HIGH-MILEAGE ISX TEARDOWN

DURABILITY.EVERY PROOF.

TM

While Cummins 2002 engines have yet to reach theirfull life expectancy, Cummins has inspected multiplehigh-mileage cooled-EGR engines. A teardown of thehighest-mileage ISX engine, with nearly 600,000 miles(965,607 km), proves that the Cummins engine designwith its cooled-EGR subsystem not only meetsdependability and durability goals, but is well on its wayto surpassing the previous standard established by the“bulletproof” Cummins N14. This brochure containsunretouched photography and DVD footage showingkey engine components from the teardown.

High Mileage. Low Wear.In early 2005 Cummins engineers did a completeteardown on a high-mileage ISX engine owned byUSA Truck, based out of Arkansas. This truck wasused in a team operation logging over 200,000 miles(321,869 km) per year on a dedicated route.

Engine Model: ISX SmartTorque

Engine Serial Number: 79005693

Mileage: 581,954 miles (936,564 km)

Oil Change Interval: 30,000 miles (48,000 km)

using CI-4 oil

Owner: USA Truck

Key Indicators Of Durability.Cummins carefully analyzed all technologies anddetermined that cooled EGR is the right choice forthe best performance, fuel economy, reliability anddurability. Our ISX engine with cooled EGR is theindustry leader in every aspect.

Engine durability is defined by the engine overhaulpoint – the life-to-overhaul.

The need for an engine overhaul is reached when anengine has excessive engine wear, oil consumption orblowby. To determine this point, you need to look atboth the base engine components and the combustionsystem wear.

The Proof Is In The Parts.Following complete disassembly of this engine,individual components were scrutinized for scuffing,scratches, unusual wear patterns or discoloration –anything that could potentially affect engineperformance or durability down the road. Not a singlecomponent showed anything other than normal andexpected wear. This engine could be reassembledand run for many, many more miles.

EVERY PROOF. DURABILITY.

Base Engine Components.The main and rod bearings are built in three layers withdifferent metals. When the outer layer wears through,the second layer of nickel starts to show. At this point,the bearings are designed to be at 50% of their life.On the main bearing of the ISX teardown engine, thenickel was just beginning to show at the 600,000-mile(965,607 km) mark, so you could reasonably doublethe mileage as a projected life-to-overhaul, and the rodbearings were not even to this point yet!

Upper And Lower Main Bearings.Show normal wear with minorabrasions that would not affect theoil film thickness.

Upper And Lower RodBearings. Taken from the#5 cylinder, they show onlynormal wear with twominor scratches on thelower rod bearing.

Connecting Rod. The upper pin bushing bore iscritical because it takes 2800-psi cylinder pressure.

Rods in the ’02 ISX engine havean oil drilling that feeds oil up tothe bushings, so they are inexcellent condition.

Combustion Chamber Components.The cylinder liner, piston and piston rings have tofunction with absolute precision for an engine to functionefficiently and durably. Any contamination issues willbe quickly evident on these parts with extremelytight tolerances.

The second ring is designed to show how much wearis taking place. It functions like an ice scraper, with a2-degree taper keeping oil out of the combustionchamber. One of the things the service techniciancalculates is how much of the angled face is wornaway to determine how long until the engine will needan overhaul. On this engine the ring was just starting toshow wear at the 20%-25% mark, indicating that thispiston ring set could go another 75%-80% more milesbefore needing an overhaul.

Piston Rings. The chrome-plated top ring stillmaintains its radius with minimal wear. Good formany additional miles. Tapered second ring showsonly 20% wear on an engine that already has closeto 600,000 miles (965,607 km). Oil ring in nearperfect condition.

Monotherm® Piston. No variance in color across thecrown indicates uniform combustion for high efficiencyand clean operation. The lack of carbon packing on theback of the top ring or on the second land betweenthe top and second rings indicates that the top ringis functioning properly, sealing combustion gasesinside the cylinder. The carbon above the top ring isperfectly normal for a high-mileage engine.

Cylinder Liner. Mid-stop cylinder design clamps linerfirmly in place. No cavitation evident on exterior.Cross-hatch patterns from plateau honing still visible oninterior. Induction-hardened liner shows no sign of borepolishing or unusual wear.

EGR System Components.Cummins cooled-EGR subsystem is designed tohandle hot exhaust gas with an advanced design andmaterials. Our experts are pleased with itsexceptional performance.

EGR Valve. The EGR valve shownhas been in operation for309,000 miles (497,288 km)and shows no degradation orheat distortion.

EGR Cooler. Passages arefully open on the inlet side. A thinlayer of carbon deposits equal to exhaustmanifold, with no loss in cooler efficiency,

was observed.

Intake Manifold. A normal andexpected amount of carbon was present, similar to theexhaust manifold. The extra corrosion-inhibiting paint isperforming well, with no aluminum corrosion evident.

Every MPG.While assessing the long-term durability of this enginewas the primary reason for the teardown, perfomancedata captured from the ECM using PowerSpec clearlyillustrates the value of a “fuel economy” spec andproves that Cummins is the fuel economy leader.The ISX engine in this truck featured a SmartTorquerating configured with a 10-speed direct transmissionand 2.64 axle ratio. Load-Based Speed Control wasenabled, along with Gear-Down Protection. Idle speedwas locked in at 650 rpm,and vehicle speed was setfor 63 mph. This truck wasrun almost continuously,resulting in a top gearpercentage greater than95% and idle time at 12%.

The result: This engine wasdelivering 7.6 mpg overall,and 7.8 mpg on the road.

Every Step. Ahead.The durability and dependability of our ISX enginesare the result of years of planning, beginning back in1998 with the introduction of the ISX engine with ahigh-pressure fuel injection system and dual overheadcamshafts. We anticipated and planned our enginearchitecture to run cleanly, efficiently and with excellentdurability with the addition of the cooled-EGR subsystemin 2002. And we will continue to use this same enginearchitecture through 2007 and beyond. Cumminscustomers can have every confidence, knowingthat they are getting an engine that will deliver theperformance they expect. Every mile, for milesdown the road.

Seeing Is Believing.The DVD included with this brochure shows the engineremoval and disassembly process, as well as close-upsof critical components from crankshaft to the dualoverhead camshafts to the power cylinder. It providesa more detailed look at this 2002 ISX engine with thecooled-EGR subsystem. This video footage provesbeyond question that Cummins technology providesthe kind of durability you can depend on every dayfor years to come.

Every Question. Answered.■ Service Network – Cummins engines are backed bythe strength of Cummins global network of over 5,500service locations worldwide.

■ Customer Assistance Center – For technicalassistance, service locations and product literature,call 1-800-DIESELS (1-800-343-7357).

■ Cummins E-Mail – For online assistance toCummins-related questions, click on the Contact Uslink in the header at www.everytime.cummins.com.

■ Cummins Online Registration – Register allyour Cummins engines quickly and easily atwww.everytime.cummins.com to ensure qualityparts and service for your engine.

Cummins Inc.Box 3005 Columbus, IN 47202-3005U.S.A.

Phone: 1-800-DIESELS (1-800-343-7357)Fax: 1-800-232-6393Internet: www.everytime.cummins.com

Monotherm® is a registered trademark of MAHLE, Inc.

Bulletin 4103867 Printed in U.S.A. 3/05©2005 Cummins Inc.

Cummins is a pioneer in product improvement. Thus specifications may change without notice.Illustrations may include optional equipment.