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General 6.4 Modifications

307115 Views 299 Replies 83 Participants Last post by  TJ Sim
It seems there have been a lot of threads recently about bulletproofing a 6.4 or what general modifications should be done to keep a 6.4 running well, so I am putting this together so we can get most of the information unified.

First and foremost with these engines, maintenance is crucial. Change your oil and filters on time and with quality oil. Only use Racor or Motorcraft filters. Change your fuel filters (there are 2 of them, one on the top of the motor and one on the frame on the drivers side). Empty the water separator (its on the fuel filter on the frame). When changing fluids use quality fluids for everything, i.e. transmission fluid, differential fluid, oil, coolant, etc. It is also suggested to run a fuel additive when filling up your fuel tank (I am not going to get deep into this as there are tons of additives out there and tons of discussion on it).

Ok now for the fun stuff. There are all sorts of levels to modify your truck, and I promise once you start you will get bit by the M.A.D. (Modification Addiction Disorder) bug.

**I have also noticed a trend in some of the questions, if you are not mechanically inclined, most of the modifications are not difficult to accomplish (at least the basic bulletproofing ones) and feel free to keep asking questions (in this thread and also in your own build threads), but as a note, DO NOT PUSH THE LIMITS OF YOUR TRUCK IF YOU DO NOT KNOW HOW TO FIX IT. These modifications can be great bulletproofing measures when the power level is increased in moderation. Don't expect to do the bare minimum and more than double the power output of the engine and go stoplight racing your buddies in their Mustangs or Camaros and not break something.**

1. Tuner: there are a few out there, but the most popular are the Spartan and the H&S - Offroad (Mini Max, XRT Pro). Custom tunes can also be had from Gearhead performance and Innovative Performance and will be uploaded via an SCT. Custom tunes can also be had from KEM. At the moment these will give you the option to delete the DPF. Recently people have been looking for cheaper options as Spartan and H&S tuners are now becoming very expensive. DPF-r is a basic tuner that allows the DPF to be removed. The DPF-r 4.0+ also adds a small amount of HP (70HP). I do not have any personal experience with the DPF-r, but here is a recent review by another member.

This will allow you to get rid of the Regen cycles. There are a few benefits to this.

****Edit: H&S no longer produces off-road tuners for the public. The old tuners can still be found with some searching, but will be expensive now. If you can provide a reason for having DPF-delete tunes to the EPA you can still get them, but as I understand it is nearly impossible for us in the United States.****

****Edit: Also be sure you purchase an off-road SCT tuner if you choose to go this route. The Competition SCT Tuners also do not accept custom tunes.****

First your fuel mileage will increase because the engine is no longer dumping fuel into the exhaust stroke to be burned in the DPF to clean out the soot it has collected.​

Second it will lower your fuel dilution because fuel won't be dumping into the engine on the exhaust stroke.​

The tuners will also allow you to run much higher horsepower tunes on your truck (just be forewarned, the higher the tunes the more modification your truck will require to stay bulletproofed).​

INSTALLATION: This one is easy. Plug it in to your OBDII port, follow the instructions on the tuner and it will walk you thru the installation. NOTE: DON'T INSTALL A "DELETE" TUNE (either deleting your DPF or EGR) BEFORE PERFORMING THE DELETE!​

2. Exhaust: There are a few options at this point.

A DPF/DOC delete pipe is the minimum and the cheapest option for removing the DPF. This is just a short straight pipe that takes the place of the DPF and DOC.​

After that there are all sorts of options for full exhaust.​

First you must decide if you want to get a downpipe back or turbo back. The stock downpipe is very restrictive but in order to remove the stock downpipe it must either be cut or the cab removed. The replacement downpipe is usually a 2 piece so it can be put back in cab on and is not very difficult to install.​

The next question is 4" or 5" pipe. I have noticed that most people who buy a 4" pipe eventually switch to a 5" pipe. The 5" has a deeper sound to it and a little less whistle. I haven't heard of anyone noticing a difference in performance between the two, it comes down to personal preference.​

Last, muffler or no muffler. The turbos in the 6.4 quiet the motor a lot, to the point that a muffler really isn't needed. It is also personal preference. I'm sure having a muffler might take some more of the whistle out of the exhaust note.​

As far as material, I would think it depends on where you live, if you live farther north and the roads are salted in the winter, spring for the extra price and get the stainless rather than the aluminized.​

INSTALLATION: Exhaust Installation

3. Intake: There are all kinds of intakes out there. By far the 2 most used brands on this forum are S&B or AFE. Either will do the job on your tuned 6.4. The stock intake will work for lower HP tunes, but once the high HP tunes are loaded up there is too much air flowing and the filter minder will pop every time you roll into the throttle a little. The only other options here are wet vs dry.

Wet requires cleaning when it is dirty. Dry is just replaced.​

4. EGR delete: There are also a few options here. The 6.4 EGR coolers are better than the 6.0, but it is still a point of failure. AND the EGR system puts soot and other crap back into the engine. Just take a look in the air intake manifold of a 6.4 that has had the EGR intact for a long time, its caked with crap.

Option 1: turn off the EGR with a tuner. This is usually done on the higher tunes. Everything is still intact, but the crap isn't being cycled into the engine. This is byfar the bandaid fix and I wouldn't recommend it as a final solution.

Option 2: Block off plates. These can be installed on both sides of the EGR coolers. This is the cheapest and easiest solution but is still not a perfect solution. Coolant still flows through the coolers, but exhaust gas doesn't flow through. A tuner is also required for this.

Option 3: The 100% solution. Completely remove the EGRs with an EGR delete. These kits come with block of plates for the exhaust and the coolant. This takes time to do (usually most of a day). I suggest getting a kit that has an intake elbow to replace the EGR valve. This requires a tuner as well. FloPro, Sinister and PTP make quality kits.​

INSTALLATION: EGR Delete Instructions

That is the minimum. There are plenty of other modifications that can assist.

5. CCV mod: CCV stands for Crank Case Vent. Ford designed your oil crank case to vent into the intake. This is the reason there is oil in the intercooler or in the intercooler pipes. There are a few options for this mod.

First an open air vent: Run some heater hose from the crank case down to your frame rail and put a small filter on the end. Cap off the air intake connection. This is by far the cheapest and easiest option, however it tends to smell and you leave puddles where you park.

Second a catch can: Run heater hose from the crank case to a catch can with filter material in it and a return line to the air intake tube.

Third vent to exhaust: This requires a little fabricating skill. There are some kits out there if you look. Or it can be done DIY. Basically it requires welding on a bung and running a hose from the CCV to the bung on the exhaust. THIS IS NOT RECOMMENDED UNLESS YOU GREATLY UNDERSTAND THE VENTURI EFFECT. If this is done incorrectly pressure could build on the exhaust side and cause excessive pressure in your CCV.​

6. CAC pipe: CAC stands for Charge Air Cooler. This is the pipe on the cold side of your intercooler that goes to your turbo. Instead of changing the design to allow a circular pipe to be installed, Ford just crimped the pipe, making it restrictive. An aftermarket pipe can be installed with minimal trimming of the radiator support or some can be installed with no trimming.

INSTALLATION: CAC Pipe Instructions

7. Coolant filter: the 6.4 engine block was sand cast and therefore overtime sand that was still in the block seeps into the coolant. There are a few brands: DieselSite or Sinister

8. Aftermarket Fuel Filter: I wanted to start with a little description of the 6.4 fuel system, but this thread has too many characters. Here is a link to a new thread: 6.4 Fuel System

You have 4 main options: FASS, AirDog, Aeromotive (A-1000), or Fuel Lab
FASS and AirDog: Both of these companies make LP systems specifically for a 6.4. These are the cheapest options and are quite effective at water separation and filtering out other impurities. Their biggest disadvantage is there have been a decent number of these that fail suddenly and without warning although many do hold up reasonably well. Typically, you want at least 150 GPH rating on either of these.
Aeromotive: The Aeromotive pump (A-1000) has the ability to supply a lot more than fuel than other LPFP available. This does seem to allow it to last longer than the AirDog or FASS because it is not working as hard as the other pumps to supply fuel. Aeromotive never made a kit specifically for the 6.4 so you will have to add a bracket to hold the water separator (pre-pump), the A-1000, and the filter for impurities post-pump. There are a few kits available if you don’t want to make your own brackets and assemblies. The two most commonly used are Elite’s Stage II LP system and Marty’s Diesel LP system. Marty’s kit does allow you to use CAT filters and have a 2 micron filtration rating.
Fuel Lab: Fuel Lab also does not make a kit specifically for the 6.4. There are a few companies that have made a kit so that you can run a Fuel Lab on the 6.4. To date, Midwestern offers a kit and bracket for these pumps on a 6.4. Also, Fuel Lab is working directly with Side Action Diesel so that Side Action can offer a kit for the 6.4 although technically, the entire system is not made by Fuel Lab. This kit is expected to be released in April or May of 2014. The biggest advantage of the Fuel Lab pump is that is uses a brushless motor (unlike any of the others) so there are no brushes to wear out over time.​

Additional info:
Fuel Bowl Deletes: These really aren’t needed if you have a stock HPFP and injectors. They only benefit they provide on stock applications is they eliminate clutter in the engine bay, they eliminate one more part that can fail, they save you from having to buy both filters and only using the engine filter (assuming you have replaced the LP system, and they can make diagnosing a fuel problem easier.
Nozzles: With a single stock HPFP, the stock nozzles are basically maxing out the capabilities of the HPFP. If you decide to upgrade to a larger nozzle (even just 15% nozzles), you will have to modify the HP system or cut the PW to maintain RP at WOT on race tune (PW of 2.2 to 2.3). The only options available for modifying the HP system are a modded K16 or dual fuelers. The only modded K16 that is available is made by Industrial (II) and it is notorious for grenading and taking out the injectors, rails, etc. when it does.​


For parts and installation of Aeromotive and Fuel Lab filters you will have to do a little research and google yourself.​

9. Aftermarket intercooler: an aftermarket intercooler will lower your EGTs. If you tow heavy or like to race, this will benefit you greatly. Otherwise, it is not a requirement. Spearco, AFE, and No Limit make quality intercoolers. This is a 10 minute installation.

10. Intercooler boots: stock boots are short and breakdown over time with oil (CCV mod prevents the oil). Boots from are also longer and are rated for higher pressure than stock. These are also not a requirement for bulletproofing, but they have benefits.

11. Turbo Socks: These cover your turbos and replace the factory heat shield. When I added mine I did notice slightly lower EGTs and quicker turbo spool time. It can also be used along with using Titanium header wrap on the down pipe. Again this is not a requirement, but for $100 I noticed some benefits and it cut down on my smoke output.

12. Traction Bars: on higher HP tunes this is a HUGE suggestion. Traction bars eliminate axle wrap. Without the bars, when you slam on the throttle, the tires rotate forward and the axle wants to rotate backward. This makes the leaf springs want to make an "S" shape. Because of this, the driveline tweaks and shifts are harder. The leaf spring also wants to get back to its original shape which creates wheel hop. Traction bars keep the axle from rotating and therefore smooths out acceleration and shifts while accelerating. There are plenty of manufacturers out there (PrecisionMetalFab, CalTrac, Newton, etc.)

The next modifications are definitely not a requirement to bulletproof, but will significantly improve the reliability and durability of your 6.4 engine, especially when loading higher HP tunes.

13: Head Studs: 6.4 headstuds are much stronger then the 6.0, but they can still be stretched and cause head gasket failure. I have heard of them being changed cab on, but it is suggested to do a cab off installation so the heads can be removed, magnifluxed and new gaskets can be installed. Use ARP studs, OEM gaskets and a reputable truck shop to do the work.

14. Transmission: The 5R110 is a great transmission and is very strong, but at HP and TQ levels double factory output, it is on borrowed time. If you are tuning to the high HP levels, eventually you will need a new torque converter (RCD or SunCoast). Billet Shafts are also recommended.

15. Intake/exhaust manifolds & Up pipes: if your wallet can handle it, while the cab is up for the Head Studs I would throw on aftermarket manifolds & up pipes that flow better. The easier you make if for the engine to flow air the more efficient it can be.

Do all these need to be accomplished to make your 6.4 run well and forever? No. Will they help to make your 6.4 last forever? you bet! These are just suggestions to start and I'm sure there will be more who will chime in on their suggestions.
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Amazing! This should be a sticky:thumb:
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Very well put together.

Thanks for putting your time into this.

It's nice to have an "Engineer Nerd" on our forum.(haha)
Nice write up. It is put together very well and is informative and answers a lot of the questions asked in this section. Definitely worthy of the sticky!
Nice write up... I thought I was done with the egr/cooler, dpf delete, elbow , coolant flush, Afe Intake, H&S and the traction bars I just ordered today... But after looking at this I still got some work to do LOL
Nice write up CountryAggie! :thumb:
Nice but CAC stands for Charge Air Cooler
yep. you are right. Fixed it... I spent about an hour writing this while watching a movie with my family. Sorry if there are some misspellings, grammatical errors or wrong acronym definitions. I hope I didn't make many, but hey, we are all human right?
Lol you did much better than most would have done. This should help a lot of people out. Now if there was just a way to force people to read this any time they want to start a thread about "what should I do to my truck to make it better"
Great write up Tyler!
4" exhaust here and zero desire to go to 5"
I said "most"... And "personal preference"....

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My bank account weeps from seeing this!
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Tyler, do u recommend doing them in the order listed?
Not necessarily. I started the list not intending that, but it is kinda how my truck is going to end up being done, I think. In reality not everything here is required for everyone, it depends on how you intend to use your truck. I would say the first 8 are highly suggested. Everything else becomes more and more necessary as HP goes up.

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Nice write up . I just bought a 2008 F-350 CC Dually and am getting ready to mod it . Definately should be a sticky .
I need to do the CCV, CA cold side and inter cooler. Dang it Tyler! They say ignorance is bliss. Bliss is steadily going down! Great info man!
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