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Cummins 6CT8.3L Diesel Injection Pump Drive Gear, 3931378

Cummins 6CT8.3L Diesel Injection Pump Drive Gear, 3931378

SKU: K3931378
$18198
Out of Stock
Currently unavailable
Condition: New Aftermarket
Cross-References: 3931378, 3906968
The RF Engine Advantage
Family Operated Since 1975

Original Equipment Quality

Parts that meet or exceed OEM specifications. Guaranteed performance you can trust. Reliability built into every component.

100+ Years of Expertise

A century of collective diesel knowledge and 10+ acres of engines and engine parts, we are more than just an online reseller or call center. We know heavy-duty diesel.

Here for the Long Haul

Same location and same phone number for the last 50 years. Same commitment to getting you the right parts at the right price.

New, Reman, & Used

RF Engine offers an expansive offering of new aftermarket, remanufactured, and used engines and engine parts all under one roof.

Details

Case (Case IH) 7230 Tractor Thru JJA0064977 w/ 6CT8.3L engine
Case (Case IH) 1150E Crawler w/ 6C8.3 engine
Case (Case IH) 821B Wheel Loader Thru JEE0050600 w/ 6CT8.3L engine
Case (Case IH) 1150E Crawler w/ 6CT8.3L engine
Case (Case IH) 721B Wheel Loader Thru JEE0053199 w/ 6CT8.3L engine
Case (Case IH) 1155E Crawler w/ 6C8.3 engine
Case (Case IH) 7110 Tractor w/ 6CT8.3L engine
Case (Case IH) 1150E Crawler w/ 6C8.3 engine
Case (Case IH) 1155E Crawler w/ 6C8.3 engine
Case (Case IH) 9040B Excavator Thru DAC04#2000 w/ 6CT8.3L engine
Case (Case IH) 9310 Tractor Thru #JEE0036500 w/ 6CT8.3L engine
White 6175 Tractor w/ 6CT8.3L engine
Case (Case IH) 1155E Crawler w/ 6CT8.3L engine
Case (Case IH) 1660 Combine 1660 After JJC0038346 w/ 6CT8.3L engine
Case (Case IH) 9040 Excavator w/ 6CT8.3L engine
Case (Case IH) 7120 Tractor w/ 6CT8.3L engine
Case (Case IH) 7130 Tractor w/ 6CT8.3L engine
Case (Case IH) 2166 Combine Thru JJC0179999 w/ 6CT8.3L engine
Case (Case IH) 7220 Tractor Thru JJA0064977 w/ 6CT8.3L engine
Case (Case IH) 1666 Combine w/ 6CT8.3L engine
Case (Case IH) 7210 Tractor w/ 6CT8.3L engine
Case (Case IH) 9210 Tractor w/ 6CT8.3L engine
Case (Case IH) 7110 Tractor w/ 6CT8.3 engine
White 2500 Combine w/ 6CT8.3 engine
Case (Case IH) 1150E Crawler w/ 6CT8.3 engine
Allis Chalmers R52 Combine w/ 6CT8.3 engine
Case (Case IH) 9110 Tractor w/ 6CT8.3 engine
Case (Case IH) 9210 Tractor w/ 6CT8.3 engine
International TD-15E Crawler w/ 6CT8.3 engine
Allis Chalmers R42 Combine w/ 6CT8.3 engine
Case (Case IH) 7130 Tractor w/ 6CT8.3 engine
White 160 Tractor w/ 6CT8.3 engine
Case (Case IH) 721 Wheel Loader w/ 6CT8.3L engine
Case (Case IH) 721 Wheel Loader w/ 6CT8.3 engine
Case (Case IH) 821 Wheel Loader w/ 6CT8.3L engine
Case (Case IH) 7120 Tractor w/ 6CT8.3 engine
Case (Case IH) 1660 Combine w/ 6CT8.3 engine
White 6175 Tractor w/ 6CT8.3 engine
Case (Case IH) 1155E Crawler w/ 6CT8.3 engine
Case (Case IH) 1187C Feller Buncher w/ 6CT8.3 engine
Case (Case IH) 821 Wheel Loader w/ 6CT8.3 engine
Case (Case IH) 1550 Crawler w/ 6CT8.3 engine
White 170 Tractor w/ 6CT8.3 engine
Allis Chalmers R52 Combine w/ 6CT8.3L engine
Allis Chalmers R42 Combine w/ 6CT8.3L engine
OEM Part Number Cross Reference(s): 3906968, 3931378, 3935455, 3912614, J935455, J931378, J912614

Warranty Information

Overview

We stand behind every part we sell — new, rebuilt, or used. While RF Engine is not the manufacturer and cannot extend additional warranties, we do guarantee that each product will arrive as described, in usable condition, and free from material defects or misrepresentation.


Warranty Coverage

  • New Parts: Covered under the original manufacturer’s warranty. All terms and coverage are set by the manufacturer. Copies available upon request.
  • Rebuilt, Reconditioned, and Used Parts: Backed by an inspection-only warranty unless otherwise stated. As with new parts, RF Engine cannot provide further warranty coverage beyond the manufacturer’s terms.
  • No Additional Warranty: RF Engine does not offer any express or implied warranties. However, if an issue arises, we are here to assist and will support you through any applicable manufacturer claim process.

Our Guarantee

All parts are guaranteed to be in the condition stated at the time of sale and free from misrepresentation. If something isn’t right, we’ll work with you to resolve it — including returns, exchanges, or refunds when appropriate.

  • We sell parts — we don’t make them — but we stand behind what we sell.
  • Guaranteed to match the description or your money back.
  • Manufacturer’s warranty applies where available; we’ll help if you ever need it.

Used Parts — What to Expect

Used parts are cleaned, inspected, and guaranteed to be usable, but please note:

  • They often have signs of wear, surface rust, blemishes, or cosmetic imperfections.
  • They may include old gaskets or residue and likely require further cleaning or machining before installation.
  • They are not refurbished, remanufactured, or restored to like-new appearance.

We recommend careful inspection and strongly encourage installation by a qualified heavy-duty diesel mechanic.

  • Worn, not worn out — used parts may show signs of age but are fit for service.
  • All used parts are tested for usability, not appearance.

Questions?

If you have questions about a part’s condition, warranty, or how we handle returns and guarantees, feel free to contact us. We’re here to help.


Last Updated: June 22, 2025

All specifications and numbers are provided for reference only and should be independently verified before use. While we guarantee our parts match their descriptions and accept returns for any discrepancies, we cannot be held liable for installation costs, modifications, or consequential damages. Questions about compatibility? Contact our parts experts at 800-828-6943, sales@dieselcranks.com, or via live chat, Mon-Fri 8am-5pm EST.