Bought a 1999 7.3 drw crew cab truck with 141000 miles on it about a year ago

Have hauled my 36' fifth wheek with it no problems and have put about 12000 miles on it.

Love the truck ...... and really no issues with it so far.

Fuel economy empty load ..... @ 2000 rpms 61 miles an hour 17.2 miles per gallon .... got 567 miles on one tank

Questions:

1)What preventive stuff should i do to this truck to contiune its good luck .....
2) not real happy with braking when hauling the fifth wheel .... brakes on the trailer are fine .... all new brakes as of when i bought the truck ... oem ford pads
3) I assume I have 410 gears ..... going to say a 373 gear or something like that since i drive the truck to work ... how bad will this effect hauling my fifth wheel ....
4) How do i tell if I have a programmer ... have no clue but the tech at the dealership i work for thinks i do... max psi i have seen from my boost gauge i think was around 15-17 psi

Many thanks !!!

happy 7.3 owner here!

 

Well lets see; How about, flush power steering, Change out rear diff oil, Change out trans fluid and flush, Just for starters.

 

I would check the air filter box for starters if it is still stock, they have been know to leak. you could look into an exhaust brake set up for your truck.. You will not like 3:73 gears for towing compared with 4:10 gears.It might be okay if you have a manual tranny. It also depends on whta size of tires you are running and how heavy the 5th wheel is. Mileage looks fine, you right foot works best for that. Look down near the parking brake on the floor and see if the PCM box has been opened and a chip has been installed.

 

thanks guys ...... i do work at a ford store .... and did the following

tranny flush with new filter .... new tranny cooler piggy back to stock cooler ... did the rear diff flush ... air box is a kn .... re oiled .... new fuel filter .. when i first bought the truck this was all done .... including some tires ... the brake job ..... door actuators ... power window motors .. etc .... only paid 8000 for a centurian package truck .... in great shape ... added another $2000 in repairs and maintance .... and LOVE THE TRUCK

 

I would NOT be running a K&N set up for an air filter. they just do not do the job needed for our trucks. Plenty of threads on this issue if you do a search and the vast majority are negative. The 6637 filter set up is popular but there are other set ups as well, although the 6637 is the cheapest route to go it will be a little louder.

 

this is the only problem I see in your mods. K & N is a great product, but NOT for diesels, our turbo's have too much pressure, and it can let lots of dust thru the filter. I suggest you pull the intake off the turbo and inspect the wheel, I ran a K & N for about 2 years before I found this out...and my wheel was dusted pretty bad. Lots of us run the 6637 filter on here, or there are many other options as well that will filter much better then the stock box, it has problems sealing the dust out to begin with, and the K & N won't help ya much either. You'll regret changing to 3:73 gears for towing, I have 3:73's and I plan on going to 4:30's sometime soon, but I have 37" tires. You're getting great mileage....I wouldn't change much!

 

Just want to add that 15-17 psi of boost is normal for a stock truck. Sounds like it does not have a tuner or chip. If your buddy thinks you may, then chances are your just have a good-running truck there. Nice find. I have 3.73 gears and am planning to swap to 4.10 for more towing power. I do not reccomend the 3.73 unless the vast majority of the miles you are putting on the truck are unloaded.

 

unless you changed your tire size by a few inches, you probably wont like a change in your gears.

brakes are what they are, you could try some drilled/slotted rotors for better cooling and i see alot of guys like hawk pads, i think you would be better off upgreading you valve body and downshifting with the trans/exhaust brakes.

If you really want better brake i saw a guy with an F450 front axel and has to run 20"s to clear the rotor, so thats always an option...lol

your techs at ford should be able to find a programmer easy, if ones is there, other than the boost gauge, is there any other signs of aftermarket stuff? exhaust? pyro? trans gauge? etc?

 

the retro fit of a F-450 front end might be the way to go for better braking ... did that with other vehicles .... find a wrecked 450 in the yard .... Also thanks for the KN tip ... where can I get the 6637 air filter .. pls note I have no factory box ...previous owner removed it ... and i run the kn stand alone

 

Give Clay an email or call him at Riff Raff Diesel.He is one of our site sponsors with great service and prices.

 

Riffraff Diesel: RDP 6637 Filter Kit If you have the K&N cold air intake your in good shape.... but the flat pannel K&N that goes in the stock air box is the one that you want to change out

 

X2....I ran the K&N stand alone for 250000 miles, no problem at all, just keep regular maintance

 

some pros and cons on the KN ..... but id rather err on the side of being safe. The airbox mentioned here obviously does the job ..... so i will call fred

I may want to do some mods on the truck .... as most can see my screen name ... my other toy was a 07 Shelby Gt500..... but i decided to downsize and sold it a few mths ago ... so I want to put my energy and efforts from the team shelby forum to this one .... and start modestly modding my truck ..... where to start where to start HA

 

ps ..... the mods that I know the truck has is a 3 pod gauge set .... boost .... tranny temp gauge and the pyro thing ... that measures exhaust gases i think .. that gauge isnt working ... think i need new sensor .... one of the things i am going to get around too eventually

MY computer behind the brake pedal has a plastic casing around it so i cant really see any programmer hooked to the pcm ... however i do see a wire going into it that tells me it could have a chip ... tried to follow the wire but the previous owner of this truck who died put lots of stuff in this truck ... there are so many wires that are cut and I have no clue what they are for ..... his dad than got it and he traded it into our dealership ... truck has HD headlights ... tv antenna and coax ... dont know what he hooked up ... he had XM radio .... that i used his wiring to hook my radio up to .... has a airhorn ... the guages... special lighting and like i said its a centurian coach ... the truck once it was built was sent to them .... real nice seats .... great great truck ... love it .... but i do think i want to start modding it ... and need to get more active with this forum to find out where i start .... i will tell people one thing about me ... im real **** about gas mileage .. so the mods i want would be to help that ... exhaust system maybe ?

 

Theres a good chance that you just have faulty wiring on your EGT gauge follow the wires and make sure there all in good shape its not common for the EGT probe to go bad unless the wires got pulled out of it. Your gonna want that gauge more that you know.

You should only have a plug on the back of your PCM if theres no tuner or programmer hooked to it.

You can do an intake and exhaust but you proably wont see much of a mileage improvement at 17.2 MPG your already at the high end for these 4wd trucks. If you only have a 2WD theres room for improvement, not much but there is.

Everything in my signature has not yielded me any improvement in MPG not even the tuner, but they havent hurt my mileage at all either, I just make A LOT more power.
If upir truck is tuned any you dont know it you could have the same issue Im in the middle of now too, you could have blown uppipes and leaking manifolds. With my tuner Im still only making about 18psi boost, I should be making much more than that. Look at your fire wall and see if you have soot build up on it, and get under the truck with a flash light and see if you have soot build up anywhere on the uppipes youll be able to see the bottom of the turbo where the uppipes run to on the driver side threw a small window, not so much on the passanger side though. Look really close at your manifolds too at the heads you may see a slight bit of soot there too like I have, there are pictures here somewhere that can help you out if his wasnt detailed enough, good luck