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Cummins 4B 3.9L, 6B 5.9L, 4B 4.5L Inframe Engine Rebuild Kit, New (IF4089185RGT)

โ€“ Replace Part Number: IF4089185RGT
โ€“ Fit for: Cummins 4B 3.9L, 6B 5.9L, 4B 4.5L engines
โ€“ Built to OEM specs for a proper fit
โ€“ Send us an inquiry for price

Engine Serial Number (ESN) โ€” Have your engine serial number? Enter it here. We can use it to help review whether this part matches your engine.
SKU: P0263859
30-Day Money Back

Hassle-free 30-day return policy for a risk-free shopping experience.

3 Months Warranty

Enjoy 3-month warranty, ensuring long-lasting reliability and peace of mind.

2-7 Days Fast Delivery

Receive your order within 2 to 7 days, ensuring fast and reliable delivery.

24/7 Service

Round-the-clock support to assist you whenever you need it.

  • 30-Day Money Back
  • 2-7 Days Fast Delivery
  • 6 Months Warranty
  • 24/7 Service

Product Details

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?ย 

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 sellย Rebuild Kits with new parts, zero core charges, and a 6-month warranty.ย On top of only offering premium quality parts, we also make sure youย save up to 50% off OEM prices.ย So, when it comes to your rebuild, what’s left to want?ย 

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

  • Kick your old engine to the curbwith a rebuild that willย restore your engine to great working condition and extend the life of it. It is sound investment that will pay off for years to come.ย 
  • Give your engine a backbone withย rod and main bearings constructed with a Tri-Metal material. These are made to last!
  • Go the extra mile, or a million extra miles withย Piston Pins that are hardened and tempered for improved strength and wear resistance that you can count on.ย 
  • Don’t overpay! Quality willย meet or exceed the OE’s at a much lower price.ย Don’t settle forย ridiculous OE pricesย when you canย save some hard earned cash.ย 
  • Adding to the savings,ย all new parts are included and there is no core charge.ย You can’t beat that!ย 
  • Also, fitment and functionalityย will not be a problem becauseย strict OE specificationsย are met giving you theย best of both.
  • Trust the expertsย with a Rebuild Kit manufactured and assembled in anย ISO 9001:2008 certified facility. Simply put, it’sย quality and consistencyย you can trust.ย 
  • You’llย rest peacefullyย knowing the pistons included areย CNC turned to precise tolerancesย making your life easier. To top it off, they are built withย long lasting strength and durabilityย forย ultimate performance.ย 
  • Additionally,ย computer controlled piston machiningย is used toย maintain proper clearances,ย giving youย peace of mind when out on the road.
  • Keep oil where it needs to be withย Oil Control Rings designed with precise tangential tensionย for maximum oil control. Your engine will beย properly lubricated and ready to goย when you need it. Adding onto that, the sealing products included areย proudly USA madeย and are composed ofย 100% Asbestos-Free Material!
  • Let’s seal the deal. The gaskets included are used with proper materials forย maximum sealing performance,ย keeping your fluids whereย they need to be.ย It simply doesn’t get better than that!

Kit Contents

  • (6) Connecting Rod Bearings
  • (1) Main Bearing
  • (6) Connecting Rod Bearings
  • (1) Flange Gasket
  • (1) Oil Pan Gasket
  • (6) .50mm Piston Kits
    • (12) Piston Pin Retainers
    • (6) Piston Pins
    • (6) .50mm ISB Engine Pistons
    • (6) Piston Ring Sets
      • (6) Top Piston Rings
      • (6) .50 Second Piston Rings
      • (6) Oil Rings
  • (1) Upper Gasket Set
    • (1) Rocker Cover Housing Gasket
    • (4) Lock Plates
    • (1) Oil Drain Gasket
    • (2) O-Ring Seals
    • (1) Turbo Hose O-Ring Seal
    • (1) O-Ring Seal
    • (1) Rocker Cover Gasket
    • (1) Seal
    • (6) O-Ring Seals
    • (6) Exhaust Manifold Gaskets
    • (3) Sealing Washers
    • (21) Seaing Washers
    • (1) Exhaust Rcn Valve
    • (4) Connection Gaskets
    • (1) Rectangular Seal
    • (1) Turbocharger O-Ring Seal
    • (10) Sealing Washers
    • (4) Sealing Washers
    • (2) O-Ring Seals
    • (4) Sealing Washers
    • (1) Intake Manifold Gasket
    • (1) Thermostat Seal
    • (1) Copper Gasket
    • (1) Accessory Drive Cover Gasket
    • (1) O-Ring Seal
    • (1) O-Ring Seal
    • (2) O-Ring Seals
    • (6) O-Ring Seals
    • (1) Cylinder Head Gasket
    • (1) O-Ring Seal
    • (1) O-Ring Seal
    • (6) Mid Range XPI Injector Seals
    • (6) O-Ring Seals
    • (1) Turbocharger Gasket

Warranty

6-month warranty.

What Rebuild Kit and Gasket Set Includes

Qty Component Part Number
6 Connecting Rod Bearings 4893693
1 Main Bearing 3802070, 3800290, 861260, 4955853
6 Connecting Rod Bearings 3969562, CUM3901170, 3939859, 3901230, 3901170
1 Flange Gasket 3949562
1 Oil Pan Gasket 3959797, 3955106, 4337596
6 .50mm Piston Kits 4089185
12 Piston Pin Retainers 3920691, CUM3901706, 3901706, 3284366
6 Piston Pins 3934047, 3919053, CUM3934047
6 .50mm ISB Engine Pistons 3949843
6 Piston Ring Sets 4089181, 3957244, 3949579
6 Top Piston Rings 3957244
6 .50 Second Piston Rings 3943545
6 Oil Rings 3933585
1 Upper Gasket Set 4089263OS
1 Rocker Cover Housing Gasket 3963379, 3955109
4 Lock Plates 4933628, 3990120, 3937704
1 Oil Drain Gasket 4931365, 3949499, 5264568
2 O-Ring Seals 3928624
1 Turbo Hose O-Ring Seal 3922794, 3883963
1 O-Ring Seal 3678603
1 Rocker Cover Gasket 3954324
1 Seal 3906698, CUM3906698
6 O-Ring Seals 3087740
6 Exhaust Manifold Gaskets 5266422, 5447591, 3955339
3 Sealing Washers 3963988, 3937155, 3935172
21 Seaing Washers 3963983, 3935171, 3918191, 3903037, 3283280
1 Exhaust Rcn Valve 3949417
4 Connection Gaskets 3949910
1 Rectangular Seal 3949916
1 Turbocharger O-Ring Seal 3066211
10 Sealing Washers 4934278, 3963989, 3947872
4 Sealing Washers 4934279, 3963992, 3957769
2 O-Ring Seals 3958414
4 Sealing Washers 3963981, 3935168
1 Intake Manifold Gasket 3947530
1 Thermostat Seal 3954829
1 Copper Gasket 3920773, 3900216
1 Accessory Drive Cover Gasket 3955457
1 O-Ring Seal 4010519, 3330202
1 O-Ring Seal 3883284, CUM3883284
2 O-Ring Seals 3957131
6 O-Ring Seals 4890926
1 Cylinder Head Gasket 3966342
1 O-Ring Seal 3966343
1 O-Ring Seal 3973512, 3990084, 145533
6 Mid Range XPI Injector Seals 3937142
6 O-Ring Seals 4062328, 3972753, 3947540
1 Turbocharger Gasket 3949530
Brand4BTdiesel
Compatible BrandFor CUMMINS
Compatible Engine BrandFor CUMMINS
ConditionNew

Shipping Spec

Weight16.329 kg
Dimensions110.5 × 33.0 × 34.3 cm

โ€“ Replace Part Number: IF4089185RGT
โ€“ Fit for: Cummins 4B 3.9L, 6B 5.9L, 4B 4.5L engines
โ€“ Built to OEM specs for a proper fit
โ€“ Send us an inquiry for price

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Warranty

For new Cummins parts, we provide 90-day warranty. Quality is our commitment. 4BTDiesel ensures your peace of mind! For complete warranty details, please view our Warranty Policy.

Shipping

We ship worldwide and offer full expedited delivery to ensure your construction machinery back in action, fast. Check out our Shipping Policyย for more details.

Easy Return

We prioritize your satisfaction. If your order doesn't meet your expectations within 90 days, you may be eligible for a refund. See our Easy Return Policy for details.