AMSOIL ASF-15 Oil Filter – Ford FL-1A Family (Legacy)
Free returns on all eligible orders
You have 30 days to request a return. All sale items are final sale.
AMSOIL ASF-15 Oil Filter – Ford FL-1A Family (Legacy)
The AMSOIL ASF-15 is a legacy, long-format spin-on oil filter designed for full-flow engine lubrication service. It removes abrasive contaminants from circulating oil while maintaining the flow needed to protect bearings, journals, and other internal engine components.
ASF-15 belongs to the widely used Ford FL-1A filter family. Legacy references identify a 3/4"-16 mounting thread, an approximate height of 5.16 inches, and an outside diameter of approximately 3.82 inches. It was followed by the AMSOIL SDF15 and later EAO15 filter designations.
Note: ASF-15 is a discontinued legacy AMSOIL part number. If you are sourcing a replacement for an engine returning to service, a fresh current-production equivalent (such as the WIX 51515 or Motorcraft FL-1A) is normally the safer choice — old-stock filters may have aged or hardened sealing gaskets regardless of physical appearance.
Key Features
- Full-flow spin-on engine oil filter
- Legacy AMSOIL Super Duty filter
- Long-format filter body for increased filtration capacity
- Thread size: 3/4"-16
- Approximate height: 5.16 in / 131 mm
- Approximate outside diameter: 3.82 in / 97 mm
- Commonly associated with the Ford FL-1A filter specification
- Designed for gasoline, diesel, and heavy-duty applications using the corresponding filter head
- Legacy AMSOIL part number: ASF-15
Engine Compatibility
The ASF-15 cross-references to the Ford FL-1A and WIX 51515 filter family. This filter specification is associated with a broad range of older Ford engines and related equipment, including:
- Ford 289 and 302 / 5.0L V8 engines
- Ford 351 / 5.8L V8 engines
- Ford 390, 427, 428, 429, and 460 V8 applications
- Chrysler, Mazda, Toyota Land Cruiser, and heavy-equipment applications
- Ford-based inboard and sterndrive marine engine installations
The current WIX 51515 equivalent uses a 3/4"-16 thread, measures approximately 5.20 inches high, and includes an 8–11 psi bypass valve and anti-drainback valve.
Fitment Notice
Confirm the number printed on the existing filter and verify the engine model, serial number, and filter-head configuration before ordering. Many filters use the same 3/4"-16 mounting thread — a filter that screws onto the engine may still have an incorrect gasket diameter, bypass-valve setting, anti-drainback arrangement, or body length. Marine engines may also have remote-filter adapters or restricted installation clearance. Because ASF-15 is a discontinued legacy number, confirm that any modern replacement matches the engine application rather than relying only on a cross-reference chart.
When to Replace
Replace the oil filter whenever the engine oil is changed or at the interval specified by the engine manufacturer. Earlier replacement may be appropriate following extended trolling or low-speed operation, heavy-load or high-temperature use, fuel, coolant, water or debris contamination, long periods of seasonal storage, internal engine repairs, or abnormal oil-pressure conditions. Do not install an old-stock filter if its gasket has hardened, its body is corroded or dented, or its storage history is unknown.
Installation Notes
Remove the existing filter and confirm its sealing gasket has not remained on the filter head. Clean the mounting surface and compare the new filter’s thread, gasket, and overall dimensions with the removed filter. Lightly coat the new gasket with clean engine oil and install by hand to the manufacturer’s tightening specification — do not overtighten. After installation: refill with the specified oil, start the engine and confirm normal oil pressure, inspect for leakage, shut down and allow oil to settle, then recheck and correct the oil level.
Cross-Reference & Superseded Part Numbers
- AMSOIL ASF15 / ASF-15 (legacy)
- AMSOIL SDF15 (successor)
- AMSOIL EAO15 (current)
- Motorcraft FL-1A
- WIX 51515
- NAPA Gold 1515
- Baldwin B2
- Donaldson P550008
- Fleetguard LF3313
- FRAM PH8A
- Purolator L30001
- Ford CM-6731-FL1A
Cross-reference numbers are comparison aids only. Confirm the original application and internal filter specifications before substituting brands.
Parts Desk Insights
ASF-15 is an older AMSOIL number for the familiar Ford FL-1A-size filter. The main concern with old stock is not simply whether it fits — the age and condition of the sealing gasket also matters. For an engine returning to service, a fresh current-production equivalent such as the WIX 51515 or Motorcraft FL-1A is normally the safer choice. If you specifically need the AMSOIL product line, the current designation is EAO15.
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.