GUEST EDITORIAL
EGR cooler
We hear things like “Oh man, not again,” or
“I wish we could just do away with it altogether”
50 Fleet Maintenance | May 2018
all the time when fl eet maintenance
professionals encounter ruptured EGR coolers.
It seems a pretty safe bet that the subject of EGR
coolers and their replacement is not a happy
one when it comes to the folks who have
to directly deal with the problem.
It’s an all-too-common
situation: a failed EGR
cooler leads to replacement
part costs, plus
vehicle downtime. Aft er
replacing the EGR cooler with
a new OE unit, everything seems fi ne only
to fi nd the replacement EGR cooler fails. At
this point, sheer frustration from the “repair”
can take its toll. Th is can lead to fl eets shedding
vehicles that regularly blow through EGR
coolers, oft en before the expected service life
of said vehicle. Between parts costs, labor
costs, vehicle downtime and the unscheduled
replacement of that vehicle, the initial procurement
of the vehicle might look like a misstep.
EGR cooler failure usually results from
one of three causes. Th e most common cause
stems from thermal events. Th ermal events
refer to any situations where the EGR cooler,
for whatever reason, isn’t getting enough coolant
to prevent heat expansion inside the unit,
and the internal metal core pushes the ends
of the cooler apart, rupturing it. Less common
failures result from EGR coolers plugging up
due to carbon deposits from exhaust, or from
simple metal fatigue aft er several years of use.
To address these failures, there have been
several advances made in EGR cooler technology
in recent years. Many of these technologies
are coming from the aft ermarket. Th ere’s a
reason for this, and it’s somewhat unexpected:
OE manufacturers generally haven’t off ered
solutions for EGR cooler problems aft er a
warranty expires.
In other words, the vehicle manufacturers
generally haven’t looked backwards to engineer
solutions for old parts. In many cases,
they’ve simply used the same historical part
design as a stopgap replacement until the
part or vehicle warranty expires.
Th is leaves fl eet personnel high and dry;
it’s not legal in any state to operate a diesel
vehicle with a malfunctioning EGR system,
but solutions for some particularly troublesome
EGR coolers haven’t been available.
A notable example
In one well-known example, Ford had an issue
with EGR cooler failure problems occurring in
2003-2007 Super Duty and E-Series van diesel
engines sourced from Navistar. Th e issue
stemmed from a design fl aw in the engine oil
cooler, which would lead to thermal event situations,
sometimes causing EGR cooler failure.
A class-action lawsuit resulted, and Ford ultimately
chose to build its own diesel engine for
light trucks in 2010.
Th is was a signifi cant turn of events, traceable
in part to the shortcomings of the EGR
cooler, a part designed to do nothing more than
reroute exhaust back to the engine’s cylinders.
Private owners of these trucks were faced with
an entire generation of potentially faulty parts.
Even when EGR coolers were replaced with new
units, failures would oft en result, and damage
to other engine components could occur. Th is
large population of truck owners continued
to look for a solution, eventually turning to
the aft ermarket.
In 2009, Arizona-based Bullet Proof Diesel
developed replacement EGR and oil coolers for
the engine platform, and these were successful
in stemming the failures. Other aft ermarket
companies followed suit, and the market for
upgraded EGR coolers was created.
Expanded options
Commercial fl eets have not been immune to
the consequences of unreliable EGR coolers.
Th e conventional design of the part (fi nned
tubes that resemble a radiator) simply cannot
compensate for the core expansion that results
from a thermal event. In fact, the larger EGR
coolers found in medium duty and heavy duty
trucks are even more susceptible to damage
during thermal events, because longer cores
mean more heat expansion. Th is expansion
exerts pressure on the bulkheads of the cooler,
and a rupture could occur.
To address these concerns, Bullet Proof
Diesel released a line of commercial duty EGR
coolers with a patented core type designed to
resist expansion-related ruptures in 2017.
Known as H-Core, the exhaust tubes of these
EGR coolers are arranged in a helical pattern
that resembles a braid. Tube expansion can be
accommodated within the EGR cooler because
the tubes can broaden in a lateral direction.
Th is means the “braids” have the ability to
become larger in diameter when heated. In
laboratory tests, the potential pressure to the
ends of an H-Core-equipped cooler was only
about one-fourth of the pressure a conventional
core would exert. Th is means the EGR cooler
isn’t as susceptible to expanding to the point
of ripping itself apart during a thermal event.
Options like this now provide a viable alternative
for fl eets in need of commercial duty
EGR coolers.
Addressing EGR
cooler failures Aftermarket EGR coolers can provide a solution to OE replacement parts.
By Jeff Dahlin
CHIEF MARKETING OFFICER, BULLET PROOF DIESEL
Bullet Proof Diesel (bulletproofdiesel.com) was established in 2009 as the first company to offer upgraded
EGR coolers for the International-sourced Ford 6.0L Power Stroke engine. Additional EGR cooler designs followed
for larger applications. Bullet Proof Diesel now supplies EGR coolers to organizations such as Frito Lay,
UPS, LA County Fire and many other commercial fleets. Dahlin has been a respected voice in the transportation
industry for almost two decades. As publisher for a number of publications, such as Hot Rod, Diesel Power,
8-Lug, Off-Road, Truckin’, Car Craft and others, Dahlin directed the evolution from print properties to multimedia
enthusiast brands. Dahlin started with Bullet Proof Diesel in 2016, heading up transitional efforts to move
a significant part of the business from the enthusiast space to the commercial fleet segment.
» Buried under the intake manifold, the
Bullet Proof Diesel EGR cooler is visible on
this International VT365 diesel engine.
Image courtesy of Bullet Proof Diesel
» A Bullet Proof
Diesel H-Core
EGR cooler (left),
demonstrating
the exhaust tubes
arranged in a
helical pattern that
resembles a braid.
A conventional
EGR cooler is
on the right.
Image courtesy of
Bullet Proof Diesel
/bulletproofdiesel.com
