Home/Caterpillar 3400 Series Parts/321278 Caterpillar 3406E / C15 / C16 O-Ring
O-RING
Caterpillar · Models: 3406E / C15 / C16 / C18 / 3400

321278 Caterpillar 3406E / C15 / C16 O-Ring

Commercial diesel seal & o-ring. Match the listed part and engine identifiers before ordering.
2-Year WarrantyPAI Industries
$22.20
In stock — ships same day 10 available
Help us verify fitment

Provide every identifier you have. A specialist will use these details to confirm the application before fulfillment.

Secure Checkout Review Return Policy Warranty Details Ask About Same-Day Shipping
PAI Part #321278
JAK'S Part #JAKS-321278
Cross Ref109-0077
Cross Ref1090077
Cross Ref4F7387
Not sure it's the right fit? Call a specialist
(720) 445-6249
Talk to a tech or text a photo of your part tag — we'll confirm fitment before you buy
Kit Membership

Used In These Kits

This part is included in 16 engine & overhaul kits — find yours below.

Complete The Rebuild

Suggested Additional Parts

Commonly sold with this product. These parts are sold separately.

  1. Cat / Caterpillar WATER CONNECTOR GASKET (Pack of 5)
    331372Cat / Caterpillar WATER CONNECTOR GASKET (Pack of 5) In stock
    $57.75View ›
  2. Caterpillar 3406E / C15 / C16 O-Ring
    321294Caterpillar 3406E / C15 / C16 O-Ring In stock
    $47.40View ›
  3. Cat / Caterpillar THERMOSTAT
    381851Cat / Caterpillar THERMOSTAT In stock
    $32.65View ›
  4. Caterpillar 3406E / C15 / C16 Nut
    340061Caterpillar 3406E / C15 / C16 Nut In stock
    $9.12View ›
  5. Cummins N14 ENGINES C-BRAKE GASKET (Pack of 3)
    131428Cummins N14 ENGINES C-BRAKE GASKET (Pack of 3) In stock
    $26.22View ›
321278 Caterpillar 3406E / C15 / C16 O-Ring
BrandPAI Industries
Part CategorySeals & O-Rings
Sub-TypeO-Ring
Engine MakeCaterpillar
Engine Model3406E · C15 · C16 · C18 · 3400
ConditionNew
Stage / TierStandard