Cummins 4B 3.9L, 6B 5.9L, 4B 4.5L Inframe Engine Rebuild Kit, New (IF4089420)

Think you know the truth about Aftermarket Rebuild Kits? We’d bet you’d be surprised.
It’s no secret, rebuilding your rig is one of the most labor (and wallet) intensive repairs out there. Sure, you want your engine to last another million miles but you also want the best price; so what should you choose- OEM or Aftermarket? 

When it comes to engine parts, the aftermarket often gets a bad rep. The idea that aftermarket retailers sell cheap parts with zero warranty, delivered in a beat-up box written in another language couldn’t be further from the truth. 4BTdiesel is here to set the record straight; we only sell Rebuild Kits with new parts, zero core charges, and a 6-month warranty. On top of only offering premium quality parts, we also make sure you save up to 50% off OEM prices. So, when it comes to your rebuild, what’s left to want? 

Need a little extra proof? Let’s talk Rebuild Kits.

• Kick your old engine to the curbwith a rebuild that will restore your engine to great working condition and extend the life of it. You can’t beat that!
• Give your engine a backbone with rod and main bearings constructed with a Tri-Metal material. There’s no doubt it will be running until the cows come home. 
• Go the extra mile, or a million extra miles with Piston Pins that are hardened and tempered for improved strength and wear resistance. The sheer power of these bad boys will keep you on the road and not on the side of it. 
• Don’t pay more when you can pay less! Quality will meet or exceed the OE’s at a much lower price. Don’t settle for ridiculous OE prices when you can save your hard earned cash.
• Adding to the savings, all new parts are included and there is no core charge. Plus, to save time kits components are packed in subassemblies by function, making installation easy. 
• Also, fitment and functionality will not be a problem because strict OE specifications are met giving you the best of both.
• Trust the experts with a Rebuild Kit manufactured and assembled in an ISO 9001:2008 certified facility. Simply put, it’s quality and consistency you can rely on.
• You’ll sleep soundly knowing the pistons included are CNC turned to precise tolerances making your life easier. To top it off, they are built with long lasting strength and durability for ultimate performance. 
• Additionally, computer controlled piston machining is used to maintain proper clearances, giving you peace of mind when out on the road.
• Keep oil where it needs to be with Oil Control Rings designed with precise tangential tension for maximum oil control. Your engine will be properly lubricated and ready to go when you need it. Adding onto that, the sealing products included are proudly USA made and are composed of 100% Asbestos-Free Material!
• Let’s seal the deal. The gaskets included are used with proper materials for maximum sealing performance, keeping your fluids where they need to be. You won’t be that guy with the puddle under his rig!

Kit Contents

• (1) Oil Pan Gasket
• (1) Lower Thrust Bearing
• (1) Main Bearing
• (1) Gasket
• (6) Connecting Rod Bearings
• (6) .50mm Piston Kits
• (12) Piston Pin Retainers
• (6) Piston Pins
• (6) .50mm ISB Engine Pistons
• (6) .50mm Piston Ring Sets
• (6) Top Piston Rings
• (6) .050 Second Piston Rings
• (6) Oil Rings
• (6) Connecting Rod Bearings
• (1) Upper Engine Gasket Set
• (1) 1.25mm Cylinder Head Gasket
• (6) O-Ring Seals
• (1) Thermostat O-Ring Seal
• (12) O-Ring Seals
• (1) O-Ring Seal
• (2) Sealing Washers
• (2) O-Ring Seals
• (1) Turbo Oil Drain Gasket
• (2) O-Ring Seals
• (1) Filler Cap Gasket
• (6) Sealing Washers
• (1) Cylinder Head Gasket
• (1) Turbo O-Ring Seal
• (1) Rocker Lever Housing Gasket
• (1) Valve Cover Gasket
• (6) Noise Isolators
• (6) Exhaust Manifold Gaskets
• (1) Turbocharger Gasket
• (1) Turbocharger Gasket
• (6) Plain Copper Washers

Warranty

6-month warranty.

What Rebuild Kit and Gasket Set Includes