Is The Maxxforce 7 Diesel Engine A Piece of Junk? (Problems)

We all like to think that the products and technology we buy will be fantastic, but alas – there are always duds. There are always products that aren’t quite going to hit the mark.

You may think a particular product may be a good upgrade but this isn’t always the case – you can simply analyze Microsoft XP and Windows 7 to show you that. 

Everything You Need To Know About The Maxxforce 7 Diesel Engine, Including Problems

Today, we’re going to cover the Maxxforce 7 Diesel Engine. Is this product any good? Ultimately, there are a lot of differing opinions about it.

There are many people that believe that it’s not all that awful, and there are understandable reasons why the engine just didn’t work out as the engineers intended. Many other people aren’t quite as nice about it and will give you a long list of the various things wrong with it.

If you want to get clued up on this particular engine, all you need to do is keep reading. We will tell you everything you need to know about this engine so you can work out what you think. It’s worth noting, however, that this engine is now no longer available. 

The Maxxforce Engine – Basics

The intention was to make an incredible engine for trucking that would mean that there would be more efficiency and power in trucks for companies so that their operations could improve. It was a V8 engine and there was a lot of equipment carried next to it.

Likewise, the engine also has a remote mounted air compressor, and there were other components that meant it was quite challenging to work on this engine and to actually use it. 

Unfortunately, the engine wasn’t as good as the manufacturer intended it to be. There were issues with it from the very start, though there were a few customers that were pleased with the product they got.

The problems generally tend to lie in the EGR engine used by Navistar – this is the exhaust gas recirculation only engine. There were certainly options out there for better engines than this.

They ended up switching to using a Cummins selective catalyst reduction (SCR) technology later on but this was after some pretty big legal troubles where the EPA said they would fine them a hefty amount of cash for every engine they managed to sell.

Sadly this ECR was not the only problem either. In addition to the ECR, the overall engine was ill suited to the trucks and companies that it was designed for. Many mechanics found issues with the engine too.

It’s only natural that the engineers that worked on the design thought they were onto a winner. Unfortunately, the execution of the engine didn’t quite work out as planned, and what was really made was a poor product that was borderline unusable for many trucks.

There have been a wide variety of complaints about this product and the parts were prone to failing soon after the product launched. It would be an understatement to say that many people were unhappy. 

History Of The Maxxforce Engine

Surprisingly, there was actually a good concept behind the Maxxforce engine. The manufacturer wanted to make engines right from their own premises so they had a bunch of them available and ready to use.

This makes sense from a business perspective – for International, it would simply make more sense to have their own supply of engines rather than being left in the hands of another manufacturer that could end up providing them with faulty products.

It would, in theory, save them a lot of money and extra effort.

In addition to this, if anything was to come back with issues thanks to a faulty engine, the company would lose a lot of profits. The hope was ultimately that the new engine that they made in house would help them to avoid many of these issues.

This was sadly not the case when it came to the Maxxforce engine.

The engine was initially produced during 2003. It is believed that the engine was discontinued in 2012, though there are some people that claim that it wasn’t taken off the market until 2016.

From around 2003 to 2010, it was mainly Ford that would use these engines, though eventually they would also begin to use engines that they had made themselves in their warehouses.

The specifications of the Maxxforce 7 seemed great in practice, with 350 hp at 3000 revs per minute, and a 650 ft-lb torque when you would hit 2000 revs per minute. Sometimes the horsepower was even lower in other versions of the engine too, which was pretty great. 

Eventually the cylinder block ended up being updated, with graphite iron being made in order to make the block even stronger. Unfortunately, many of the issues in the engine did not go away – they still kept coming up.

The Manufacturer

Maxxforce Engines come from a manufacturer known as International Truck and Engine, but this company is part of Navistar International.

The trucks and motors originally made by International Truck and Engine were known for being high quality, though this was before the company was purchased by Navistar. 

The company ended up facing a lot of problems thanks to the Maxxforce 7, losing millions in profits and it had to deal with numerous lawsuits which ended up costing even more money.

As long as these engines were installed in different vehicles, the company was hit time and time again with more lawsuits. 

Eventually the company was threatened by the EPA, which made them alter the engine’s design. They ended up replacing the motor with one made by a competitor.

If you notice that your Navistar or International made vehicle has a Cummins motor, then you can be sure that that motor in question was not manufactured by Navistar. 

It seems illogical looking back that the company ever thought that the engine in question was actually a good idea. Even from the beginning the design was full of all sorts of problems.

The emission system that was chosen was wrong, and this is a huge reason why there are so many issues. All that happened was that the company had a plethora of problems and in the end they had to buy a different motor from a competitor. 

The company had to work hard in order to get through this particular embarrassment. A lot of work had to go into rectifying the issue and building up their profits again. Good changes did end up being made though, and their profits went up once more.

Release Date Of The Maxxforce Engine

The very first Maxxforce engine was made in 2003. It would have been in the research stage for a while, but we hazard a guess that its time in that phase of development was not nearly as long as it should have been.

This may seem like a bold statement, but it’s certainly one that many customers would be inclined to agree with.

It’s possible that the company released newer versions of the Maxxforce 7 later down the line, and these were likely to have been released from 2010 to 2016.

The company was still incapable of fixing many of the underlying issues with the motor series though, so they just got scrapped later on.

Every single version of this engine series caused issues for the company, with lawsuits coming at them from every angle. From around 2014 the N9 and N10 ended up replacing the Maxxforce engines.

The name change didn’t help them much though, since some people still say that the same problems exist because the motors are the same as the ones in the Maxxforce engines.

The newer engines would use a Cummings SCR system instead though rather than the original ECR system made by Navistar.

Unsurprisingly, many customers were happy that the Maxxforce engines basically ceased to exist, since they just caused problems and there seemed to be no benefits to them. This goes both for customers and for the actual company.

Discontinuation Of Maxxforce Engines

Discontinuation Of Maxxforce Engines

Maxxforce engines have since been discontinued based on information that we have found online. The thing is, there doesn’t seem to be any solid answer about when exactly they stopped being made.

Some sites will say it was discontinued in 2012, some in 2014 and some in 2016. As such, it’s hard to say when exactly they stopped appearing on the market. 

The replacement products were called the N9 and the N10 models, though there are many reviewers that say that they are exactly the same as the original Maxxforce engines. The only difference is that the emissions system was different.

People were happy to see that the product was discontinued, since it would probably take an entire lifetime to read every single complaint ever made about this engine. There are very few people that actually say anything good about this particular product.

There are some good engines in circulation from Navistar, of course. Some people did say that their version of the Maxxforce engine worked just fine.

Others have said good things but have also stated that overall they were unhappy and would not wish to use another vehicle with one of these engines. 

It has been said that the EPA ended up fining Navistar thanks to the sheer amount of emissions produced by the engine, and this is the final thing that forced the company to stop making them.

The product was simply incapable of meeting emission standards, which was a massive red flag. 

Maxxforce Lawsuit

You probably won’t be surprised to learn that the company ended up getting into a lot of lawsuits thanks to the Maxxforce 7. For instance, 3 trucking companies were represented by a lawyer and 3 separate lawsuits were filed.

The dates of the lawsuits are not listed, though you can find more information about this online and it’s on a web page copyrighted in 2021.

There are also an additional 6 companies that filed lawsuits too. This engine unfortunately seems to have gained the reputation for being the one with the most lawsuits in history. There was also a $135 million class action lawsuit too, and this was only recently fully pai up.

This settlement allowed the winners to get a payout worth $3500 or a rebate worth $10,000 on a completely new truck. 

Thanks to the lawsuit, there was also a $15,000 reimbursement program started and additionally, they have also managed to lose more than $700 million in research and developing new costs.

They have had to buy back trucks from customers that were not happy and then needed to resell them too. All in all, they lost around $1 billion dollars thanks to the problems with this engine. 

The engine has caused nothing but financial issues for this company, so it’s only natural that they should want to pretend that it never existed.

It’s not just the financial issues either – there are some customers that will be hesitant to ever go back to using this company’s engines due to what happened with the Maxxforce 7 products. The reputation has been damaged.

How To Tell If You Have A Maxxforce Engine

So how do you know if you have a Maxxforce engine? The very first thing that you should do is look at the engine and check to see if you can find the serial number. It will be printed on some part of the engine.

You will then see a list that will tell you the engine that the serial number was part of.

The engine’s name should be listed either in the service manual or underneath the vehicle’s hood. You will also see a few of the specifications. Likewise, you may also work out which engine it is based on the emissions technology that’s used in it.

If you can see that there is an ERC from Navistar then this is a good indication that this is one of the earliest editions of the Maxxforce 7, rather than the newer versions with new Cummins SRC motors. These later models were issued from around 2012 to 2014.

You can also work out what engine it is by looking at the vehicle model listed underneath the hood. SOme of the following vehicles issued between 2008 and 2013 are likely to have Maxxforce Engines:

  • International Prostar and Lonestar – heavy duty haul trucks
  • International Transtar
  • International Paystar and Workstar
  • International Loadstar

All of these are Department of Transportation trucks, class 7 and 8. These are some of the most powerful trucks that you could encounter on the road. These engines are sometimes present in Ford trucks as they have been used by the company in the past.

Just How Bad Are These Engines?

If you look at the sheer number of complaints that the company has received, alongside the money loss, you would not be surprised to learn that the motor was pretty horrendous. There is a laundry list of problems for this engine.

For instance, the engine would sometimes be prone to suddenly shutting down, which could result in dangerous situations for drivers on the road.

In addition to that sometimes the exhaust and coolant fumes would make their way inside of the truck which could be poisonous for the driver if inhaled. 

There are some mechanics that have said it’s necessary to replace the engine after 150,000 miles of using it, and in most cases it’s not actually worth the energy to  attempt to rebuild it. Many people who had RVs with these engines inside were not happy to say the least.

Other reviewers have said to steer far away from this engine, and don’t ever even attempt to use it. This is the general viewpoint of most people who have used this engine.

There are some users that have said that the older versions of the motor were where the problem lay, but many others claim that all of the engines are problematic. They say that every single Maxxforce engine that was in circulation was problematic.

It wasn’t just big rigs that experienced the issues with the Maxxforce 7 either. There were problems experienced by school buses where the high pressure fuel pumps were lost, the engine oil was diluted and the oil pressure was lost. There were many more issues beyond this too.

Is The Maxxforce 7 Total Garbage?

Is The Maxxforce 7 Total Garbage?

Surprisingly, there are people out there that believe the Maxxforce 7 isn’t a half bad engine. Some people are actually happy with it. We believe these people are likely the ones that managed to get a rare decent unit.

It’s important to consider these people when making a review, though the vast majority of the people that have used these units are not satisfied. 

Many of these people most likely did not need to pay a lot of money to repair the engine if it did have problems. They often say that they didn’t have problems with the motor.

With that in mind, it seems feasible that there were at least a few of these engines out there that were not a pile of junk. We have just mentioned a very long list of problems with this engine though, and there are also many more problems with it that we haven’t even mentioned.

A couple of decent stories about an engine doesn’t mean much to many people when you look at the bigger picture in this scenario.

We’re talking about a company losing billions, a previously stellar reputation and a large portion of market share all because they messed up on an engine. It’s hard to overcome a situation such as this.

So, what’s the verdict? Based on the opinions of a large majority of people, the motor was total garbage.

People would be spending a fortune on making repairs to the engine, and yet Navistar still didn’t do anything to update the poor emission system until the product was almost discontinued.

Based on all of this, it’s hard to call the Maxxforce 7 anything other than a very poor quality engine.

Why Are These Engines So Terrible? 

It is difficult to actually pinpoint one specific reason why these engines are so bad, because there are just so many things wrong with them. There are two particular things that are worth pointing out, however.

The design as a whole is largely at fault. The engine had an overly complicated design with far too many devices, hoses and other things included. They were all joined together in a bizarre fashion, making the engine a bit of a mess even just to look at.

It took a lot of effort to even assemble the engine, without considering anything else.

Thanks to this, if a mechanic had to look at the engine then they’d have a challenging time doing so since they’d have so much trouble taking out the additional parts. This meant that repairs would cost a lot of money and take hours longer than necessary.

The other issue is the emission technology. It was very poor in quality and didn’t really work as it should have. The design was terrible and it didn’t work very well.

It says quite a lot about the quality of the motor when you consider the fact that Navistar were forced to change it by the EPA. They had to use a motor made by a competitor instead. It’s a pretty poorly made product, and we only wish that these were the only problems with it.

Is It Possible To Fix Maxxforce Engines?

Sadly, many resorts claim that it is not actually possible to fix Maxxforce engines. The company ended up changing the emission system technology and even that didn’t fix the issue.

There were various parts in the engine that would be prone to breaking down, and the oil system would dilute pretty often. This caused a lot of problems on its own. The system was too overcrowded and complicated, and this caused issues that simply weren’t fizable.

Most mechanics would tell you that fixing this engine is a complete waste of money, so you already know that the motor is pretty awful. Most mechanics would tell you to simply scrap the whole engine instead of attempting to repair it.

The coolant design was very flawed too. The fumes would go inside of the vehicle when you tried to fill the coolant, and you would also need to refill it right from the bottom otherwise air pockets would be created inside of the engine. 

Problems With The Maxxforce Engine

If you have been paying attention so far then you will notice that there are a lot of problems that come as a package deal with this engine. The emission system was bad, the coolant system was bad and there are so many more issues.

Only the emissions system was eventually rectified, and even then the engine did not work as it should. With so many mechanical problems and potential safety risks coming with this engine, you would be better off leaving it alone.


You may not be particularly happy to learn that you have a Maxxforce engine after reading this article. Not everyone experiences the same issues, but for the most part it’s very problematic.

If you have one of these engines, you may be better off cutting your losses and trying to get a new one instead.

Madeline Cooper