Home/Caterpillar C7 & C9 Parts/Caterpillar O-Ring, PAI 321287 (OEM 8L2777), Pack of 6
O-RING
Caterpillar · Models: 3100 / C7

Caterpillar O-Ring, PAI 321287 (OEM 8L2777), Pack of 6

Commercial diesel seal & o-ring. Match the listed part and engine identifiers before ordering.
2-Year WarrantyPAI Industries
$8.64
In stock — confirm dispatch timing 5 available
Fitment details

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PAI Part #321287
JAK'S Part #JAKS-321287
Catalog ref6L9795
Catalog ref8L2777
Catalog ref3066938
Catalog ref3947540
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Kit Membership

Used In These Kits

This part is included in 4 engine & overhaul kits — find yours below.

Complete The Rebuild

Suggested Additional Parts

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

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Caterpillar O-Ring, PAI 321287 (OEM 8L2777), Pack of 6
BrandPAI Industries
Part CategorySeals & O-Rings
Sub-TypeO-Ring
Engine MakeCaterpillar
Engine Model3100 · C7
ConditionNew
Stage / TierStandard

Pack of 6.

PAI 321287 is an o-ring. PAI lists Viton material. The listed durometer is 75. Listed cross section is 0.103 inch. Listed inside diameter is 0.424 inches. The manufacturer designates product-level OEM 8L2777.

Compatible Engines

PAI lists Caterpillar 3100 Series; Caterpillar C7 Engine. Match the complete required part number and listed application before ordering.

Manufacturer product cross-references
Caterpillar 6L9795
Caterpillar 8L2777
Cummins 3066938
Cummins 3947540
Cummins 3972753
Cummins 4062328
Mack 4333-355966R1
Navistar 355966
Navistar 355966R1
Caterpillar 5H6005
Mack 745-238328
Mack 745-242953

Compare the complete part number, material and required seal specification before ordering.

PAI Part #: 321287

OEM References:

  • CATERPILLAR 6L9795
  • CATERPILLAR 8L2777
  • CUMMINS 3066938
  • CUMMINS 3947540
  • CUMMINS 3972753
  • CUMMINS 4062328
  • MACK 4333-355966R1
  • NAVISTAR 355966
  • NAVISTAR 355966R1
  • CATERPILLAR 5H6005
  • MACK 745-238328
  • MACK 745-242953

Applications:

  • CATERPILLAR 3100 SERIES
  • CATERPILLAR C7 ENGINE

Warranty: 2.0 year(s)