— It’s no secret that Navistar International had its share of EGR-related failures as it attempted to meet EPA10 emissions standards without the use of SCR exhaust aftertreatment. The company very candidly addressed the issue at its Analyst Day earlier this week, and offered a full explanation of the fix it has implemented. Tim Shick, vice-president of sales support with Navistar, said most of the problems could be traced to the MaxxForce engine’s turbo air control valve, which connects directly to the engine’s electronic control module (ECM). The ECM, very importantly, would dictate via that connection how much fresh air should be supplied to the engine and for how long, as well as how much hot exhaust should be supplied and for how long, to effectively reduce emissions.

1. Maxxforce 10 Oil Capacity

However, constant vibration and wind underneath the hood would cause the connection to become loose. “When this began to fail, it didn’t become totally dislodged,” Shick explained. “The truck went down the road and the connector moved around due to vibration and wind under the hood and through a process called ‘fretting’ would wear these pins down to the point where it would connect intermittently.” The intermittent connection would cause the device to “overfuel” the engine with sooty exhaust, which first went to the EGR valve. Exacerbating the situation, the shaft on the EGR valve was prone to failure, allowing in a free-flow of soot-saturated exhaust. “What usually happens is you get an open flow of exhaust coming in at will, which is full of soot, because the engine is not combusting all the fuel completely and it goes into the EGR coolers,” Shick explained.

Next thing you know, the exhaust manifold, valve and coolers inside the EGR housing are filled with soot. Fuel economy deteriorates, a dashboard light comes on and the truck needs to be taken out of service.

This was problematic with engines produced in 2010 through 2012. However, by 2013 Navistar had identified the problem and taken steps to address it, Shick explained. For starters, it hardwired the connection from the turbo air control valve to the ECM so that it could no longer shake free and lose its connection as a result of over-the-road vibrations.

It also made the EGR valve shaft 30% larger and less susceptible to sticking. Navistar also removed some sharp edges from within the system that were causing premature fatiguing and cracking of components. It also redesigned the EGR cooler, providing more room for exhaust gases to flow. Navistar says the improvements have dramatically reduced warranty claims. It now updates used trucks taken in through its Diamond Renewed used truck reconditioning program to implement the improved components. International MaxxForce engines built in 2013 and after will already come with the fix.

An International dealer can determine whether pre-2013 engines have been updated with the improved parts. Navistar is so confident with the fix, it offers a one-year, 100,000-mile warranty on used trucks that have been reconditioned through its Diamond Renewed program. All of the newer trucks are not very relible, at least before we could get it to the garage to repair it now it just quits. Has anyone done a study to figure out the true cost of EGR/DPF/def related to all the repair costs? I wonder if we worked it out we would not figure out that all the repairs and making of replacement parts is MORE damaging to the envoirment than the extra emissions equetment? My old trucks seemed to get the same fuel mileage 20 years ago maybe an improvement on old engines would produce a net benefit to the envoirment?

The theory of Exhaust Gas Recirculation was to combat against in adequate engineering of past generation combustion systems with UNmonitored emissions. The modern other fuel technology has adapted exhaust monitoring systems that continue to adjust information to fuel systems so that they achieve optimal combustion in multinational operating conditions. The large hate organizations against transportation professionals and the associated equipment is a continuous process that has become the economic depression for many in the USA.

Secondary Exhaust Treatment systems are a continued presence that adds weight to modernization of transportation technology and reliability. The soot created by and an inappropriately adjusted engine is entertainment yet gasoline bio or otherwise exhaust monitoring communicates back to a central fuel injection system to solve this problem decades ago this similar type of technology should be adequate with new models of structuring combustion chambers in diesel technology with out need for secondary techniques or excessive recirculated emissions one would think with all this modern digital technology and connectivity. Just went through the EGR issue with our International ambulance.

It is a 2010 with a Maxxforce engine. Unit kept stalling out or not wanting to go when you hit the accelerator.

I had to drill 5/8 holes into 30MPA concrete to insert loxins in.

Exhaust temp light coming on all the time and really bad exhaust smell and white smoke from the pipe. I had it in the shop and they found the EGR cooler bad and pipe leading to the cooler full of black soot that they could not remove. Had to have the whole system replaced. Not a cheap repair. The truck has been a nightmare from day one. Had a second truck with the same motor.

No longer part of our fleet. I’ve got a 2015 ProStar Eagle with a Maxx Force 13 with Cummins SCR. It was 1 of 48 that were used as a test fleet by Swift for 50,000 miles. It has the larger volume EGR Valves and the improved oil filter system introduced on the 2014 Maxx Force 13. It also has a much larger radiator and coolant capacity that was specified by Swift. It has a 12 speed Ultrashift automated transmission.

It also has a TK APU. Maxx Force engines idle at much higher temp than others and that’s when the most soot is made clogging the DPF. Just the words Maxx Force made this truck 25% cheaper than other brands with the same features and miles. I bought this from International in Phoenix for $91K with 52K on the odometer. I run a Harbor Freight tools loop from Moreno Valley, CA to San Antonio, TX to Oklahoma City, OK and back to Moreno Valley. No Giant mountains, but Texas Hill Country & a lot of big hills on I-40 in NM & AZ. My average starting weight is 39,000 lbs, returning to California with about 14,000lbs.

I limited my cruise control to 65mph and foot throttle at 68. The truck now has 322K, my running 52 week fuel average is 9.3MPG. I guess putting 55-70% less hot dirty air into the combustion chamber works and lowers idle temps greatly. I have not had a break down or major repair, just normal services and ECM updates(2). BTW the ECM looks the same but I was told at International Phoenix that it’s mostly a Cummins on the inside. I replaced the wimpy Mexican brand X shocks with Gabriel Gas SLC shocks and the ride is very comfortable even on concrete slab.

I have replaced the Left Front Dim bulb 5 times all other lights are original. I drove a Maxxforce 7 diesel 8 cyl in a class 7 like full sized school bus. One hour north of Toronto on mostly rural but some urban suburb low speed streets.

Maxxforce 10 Oil Capacity

The buses were a bear all winter long needing multiple parked regeneration. One in particular went back to local Navistar dealership for new parts and sensors three times.

The companies warranty rights run out after 100,000 kilometers. The cost to fix a DPF beyond warranty are astronomical. I also did routine crankcase oil level checks to see how much higher it had gone. Other drivers ignored that issue and stressed the motors. In one case a broken piston. You also gotta wonder what viscosity crankcase oil is when it is cut 25% through bypassed diesel contained in it.

Yes quite the star if you buy Navistar! There is a fix, for this it’s an add on for a hydrogen fuel cell, stops regen system because all fuel is converted to 80% octane burns 100% of diesel so no soot adds horsepower and mileage. Can be purchased on line and installed by you or mechanic have been using four years works on any rig. Although takes a few days/weeks to clean-up any gunk, my regen was running every day, after hydrogen add-on the fuel was so pure it may activate once every 3-4 weeks. No changes made other than add-on completely legal.

It takes a while to search it out, since the website changes from time to time. They have had a lot of resistance from the powers that be. Sorry I cannot recall website at this point as has been 4 years, but I am sure they are out there. FYI I’ve been driving professionally since 1978. I just purchased 3 – 2012 Prostars Plus Daycabs with the Maxxforce Engines and 10 Speed Ultrashift Auto Transmissions for $16,500 each a month ago. The trucks had 200,000 miles, 400,000 miles and 500,00 miles. It just seemed like a crazy low price A Lot of Candy for a Dime!

They were Fleet trucks from Dallas. The all looked Brand New!

The first thing that I noticed was how Quiet they were! They are getting around 6.5 MPG.

They run 7 days a week, about 500 miles/day. I am in South Florida, so the terrain is very flat. I use them to pull Milk Tankers, drop & hook, so there is very little idling (other than in traffic in Miami). So Far ZERO Problems! I am thinking about doing the EGR Delete/DPF Bypass. Anyone do this on a Maxxforce yet?

I can count on one hand how many times I’ve read an entire operation and maintenance manual. These manuals come with a new vehicle and I would guess they don’t get much use unless a specific question arises.

We received new International buses recently powered with Maxxforce 7 diesel engines and since they are a model I am not familiar with the best resource to start with is the operation and maintenance manual. Since I’m reading the manual front to back I thought it would be interesting to share this information. You would be surprised how much information there is in these manuals.

There’s much more than how to check the oil or how much coolant capacity the engine has. On the contrary I learned some valid facts about the Maxxforce 7 that will help me with maintenance care and scheduling.