Cummins - Seal - 3909356
Free returns on all eligible orders
You have 30 days to request a return. All sale items are final sale.
The Cummins 3909356 Seal is an OEM replacement sealing component used on Cummins engine assemblies where this exact part number is specified. It is designed to help prevent leakage at its assigned sealing location and should be replaced whenever the related component is removed or the original seal shows wear, hardening, cracking, or seepage.
Key Features
- Genuine Cummins replacement seal
- Used where 3909356 is listed in the Cummins parts breakdown
- Helps prevent fluid or pressure leakage at the serviced component
- Recommended during engine service, repair, or rebuild work
- Correct replacement when the original seal number matches 3909356
Engine Compatibility
Fits Cummins applications that specifically call for seal 3909356. Confirm fitment by engine serial number, component assembly, and diagram location before ordering.
Serial Number Fitment Notice
Cummins seals can vary by diameter, profile, material, and installation location. Always verify by engine serial number and the original parts diagram before installation.
When This Part Needs Replacement
Replace this seal if it is leaking, brittle, flattened, cracked, swollen, cut, or disturbed during component removal. Reusing an old seal can lead to repeat seepage after reassembly.
Installation Notes
Clean the sealing bore, shaft, groove, or mating surface before installation. Avoid nicking or twisting the seal, and install it squarely according to the Cummins service procedure.
Alternate/Superseded Part Numbers
- 3909356
Parts Desk Insight
For seals, the exact part number matters more than appearance. A similar-looking seal may have the wrong profile or material for the Cummins assembly.
Shipping: Ships same or next day for fast Canada wide shipping. ⚓
Shipping information
In-stock and OEM parts: ship same or next business day.
Locally warehoused items: ship within 3–4 business days.
Special-order items: timeline confirmed after order.
Returns & warranty
Returns & Satisfaction Guarantee
We stand firmly behind the quality of every product we sell. Your confidence matters to us — and we back it with a straightforward 30-Day Satisfaction Guarantee.
If you are not fully satisfied, you may request a return within 30 days of delivery. All returns must receive pre-approval prior to being sent back. Unauthorized returns will not be accepted.
To qualify for a return:
Item must be in new, unused condition
Product must be in its original packaging
All parts, components, hardware, manuals, and accessories must be included
Packaging must be undamaged and suitable for resale
Important:
Electronics are strictly inspected. No returns on open-box electronics. Exceptions may apply only with prior written approval. Any electronic unit that has been installed, powered, activated, or altered may not be eligible for return.
We are serious about product integrity — and equally serious about taking care of our customers. If there is ever a product issue, contact us immediately so we can make it right.
For return authorization, please contact our support team before shipping anything back.