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Fixing Factory Mistakes - 1999 - 2004 Ford Super Duty Trouble Spots

Improving What The Factory Missed

Ali MansourPhotographer, Writer

When Ford unveiled the ¾- and 1-ton Super Duty line in 1999, it was an immediate hit with truck enthusiasts across America. With a spacious cab, powerful 7.3L diesel engine, leaf-sprung suspension, and front and rear solid axles, the Super Duty platforms offered something for nearly everyone in the heavy-duty truck market and even enticed first-time buyers with plush interior finishes. Fast forward to today, and the first-gen Super Duty trucks continue to thrive and have an abundance of aftermarket support.

So, how then does the Super Duty make it in our Fixing Factory Mistakes section? The simple answer is that there is no such thing as a perfect truck. Regardless of how many are still on the road today, there are a few items we would upgrade or be on the lookout if we owned or were looking to swap into one. We’ve limited our trouble spot list to the ’99-’04 first-gen ¾- and 1-ton 4x4 models, as they are some of the most commonly found and affordable.

The Problem: 6.0L Head Bolts
Much to the dismay of 7.3L diesel enthusiasts, in 2003 Ford made the switch to an all-new 6.0L V-8 diesel engine. It didn’t take long for the first of a few issues to arise with the fresh powerplant. Probably the most well-known and problematic is the issue with the factory head bolts. Essentially, the bolts stretch, which results in a blown head gasket.

The Fix: ARP Head Studs
ARP (Automotive Racing Products) (www.arp-bolts.com) offer head studs that replace the faulty bolts. The stud conversion is very straightforward, but extremely time consuming. Most diesel shops we spoke with actually raise the body from the chassis to gain access to the engine.

The Problem: Vacuum Leak
Although the Super Duty uses unit bearings up front from the factory, the trucks are still equipped with selectable hubs. Many of the early trucks were equipped with Ford-specific hubs which had an auto and on setting only. These hubs were vacuum-assisted and known to be problematic. A leaking or dry-rotted vacuum line is not uncommon to find, nor is a damaged hub actuator. Pictured here is a quick trail fix that uses a stick to plug a vacuum line that was leaking and no longer needed because the truck was outfitted with aftermarket hubs.

The Fix: Warn Hubs
It’s never a bad idea to make sure all of your vacuum lines are in good shape. Age and heat can break down a stock hose and often create havoc on the four-wheel drive and HVAC system. Upgrading to a set of Warn (www.warn.com) Premium Series hubs is another worthwhile investment. If you do opt for the Warn hubs (PN 38826), be sure to plug the hubs original vacuum lines.

The Problem: Front Unit Bearings
Big tires and unit bearings don’t always mix well. Even in the factory configuration, the non-serviceable unit bearings have a limited life cycle. The easy way to check for a bad unit bearing is by jacking up the front axle, one side at a time. You’ll want to raise the tire off of the ground enough so that a prybar can be placed under the bottom of the tire. You can also use your hands to test this, but the prybar will give you extra leverage.

You’re looking for major camber change in the wheel. If you find that the camber is changing drastically and/or the wheel seems wobbly, there is a good chance that the wheel bearings are toast. Be sure to check that the ball joints are in good shape as well, as they are also common wear items.

The Fix: Dynatrac Free-Spin Kit
Replacing worn parts with factory-style replacement parts is always a simple and easy option. That being said, replacing the faulty parts with the same type might not be cheaper over time. We are fans of the Free-Spin kit from Dynatrac (www.dynatrac.com) as it replaces the stock unit bearings with a serviceable full-float spindle, along with Warn Premium Series hubs. The Free-Spin kit is also rated for up to 44-inch tires and allows you to retain your stock wheel bolt pattern.

The Problem: Carrier Bearing
The four-door crew cab models were extremely spacious, but the long wheelbase came with a carrier bearing driveline support. The carrier bearing union that supports the two-piece driveline is notorious for wearing out and causing driveline vibrations. A lifted Super Duty or one with an incorrectly spaced carrier-bearing drop will aggravate the situation and increase wear.

The Fix: Replacement Bearing
Assuming that your driveline joints are all in good working order, most trucks simply need a new carrier bearing. The part can usually be ordered from your local parts store or driveline shop. We suggest having the driveline balanced and inspected if you feel tremendous vibration on a non-lifted truck.

The Problem: EGR Cooler
The 6.0L diesel has a bad reputation for blown head gaskets and sticking EGR (exhaust gas recirculation) valve. While stretching head bolts are partly to blame for the head gasket issue, programmers that turn up the power in your 6.0L truck are guilty culprits as well. Simply put, the stock EGR cooler cannot keep up with filtering a modified 6.0L. A failing EGR cooler can cause your truck to overheat, run poorly, and add to the potential for head gasket failure.

The Fix: Performance Cooler or Delete
For the most part, you have two EGR cooler options. The first option would be to delete the cooler in its entirety with one of the many delete, bypass, or block-off kits offered in the aftermarket. This would be considered a competition or off-road only conversion as it would require removing emissions equipment. The other option would be an upgraded cooler, such as those from BD Diesel Performance (www.dieselperformance.com) and Bullet Proof Diesel (www.bulletproofdiesel.com). The high-flow coolers are designed to improve flow and reduce issues common with the factory EGR cooler.

The Problem: Fuel-Water Separator
The fuel-water separator drain valve is a common culprit for leaking diesel fuel on top of the 7.3L diesel engine. Located on the backside of the fuel filter housing, the drain valve has two O-rings that can go bad over time.

The Fix: R&R
We’ve actually experienced this issue firsthand, and found a Ford dealership was the most efficient way to get the right parts we needed.

The Problem: Dana 50
We struggled with whether or not to call the Dana 50 a factory mistake, but given that it is not as strong as the Dana 60 and was ultimately discontinued, we figured you should at least be aware. Stampings on the front and back of the differential will indicate whether you have the 50 or 60. The 60 also has a longer pinion snout. Early ¾-ton trucks are the mostly likely to be equipped with the Dana 50 front, as they were eventually phased out in 2003.

The Fix: Dana 60
If you plan on fitting your rig with tires over 37 inches, then swapping out for a Super Duty Dana 60 is worth the hassle. Since the conversion is mostly bolt-in, there is no need to sub out the job to a shop. We recently covered the 50 to 60 Super Duty conversion (“Dana 50 to 60,” Sept. ’13), and the article can now be viewed online at www.fourwheeler.com.

The Problem: Metric Bolt Pattern
OK, having a metric wheel bolt pattern isn’t exactly a problem, but it’s worth noting. This means you should double-check that the guy selling 8-lug Ford wheels online are actually 8-on-170, not 8-on-6½. To date, only ¾- and 1-ton 8-lug Ford Super Dutys use an 8-on-170 bolt pattern.

The Fix: 8-on-170 Wheels
Simply make sure that you are purchasing 8-on-170 wheels. Pre-Super Duty era ¾- and 1-ton trucks had an 8-on-6½-inch wheel bolt pattern, just like Chevy and Dodge (now Ram).