire im dropping to a 36-12.5r17 tire with a 8 in lift just because of illinois lift laws im illegal and tryin to get a little closer so cops wont mess with me hopefully. btw i just bought this truck i didnt lift it but couldnt pass this low mile beast up from florida

 

On this recommendation, I know there are weight tables for determining what pressure to use. Max or near max sidewall pressure in an unloaded truck will likely wear out the center of the tire before the edges. But given we're talking mileage in this thread, I agree max pressure would yield higher mileage, at the cost of early tire wearout.

Getting the truck weight per axle would be good, and get the tire manufacturers tables to determine your best inflation pressure. I run 55 in the front of my F350's 80 psi max Michelins, and 45 in the back unloaded, up to 80 loaded. When switching to my M143 Toyo 19.5's in the summer, they have a minimum pressure of 80 when unloaded, so they run hard, but I still run the rears to 120psi when the camper is on, using every bit of their weight rating (H).

 

While driving combined city highway driving in Colorado I was getting right at 17.6. Just drove a 17' camper weighing 3400" cross country to Maryland for 2400 miles. Driving over the mountains I was getting 7.8. On level straight aways at 75 I was getting 9.5. When I lowered speed to 70 I started getting 11. I was really expecting to get about 15, but the damed trailer, though light, is nothing but an air brake. At 60, got 12.8.