Piston ring set illustration – not the actual part
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Piston ring set illustration – not the actual partDiesel Parts Direct logo

Aftermarket parts may appear slightly different, including the packaging.

Cummins4BT / 6BTPiston Ring Sets

DS-4089974 Piston Ring Set For Cummins Diesel Engines

(.050 Oversize) 4B3.9 / 6B5.9 / ISB

OEM #: 4089974SKU: DS4089974
$46.55

Taxes and Shipping are calculated at checkout

Special Order Item - not eligible for return

This is a Piston Ring Set (.050 Oversize) for the following engine models:

  • 4B3.9
  • 6B5.9
  • ISB
  • ISD
  • ISF
  • ISG
  • QSB
SKU DS4089974
OEM Number 4089974
Part Type Piston Ring Sets
OEM Brand CUMMINS

Aftermarket warranty

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  • Orders are processed the same or next business day
  • Expedited shipping options available at Checkout
  • If same-day shipping is critical, please call to confirm availability

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Call any of our friendly Parts Dept. Specialists with your engine serial number, and we can quickly verify whether this part is the correct part for your engine — no guesswork.

Phone: 888.687.0539

Don't know how to find your engine serial number? Go to our Engine Help Center for assistance.