Home/Caterpillar 3400 Series Parts/Caterpillar Buna N O-Ring, PAI 321216 (OEM 5K5959), Pack of 6
O-RING
Caterpillar · Models: 3400

Caterpillar Buna N O-Ring, PAI 321216 (OEM 5K5959), Pack of 6

Commercial diesel seal & o-ring. Match the listed part and engine identifiers before ordering.
2-Year WarrantyPAI Industries
$17.94$19.74 Save $1.80
In stock — confirm dispatch timing 6 available
Fitment details

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PAI Part #321216
JAK'S Part #JAKS-321216
Catalog ref078-1986
Catalog ref0781986
Catalog ref2U0902
Catalog ref5E2393
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Kit Membership

Used In These Kits

This part is included in 6 engine & overhaul kits — find yours below.

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Caterpillar Buna N O-Ring, PAI 321216 (OEM 5K5959), Pack of 6
BrandPAI Industries
Part CategorySeals & O-Rings
Sub-TypeO-Ring
Engine MakeCaterpillar
Engine Model3400
ConditionNew
Stage / TierStandard

PAI 321216 is a buna n o-ring for Caterpillar applications. PAI specifies Buna N construction. The manufacturer designates product-level OEM 5K5959. PAI cross-references Caterpillar 5K5959. PAI lists these application categories: Caterpillar 3400 Series. Confirm the complete required part number before ordering.

Pack of 6.

Manufacturer product cross-references
Caterpillar 078-1986
Caterpillar 0781986
Caterpillar 2U0902
Caterpillar 5E2393
Caterpillar 781986
Caterpillar 8T7177
Cummins 145608
Cummins 3028291

PAI Part #: 321216

OEM References:

  • CATERPILLAR 078-1986
  • CATERPILLAR 0781986
  • CATERPILLAR 2U0902
  • CATERPILLAR 5E2393
  • CATERPILLAR 5K5959
  • CATERPILLAR 781986
  • CATERPILLAR 8T7177
  • CUMMINS 145608
  • CUMMINS 3028291

Applications:

  • CATERPILLAR 3400 SERIES

Warranty: 2.0 year(s)