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24/7 Diesel Repair
Hawkeye Diesel Repair diagnoses and repairs diesel engines across the Dallas-Fort Worth metroplex from our shop in Mansfield, TX, and through our mobile diesel repair fleet. We work on Cummins, Detroit, PACCAR, Caterpillar, and International engines 24 hours a day, 365 days a year.
Engine failures cost you money every hour your truck sits idle. These are the symptoms DFW drivers call us about most often.
If your truck shows any of these signs, call us or schedule service through our contact page. We respond to calls across Dallas, Fort Worth, Arlington, Mansfield, and surrounding ZIP codes including 76063, 75051, 76011, 76104, and 75201.
Hawkeye Diesel Repair works on every major diesel engine platform running through North Texas. Our technicians carry OEM diagnostic tools for each brand and train on current service bulletins.
The Cummins X15 is the most common Class 8 engine on DFW highways. The X15 Efficiency Series produces 400 to 500 hp and 1,450 to 1,850 lb-ft of torque. The X15 Performance Series produces 485 to 605 hp and up to 2,050 lb-ft of torque. The Performance Series runs a 17:1 compression ratio, while the Efficiency Series uses a higher ratio for fuel economy. Both series feature a VGT turbocharger and XPI common rail fuel system.
We handle Cummins X15 repairs including injector replacement, ECM recalibration, turbo actuator failures, EGR cooler leaks, and aftertreatment system faults. We also service the ISX15, ISB 6.7, and ISL 8.9 platforms.
The Detroit DD15 is a 14.8-liter inline 6-cylinder engine with an 18.5:1 compression ratio. It produces 400 to 560 hp and 1,550 to 1,850 lb-ft of torque. The DD15 uses an Amplified Common Rail System (ACRS) and an asymmetric turbocharger paired with DDEC electronics.
Common DD15 repairs we perform include ACRS injector failures, turbo bearing wear, oil cooler leaks, DPF differential pressure sensor faults, and DDEC software updates. We also service the DD13 and DD16 platforms.
The PACCAR MX-13 is a 12.9-liter engine that produces up to 510 hp and 1,850 lb-ft of torque. It uses a common rail fuel system operating at up to 2,500 bar injection pressure. The MX-13 runs compression ratios between 16.5:1 and 18.5:1 depending on the model year and emissions tier. This engine is standard in Kenworth and Peterbilt trucks.
We repair MX-13 fuel injectors, EGR valves, VGT turbochargers, oil pump failures, and aftertreatment system issues. We also work on the MX-11 platform.
We also service Caterpillar C13 and C15 engines, International A26 engines, and Hino diesel platforms. If it runs on diesel and operates in the DFW area, our technicians can diagnose and repair it.
Fault codes trigger derates, warning lights, and shutdowns. Our technicians use OEM-level diagnostic tools including Cummins INSITE, Detroit Diesel Diagnostic Link (DDDL), PACCAR ESA, and Nexiq USB-Link adapters to read, diagnose, and clear these codes.
SPN 5246 indicates a problem with the diesel exhaust fluid (DEF) system on engines equipped with selective catalytic reduction (SCR). When this code goes active, the ECM limits vehicle speed to 5 mph. Common causes include a failing DEF pump, clogged DEF lines, contaminated DEF fluid, a faulty DEF dosing valve, or a bad NOx sensor. Clearing this code requires a dealer-level scan tool and a root cause fix. We diagnose and resolve SPN 5246 on Cummins, Detroit, PACCAR, and International engines.
SPN 3719 means the diesel particulate filter (DPF) soot level is above the normal operating range. The truck needs a parked regeneration within minutes of this code going active. If the regen fails, the ECM will derate or shut down the engine. Root causes include a stuck DPF differential pressure sensor, plugged pressure sensor tubes, faulty exhaust gas temperature sensors, failing injectors causing excess soot, or a DPF loaded with ash beyond its service interval. We perform forced regenerations, diagnose root causes, and service or replace DPF assemblies.
If your truck is in a derate on I-35, I-20, or anywhere in the DFW metroplex, call us at (972) 945-3183. Our mobile diesel mechanics can reach you and clear codes on-site.
Hawkeye Diesel Repair offers full-service diesel engine work from our Mansfield, TX shop and through our mobile units across Dallas-Fort Worth.
We connect to your engine’s electronic control module (ECM) with OEM software to pull active and inactive fault codes, read freeze frame data, check sensor readings, and verify calibration versions. When your ECM needs a recalibration or software update, we flash it on-site. This applies to Cummins INSITE calibrations, DDEC reflashes, and PACCAR ESA parameter changes.
Diesel fuel systems operate at extreme pressures. The Cummins XPI system and PACCAR common rail system inject fuel at up to 2,500 bar. The Detroit ACRS system uses amplified pressure for precise atomization. We replace leaking or failed fuel injectors, high-pressure fuel pumps, fuel rails, and fuel filters. We also diagnose low rail pressure codes and fuel contamination issues.
Turbo failures cause power loss, black smoke, and high exhaust gas temperatures. We repair and replace variable geometry turbochargers (VGT) on Cummins, wastegated and non-wastegated turbos on Detroit engines, and VGT assemblies on PACCAR platforms. We check turbo shaft play, actuator function, boost pressure, and wastegate operation.
The aftertreatment system includes the diesel oxidation catalyst (DOC), diesel particulate filter (DPF), selective catalytic reduction (SCR) catalyst, DEF dosing valve, DEF pump, NOx sensors, and exhaust gas temperature sensors. We perform forced regenerations, DPF cleaning, DPF replacement, DEF system repairs, and NOx sensor replacement. Normal DPF ash cleaning intervals range from 300,000 to 400,000 miles depending on the engine and duty cycle.
Overheating damages head gaskets, warps cylinder heads, and cracks blocks. We repair and replace water pumps, thermostats, radiators, charge air coolers, EGR coolers, and coolant hoses. We pressure test the system to find leaks and check coolant concentration levels.
When an engine reaches the end of its service life or suffers a major failure, we perform in-frame and out-of-frame overhauls. This includes replacing pistons, liners, bearings, gaskets, seals, and rings to OEM torque specifications. We measure crankshaft journals, check cylinder bore dimensions, and verify clearances before reassembly.
Diesel engines depend on sensors, wiring harnesses, ECMs, and actuators. We diagnose and repair open circuits, short circuits, corroded connectors, failed sensors, and communication faults between modules. We use multimeters, oscilloscopes, and breakout boxes alongside OEM scan tools.
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Our Mansfield, TX shop sits at the center of the DFW metroplex. Our mobile units cover a radius of 1 to 1.5 hours from our shop. We regularly service trucks in these areas:
View our full service area map for coverage details.
Diesel engine repair covers the diagnosis, maintenance, and fix of mechanical, fuel, electrical, and emissions problems in compression-ignition engines. Diesel engines power Class 5 through Class 8 trucks, buses, construction equipment, generators, and marine vessels. These engines compress air at ratios between 16:1 and 21:1, which ignites fuel without a spark plug.
Repair work ranges from replacing fuel injectors and glow plugs to rebuilding entire long blocks. It also covers aftertreatment systems, turbochargers, cooling systems, and electronic controls. Diesel technicians use OEM scan tools to read fault codes from the engine control module, test sensors, command actuator tests, and recalibrate software.
Routine maintenance prevents breakdowns. Oil changes, fuel filter replacements, coolant checks, valve lash adjustments, and DPF ash cleaning keep engines running within spec. The Cummins X15 supports oil drain intervals up to 50,000 miles for long-haul applications. The Detroit DD15 supports oil change intervals up to 50,000 miles in long-haul duty cycles. Skipping maintenance leads to premature failures, unplanned downtime, and expensive repairs.
When your vehicle breaks down, it may be challenging to find a company who can be there when you need it.
We repair Cummins (X15, ISX, ISB, ISL), Detroit (DD13, DD15, DD16), PACCAR (MX-13, MX-11), Caterpillar (C13, C15), International (A26), and Hino engines. If it runs on diesel, we can fix it.
Watch for hard starts, black or white smoke, loss of power, rough idle, high coolant temperature, low oil pressure, check engine lights, or DPF warning lamps. Strange noises like knocking or turbo whine also signal a problem. Call us at (972) 945-3183 if you notice any of these.
Yes. Our mobile diesel mechanics carry OEM-level scan tools. We diagnose the root cause, make the repair, and clear the codes at your location. We handle SPN 5246 derates, SPN 3719 DPF faults, and other aftertreatment codes on the road.
Response time depends on your location and our current call volume. We cover the DFW area from our Mansfield shop and aim to reach most locations within 60 to 90 minutes.
Yes. We service owner-operators with a single diesel truck and fleet operators running multiple units. We offer the same diagnostic depth and repair quality for every customer.
An in-frame overhaul replaces pistons, liners, rings, bearings, gaskets, and seals without removing the engine from the truck. An out-of-frame overhaul removes the engine completely for a full teardown, inspection, machining, and reassembly. Both follow OEM torque specs and clearance measurements.
Yes. We perform oil changes, fuel filter replacements, coolant system checks, valve lash adjustments, DPF ash cleaning, and full engine inspections. Regular maintenance extends engine life and prevents roadside breakdowns.
Call Hawkeye Diesel Repair or visit our contact page to schedule service. We offer diesel engine repair in Dallas-Fort Worth, TX from our Mansfield shop and through our mobile service fleet, 24 hours a day, 7 days a week.
Hawkeye Diesel Repair is a mobile diesel mechanic serving the Dallas- Fort Worth metroplex. We get diesel drivers back on the road quickly and safely.