Featured Product

  • Long Block Assembly
  • Part #: RP1336
  • For 8.3L Cummins 6 cylinder engines with single thermostat.

Customizable Long Blocks for 3.9, 5.9 & 8.3 Liter Engines

Reliance Power Parts is pleased to announce new long blocks for the Cummins 3.9, 5.9 and 8.3 liter engines. These long blocks are 100% new and are sold outright - no core needed. The B and C series engines are used in many different applications ranging from light trucks to a wide variety of agricultural, industrial, and marine applications.

Reliance long blocks are currently available in the 2 valves per cylinder head version, with individual valve covers for each cylinder (late models utilize 4 valves per cylinder and a single valve cover.)

Each of these long blocks is completely new and built from the bare block up using Reliance parts to create a long block specific to your customer’s application. Reliance long block assemblies will give you access to both high-quality parts and our extensive knowledge. All specifications and tolerances are checked and verified throughout the build process. With a quick turnaround time, these engines will spend less time out of commission and more time working - right where they need to be! Warranty coverage is 1 year or 2,000 hours / 50,000 miles, whichever comes first, from date of invoice on the long block only. Labor is not included.

We are also offering a do-it-yourself long block kit. These kits include all the new parts and components needed to assemble a complete long block. Now you have the option of building the long block yourself or receiving one already assembled.

When you demand flexibility and convenience, ordering a long block from Reliance guarantees you will receive all new components without the hassle of a core return.