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Caterpillar · Engine
9Y-2988
In stock · ships from Knoxville
This is a Caterpillar OEM engine breather assembly, also known as a valve cover breather or ventilation breather.
Confirm the part fits before you buy. Applications and interchange numbers are researched and audited per part.
Verified fitment for 4 applications
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All confirmed applications for this part number.
Caterpillar
Caterpillar
Confirmed for Caterpillar 3406A, 3406B, 3406C, and 3406E engines. Always verify engine serial number compatibility before purchase.
Part data verified against 5 catalog sources
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It mounts on the valve cover to vent excess crankcase pressure and prevent oil leaks and seal damage. A clogged or failed breather can cause internal pressure buildup, leading to oil consumption, gasket failures, and reduced engine performance. Replace it if you see excessive oil mist around the valve cover or if routine service intervals call for breather maintenance on your older CAT 3400 series diesel engine.
Part Number: 9Y-2988
BREATHER VENT / G11L1
Vendor: STOWERS MACHINERY
Dealer: Post Onsite
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