6.0 Ford Diesel Engine & FICM Questions

SponsorOPTIMA Batteries
LocationCaledonia, Wisconsin
DateMarch 10, 2014

Much has been written over the years about Ford's 6.0 diesel engine and I (OPTIMA Jim) have read most of it, as I happen to own a 2003 Ford Excursion, that I ordered with that engine (the 7.3 diesel was also an option when I placed my order). While some folks have been less than pleased with the performance of their 6.0 engine, I've really been happy with mine.

I am now closing in on 240,000 miles and as winter and colder weather come in, it becomes time to once again plug the truck in, so cold starts, well, become warmer. When I don't have the luxury of a nearby electrical outlet, it does get me thinking about the state of health of my FICM (fuel injection control module). Believe it or not, I'm still on the original module, which I attribute to my track record of long and healthy battery life.

My original set of OE batteries lasted until early-2008, when I swapped them out for a brand-new set of Group 34 REDTOP batteries. I used those batteries until June of 2012 and only swapped them out at that time, because I encountered two owners of GM vehicles on the HOT ROD Magazine Power Tour, who needed replacement batteries for their vehicles. Their particular batteries were connected at the side terminals and because they didn't have a solid connection, the one spot where electricity could travel in and out of the battery became very hot and melted out the lead in their side terminals. The batteries still functioned perfectly fine from the top terminals (which are the terminals my Excursion uses), so I simply swapped out their batteries for mine and finished Power Tour on a mis-matched set.

Whenever multiple batteries are run in series or parallel configurations, they should always be identical in age, size and type. Because the age of the batteries I swapped were different (as well as their previous applications), I elected to install a fresh, matched pair of D34M BLUETOPs that we happened to have on hand after I returned home from Power Tour, although it took me a few months of running mis-matched batteries before I got around to it (shame on me).

I share that story, because I want to illustrate that I haven't exactly been nice to my batteries over the years, but I do try to maintain proper voltage whenever possible- (about 12.6-12.8 for REDTOPs (and the 34M BLUETOP) and about 13.0-13.2 for YELLOWTOP and BLUETOP batteries (except the 34M BLUETOP). Maintaining proper voltage whenever possible will help maximize both the lifespan and performance of any lead-acid battery.

We print our 800 number (888-8-OPTIMA) and e-mail address (info@optimabatteries) on every battery we sell, but sometimes folks prefer to click on the image of me carry bags on the side of this page and ask me a question directly, which I answer here. Today's question comes to us from Chuck, a fellow 6.0 owner:

I have an F250 6.0 diesel and have two fairly-new OPTIMA REDTOPs. My mechanic said because the cranking volts (we think he meant amps) are lower than 1000, it could possibly damage the fuel injection control module (FICM). Once the truck is started, the amps go up to a satisfactory level. The voltage drops to 11. something but goes up to 13.5 when running. My mechanic said the draw on the batteries is very high in this type of application and they won't last more than 18 months. Is that true?

Well Chuck, I can tell you from personal experience, that my batteries, both OE and OPTIMA have lasted far longer than 18 months. However, there has been a lot of discussion about the FICM and how good battery health relates to the lifespan of your FICM. I somehow have managed to run nearly 240,000 miles on my original FICM, although from everything I've read, that sounds like it could be 100,000 miles or more than what most folks get out of their units.

When the FICMs die, it is often a slow, painful death that may go unnoticed by the owner until the truck just doesn't run at all, perhaps damaging injectors along the way. I think I'm headed in that direction with my Excursion, so a new FICM is on my short list of new upgrades. Our friends at Diesel Power Magazine have actually written about this very concern with FICM units and the 6.0 engines and there are some very economical (compared to dealer prices) options for replacing these units. One of the recommendations in their FICM article is to make sure your truck's charging system is always functioning properly, which may be where your mechanic was headed in expressing concern about the health of your batteries. Four Wheeler magazine also wrote an FICM article recently on yet another alternative to the factory unit from Bullet Proof Diesel.

If your 6.0 F250 was like my Excursion, it came from the factory with a matched set of flooded batteries rated at 650 cold cranking amps. The 800 CCA REDTOPs I replaced them with far exceed the manufacturer's recommendations in that regard, so cranking amps shouldn't be an issue. However, if there is a concern regarding the health of your batteries, you can always have them load-tested, which will give you an idea of their general health. Many auto parts stores offer this service and some will even do it for free (I carry a load tester in my Excursion and do it for free all the time). Some of these units will even be able to measure the actual cold cranking amps of your battery. It is not uncommon for our batteries to actually test higher than their specified ratings, although I would encourage you to make sure your REDTOPs are fully-charged (~12.6-12.8 volts) before load-testing them.

The other component of your truck's charging system is you alternator, which does the heavy electrical lifting after the engine is started. I believe my Excursion came from the factory with a 95-amp alternator. It did it's job well for just over 200,000 miles, but when it came time to replace it, I opted for a serious upgrade in the form of a 200-amp alternator from Powermaster. Our friends at Powermaster tell us OEs will claim alternators are designed to operate at about 80% of duty cycle, but they typically see a number closer to 60%. My Excursion is not very complicated or demanding from an electrical standpoint, so the 200-amp unit should have no trouble handling anything I throw at it. If you run a winch, lots of lights, a big stereo or other significant electrical accessories, you may want to consider upgrading your alternator and wiring.

If you are only seeing 13.5 volts out of your alternator, it may be time to take a closer look at it. We typically suggest a range of about 13.7-14.7 volts for alternator out when the engine is running and 13.5 sounds like what my alternator was putting out right before it let go. You can also have your alternator tested, which may not be a bad idea either. All of these components are connected to each other, so it is a good idea to make sure you've covered all your bases.