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The 'LS' line of engines from GM has been hugely popular since they were first unveiled, taking over for the famous small block line of engines. The Gen III and Gen IV versions of the LS engines were offered in many pick up, van, SUV and car applications and ranged from 4.8L to 7.0L sizes. The later model versions of this engine feature Active Fuel Management (AFM) to increase fuel economy and decrease emissions.

Reliable Engines Direct remanufactured GM 5.3 and 6.0 L GM LS engines for sale are built to meet or exceed OEM standards and our backed by our standard 3 year, unlimited mileage nationwide warranty (private use applications). For total peace of mind you can also upgrade to our 'No Fault' Warranty Supplement, call for details. All R.E.D. remanufactured engines incorporate the latest updates to correct original design flaws

Reliable Engines Direct remanufactured 5.3 and 6.0 L GM LS engines are completely remanufactured including machining the block, crank, connecting rods and cylinder heads, and assembled with new or remanufactured parts. Rebuilt GM 5.3L and 6.0L LS engines will only correct the issue with the "core" engine used as raw material, but will typically not include any other machining or remanufacturing on the rest of the engine or have any updates performed. Used engines incorporate no updates and are extremely susceptible to failure due to mileage already being on the engine with questionable maintenance records. Used and rebuilt 5.3L and 6.0L LS engines are inferior, do not correct any of the original equipment design flaws and typically have very limited or pro-rated warranties. When shopping be sure to ask if you're getting a used, rebuilt 5.3L and 6.0L LS engine or a 100% remanufactured engine.



Cracked cylinder heads (coolant leaks)

  • R.E.D. pressure tests the cylinder heads twice to ensure there are no cracks in the cylinder head. Cylinder heads are first pressure tested individually and then once more when assembled on the engine. Some competitors only pressure test the cylinder heads before assembly which can not show cracks which are only visible when the heads are torqued to the cylinder block.

Leaking timing cover and/or oil pan

  • R.E.D. includes the timing cover and oil pan installed on this 2004 Ford F150 5.4 Triton engine. Timing covers are checked and machined for straightness to ensure a good seal. All engines are simulation tested and black light checked for leaks during testing.

Lifter noise (Gen IV)

  • R.E.D. only uses the most recent design of the Active Fuel Management (AFM) lifters for the best oil flow to reduce lifter noise on startup

Premature bearing failure or engine knocking

  • Blocks and cranks are completely remanufactured to exact tolerances utilizing CNC machining equipment

  • Crankshafts are micro-polished to extend bearing life. Unlike some competitors, the tape used for micro-polishing cranks at R.E.D. is only used once and in only one direction. Reusing tape back and forth can cause fine metal particles to become impregnated in the journal and cause premature failure.

  • R.E.D. 5.4L long blocks include the oil pan and pickup tube installed to avoid contamination issues. Some competitors offer the engine without the pickup tube installed which risks it being exposed to dirt/debris that will plug the pickup screen.

Low oil pressure

  • R.E.D. designed cam bearings provide tighter oil tolerances than OE cam bearings. These are not an "off-the-shelf" part number for any bearing manufacturer and were created in collaboration with one of the high quality bearing vendors R.E.D. works with.

  • A brand new oil pump is used for the most reliable pressure and flow (some competitors rebuild or reuse old oil pumps)

Oil consumption problems

  • R.E.D. installs an oil pressure relief valve baffle (OE part # 12639759) on all 2007 and later applications that did not have this included from the OE. This relief valve baffle redirects oil back to the oil pan.

  • Compression height on the pistons is reduced to maintain factory compression ratio specifications

  • Both the block and cylinder heads are precision machined to be exact specifications


  • Graphite coated hypereutectic pistons resist scuffing and damage to heat much better than factory aluminum pistons

  • Moly piston rings and steel compression rings reduce friction and cylinder wall wear to extend the life of the 2004 Ford F150 5.4 Triton engine

  • Fel-Pro® rear main seals protect against heat and leaks

  • Connecting rods are honed (both the little and big ends) to ensure uniformity, and bent rods are scrapped (some competitors will bend rods back into place)

  • Chrome plated valve stems resist scuffing and heat for greater durability

  • Soda blasting aluminum components provides a visually 'like new' raw material without the risk of contaminating the 5.4 liter Ford crate engine (some competitors blast with other abrasive materials which can become stuck in the 2004 Ford F150 5.4 Triton engine and cause the new engine to fail)

  • Every engine is 100% simulation tested very thoroughly by skilled technicians. Engines are checked for good compression, oil pressure, and black light checked for any leaks before packaging

  • Engines are provided with a written warranty which clearly outlines coverages. Unlike some competitors, Reliable Engines Direct warranties are not 'pro-rated' which decrease your coverage over time

  • Engines are shipped in plastic totes with simple core return instructions provided to make returning cores extremely simple

  • Excellent product support technicians aren't just order takers, they are knowledgeable customer service experts

  • You're buying your remanufactured Triton 5.4L direct from the manufacturer so you know you aren't dealing with a middle man for increased costs and headaches for warranty, core returns and technical assistance

Contact us today for a quote or if you have any questions

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