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Mack MP7 Engine

Mack MP7 Engines For Sale

The Mack MP7 is a light-weight, 11-liter inline-six diesel engine that is capable of achieving 425 hp and as much as 1,200 lb-ft of torque. The MP7 underwent some revisions in its time in production, namely in 2010 when SCR (Selective Catalytic Regeneration) was introduced. Implemented on both the MP7 and MP8 engines, SCR technology allowed Mack to meet the EPA’s stringent 2010 NOx emissions standards.

All MP Series engines make use of intake throttles that are designed to improve heat management. They effectively increase the engine’s exhaust gas temperature (EGT) at idle and low load, which increases the efficiency of the exhaust aftertreatment system. As for weight-sensitive applications such as bulk hauling, the MP7’s lighter overall heft (compared to its competitors) pays big dividends.

Engine Applications and Uses

  • Highway Trucks
  • Heavy-Duty Vocational

Common MP7 Mack Engine Problems & Failures

Catalogued below, you’ll find some of the most commonly experienced engine problems from customers who inquire about replacing their MP7 engines. Unfortunately, some of the failures listed typically mean complete engine replacement is the only option. However, if some of these issues are caught in time, most of the engine can be salvaged.

AERA Association Member

  • Camshaft Failure
  • Connecting Rod Failure
  • Cracked Cylinder Head
  • Crankshaft Failure
  • Dropped Valves
  • Lifter/Roller Failure
  • Lack Of Oil or Oil Pressure
  • Extreme Blow By
  • Overfueling
  • Scored Pistons and Liners

Mack MP7 Engine Replacement Options

When it comes to the health of your used MP7 engine, there could be a group of issues contributing to its poor performance. In a worst case scenario, you could be faced with the only option being complete engine replacement. On the other hand, less severe issues may only require you to replace some parts or components. Of course, many engines can continue to run “OK” for a number of years, and these “tired” MP7’s are generally the best refresh candidates. In the end, cost, time, and availability will ultimately determine your decision, which is exactly why we spell out the pros and cons of buying a new Mack MP7 from the dealer below. Also make sure to take note that the Mack MP7’s horsepower rating may be a key factor in your decision.

Remanufacturing Process

A remanufactured MP7 long block from Big Bear Engine Company is a great replacement option for the customer who’s experienced a catastrophic internal engine failure. Coincidentally, a reman long block is an especially beneficial option if the customer still has functional, reusable external components, which can be swapped over from the old engine. Long blocks are a great alternative to buying new when you’re trying to reduce some of the costs associated with replacing an engine.

Our dedicated team of machinists and engine builders executes the full core tear down, cleaning, inspection, and machining of the engine before it leaves our facility. This ensures excellence with each engine we build.

We’ll also note that all of our remanufactured Mack MP7 long blocks are built with a combination of both reman and new parts. We do not recondition or refurbish old engine parts. Rather, we completely rebuild your old MP7 back to OEM specs.

Thorough Cleaning

Vigilant cleaning is essential during any remanufacturing process, and we begin by stripping the MP7, followed by putting the block, head, rods, crankshaft, and camshafts through a chemical jet wash or hot tank. This highly a thorough cleaning process ensures full adherence to Mack MP7 engine specs.


Before our quality control department inspects the finished product, the crankshaft is precision machined to the precise tolerances, polished, and then magnafluxed.

Cylinder Head

The cylinder head is resurfaced to assure a proper sealing surface with the block, as well as a finish that’s consistent with today's new gasket materials. Valve height is mic’d and each head is also vacuum tested to ensure correct valve seating.


Your MP7’s block is inspected for both cracks and imperfections using magnetic particle. The cylinders are then bored, honed, and inspected to precise tolerances. After that, we execute a process that’s geared toward eliminating the age-old culprit known as blow-by. This is achieved through torque plate honing, which eliminates the chances of cylinder distortion after the head is installed and torqued to the block.


The camshaft is inspected and precisely machined to provide the correct lift. Lobes are measured with a micrometer to make sure OEM tolerances are met.

Connecting Rods

In order to achieve an even distribution of stress across all the bearings, the connecting rods are comprehensively cleaned, machined to OEM specs, and then honed to the specified diameter for the original equipment. New bushings are fitted and machined in all bushed rods, and every connecting rod is also examined for bend and/or twist.

New Parts

All of our MP7 Mack long blocks receive a standard set of new parts such as pistons and rings, bearings, gaskets and seals, and liners. These new parts all but guarantee optimal performance and reliability for years to come. New parts are a combination of OEM and aftermarket, when available.

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Please fill out the form below with your information and request. A member of our staff will be with you shortly.

Remanufactured Engine Standards

We believe that to remanufacture is to make something as close to new as possible. This means that all wearable parts are automatically replaced. All MP7 core materials are then meticulously inspected and examined against original equipment specifications for the correct dimensional tolerances. Replacement parts are either new or re-qualified. If new, parts are made in the same production processes as original equipment. All testing is performed to manufacturer specifications and original production standards.

Mack MP7 Long Block Parts List:

MP7 Engine

  • Camshaft
  • Complete Loaded Cylinder Head
  • Liners
  • Intermediate Cover
  • Followers/Lifters
  • Block
  • New Upper and Lower Gasket Set
  • Pistons
  • Rings
  • Timed Front Gear Group
  • Crankshaft
  • Connecting Rods
  • **1 Year Warranty

*Note: We can provide a new oil pump, oil cooler, water pump, turbo, injectors, and fuel pump for an additional cost(s) with the long block, but these components will not come assembled to the engine.

**1-Year Warranty: First 6 Months Parts & Labor, Second 6 Months Parts Replacement Only. Ask your sales representative for a full copy of our remanufactured long block warranty.

MACK MP7 Specs

Engine Data

Type4-cycle, Direct Injection Diesel
ConfigurationInline-Six (I-6)
Bore4.84-inches (123 mm)
Stroke5.98-inches (152 mm)
Displacement11.0L (659 ci)
Compression Ratio16.0:1
Firing Order1-5-3-6-2-4
Torque Rise60-percent
Clutch Engagement1,121 lb-ft (1,647 n.m) at 800 rpm
Idle SpeedsLow: 600 rpm adjustable, high: 2,000 rpm
Engine Brake Retarding Power420 hp (372 kw) at 2,100 rpm
Dry Weight2,207 lbs (1,001 kg)

Give us a call today at 844-340-4114 for immediate sales and support for the Cummins 4BT, Cummins 6BT, 6CT, ISC, 855, QSB 4.5 L or CAT 3306. If you have any questions, check out our FAQ Page. We are always ready to help or just listen to your crazy off-roading adventures!

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