Home/Caterpillar 3400 Series Parts/Caterpillar Buna N O-Ring, PAI 321253 (OEM 1S8947), Pack of 5
O-RING
Caterpillar · Models: 3400

Caterpillar Buna N O-Ring, PAI 321253 (OEM 1S8947), Pack of 5

Commercial diesel seal & o-ring. Match the listed part and engine identifiers before ordering.
2-Year WarrantyPAI Industries
$14.95
In stock — confirm dispatch timing 3 available
Fitment details

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PAI Part #321253
JAK'S Part #JAKS-321253
Catalog ref1S8947
Catalog ref5P3949
Catalog ref77-6629
Catalog ref776629
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Kit Membership

Used In These Kits

This part is included in 8 engine & overhaul kits — find yours below.

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Caterpillar Buna N O-Ring, PAI 321253 (OEM 1S8947), Pack of 5
BrandPAI Industries
Part CategorySeals & O-Rings
Sub-TypeO-Ring
Engine MakeCaterpillar
Engine Model3400
ConditionNew
Stage / TierStandard

Pack of 5.

PAI 321253 is a Buna N o-ring; PAI specifies a 0.676-inch inside diameter and 0.070-inch cross section. The manufacturer-designated reference is Caterpillar OEM 1S8947.

Compatible Engines

PAI lists Caterpillar 3400 Series applications. Match the original part number and listed application.

PAI lists these manufacturer references: Caterpillar 1S8947; Caterpillar 5P3949; Caterpillar 77-6629; Caterpillar 776629; Caterpillar 7X9277; Caterpillar 8T6447; Cummins 193734; Cummins 3330478; Detroit Diesel 4991539.

Compare the complete part number and required specification before ordering.

PAI Part #: 321253

OEM References:

  • CATERPILLAR 1S8947
  • CATERPILLAR 5P3949
  • CATERPILLAR 77-6629
  • CATERPILLAR 776629
  • CATERPILLAR 7X9277
  • CATERPILLAR 8T6447
  • CUMMINS 193734
  • CUMMINS 3330478
  • DETROIT DIESEL 4991539

Applications:

  • CATERPILLAR 3400 SERIES

Warranty: 2.0 year(s)