Purchasing a second-hand Powerstroke is one of those things that can turn out really great or really bad depending on what knowledge you have before getting into the deal. These vehicles keep their value because they are powerful, they last, and the demand remains quite high. Besides, they even have generation-specific problems that if overlooked during the purchase, can turn a decent deal into a disaster leading to significant financial loss within just a few thousand miles.
Generally, the variation between the best and the worst used Powerstroke is not mileage. It is maintenance history, what has been done already, and what the previous owner did or didn’t do when it came to known points of failure for that particular engine. A properly serviced truck with 250,000 miles can be a better purchase than a 90,000-mile truck that has been neglected.
Being equipped with the right knowledge is the key here. Understanding what to look for, what to ask, and which red flags matter more than others are the ways you get a truck that suits you instead of one that dominates you.
Know Which Generation You’re Looking At
The 7.3L Powerstroke built between 1994.5 to 2003 is the least complex engine among this group and probably the most tough one. Here is the thing though, it was the first one, so as a rule of thumb a car that old will exhibit typical problems caused by their aging. Rust, failure of accessories, tired transmissions are more likely to be issues one has to deal with than the engine itself. Basically, it is possible for a well-maintained 7.3L to run forever however finding one that is clean without a price that has been artificially raised has become more difficult with each year that passes.
The 6.0L model years 2003 to 2007 is known as the worst one, in part it deserved being the worst and in part it is the result of unfounded rumors. This engine does have a few known weak points, it is easy for the head bolts to stretch, EGR coolers may be found to have cracks, oil coolers get clogged, and the FICM fails when it’s exposed to moisture however these issues are all manageable. A 6.0L that has been studded and had the coolers replaced could be bought at a nice discount and then be a very good choice. A 6.0L that is completely stock, has high mileage and has no service records is like tossing a coin.
The 6.4L diesel engine which was available from 2008 to 2010 comes with the biggest appetite for fuel and the most problems related to emissions. Re-gen cycles dilute the oil, piston cracking occurs under certain conditions, and unfortunately, the emissions components are quite pricey when they fail. If you are going to be the owner of a 6.4L then you will have to come to terms with the fact that either you are going to be dealing with the aftereffects, or you are going to opt out of purchasing this vehicle.
Maintenance Records Tell the Real Story
First of all, odometer readings can be deceiving or at least they do not tell the whole story. A truck that has been driven 200,000 miles and still has maintenance receipts to prove it can often be a better buy than a truck that has only 100,000 miles but without any proof of maintenance. The Powerstroke engine remarkably supports owners who take their truck to schedule but owners who delay maintenance intervals or use cheap parts get punished by the engine.
Be sure to ask for the oil change records. The reason being these engines need to be changed frequently with an oil of the correct specification and the owners who change intervals are the trucks that develop problems. Short intervals with quality oil, especially on 6.0L and 6.4L engines where fuel dilution is a real issue, are more important than almost any other maintenance item.
Changes of fuel filters are important too, especially on 6.7L trucks with the CP4 injection pump. Fuel contamination will kill CP4 pumps and owners who have not kept up with the filter servicing are the ones who are faced with $10,000 failures. If there is no record of filter changes, then it is safe to assume that they have not been done and you should include that in the price.
Inspect the Known Weak Points in Person
Every Powerstroke generation comes with its own set of features to be checked, and the most common mistake people make is to walk up to a truck without having any idea of what they should be looking for, which is how they miss the problems that really matter. On any generation, always begin with the coolant and the oil. Remove the oil cap and check if there is any coolant residue or milky film. Such signs usually indicate that the oil cooler or the head gasket is leaking. Now, open the degas bottle cap and check whether there is an oily film on the coolant which in turn suggests the same problem but from another side.
With 6.0L and 6.4L trucks, the focus should be on the cold start performance. If a 6.0L model is quite reluctant to start when it is cold, then this usually means that there will be some problems with the FICM, and too much white smoke that takes a really long time to disappear would be an indication of head gasket problems. Also, don’t forget to listen to the turbo while the truck is being accelerated, and write down any strange sound or hesitation that could be a signal of a problem with the emissions components or the turbo vanes.
For 6.7L trucks, by far the most crucial point of examination is the fuel system. If the CP4 has broken down and been replaced, then be sure to ask for the papers and check whether the rest of the fuel system has been properly flushed. A CP4 failure which has not been serviced properly results in the whole fuel system getting contaminated by metal particles, and the new pump will
Understand What’s Been Modified
The condition of a modified Powerstroke may turn out to be extremely good or really terrible depending on what was done and how it was done. Properly done modifications by a recognized builder especially on a truck that has been regularly serviced generally add value as the previous owner has upgraded the vehicle with things you would have done anyway. Poorly done modifications or heavy tuning on the stock bottom end are the ways engines are destroyed.
If the vehicle has been tuned, check who did it and if it is supported. A credible tuner utilizing a calibration with the proper supporting setup is okay. A random tune of an unknown source on a high-mileage vehicle with no supporting modifications is a red flag.
For trucks being sold as off-road or competition vehicles, it’s common to find custom deletes for all Powerstroke engines, which remove emissions equipment for non-road use. If you’re buying a deleted truck, you need to understand the emissions laws where you live and where you plan to register the truck. Some states have no inspection, some have strict emissions testing, and driving a deleted truck in the wrong jurisdiction creates legal and registration problems that have nothing to do with how the truck runs.
Final Thoughts Before Writing the Check
You should always have a diesel specialist Powerstrokes inspection before buying a vehicle. A generic mechanic may overlook the things that are important to these engines, and spending two or three hundred dollars on a check-up is probably the cheapest way to protect your investment of buying a truck. A shop that knows these engines, such as Diesel Patriots, will identify problems that even a thorough road test and visual examination will not reveal.
When buying a used Powerstroke, if you do so correctly, it can be among your best working trucks. On the other hand, if you don’t buy it carefully, it may be one of the quickest ways you spend money you hadn’t planned to. Slow down and ask questions, check the records to see if the claims are true, and look over the truck keeping the problem areas in mind. The truck that is good for you will be able to handle the rest of the things that you’ve mentioned. The one that can’t is the one you don’t want anyway.
