What You're Getting
This is a panel/round engine air filter built for Peterbilt and Kenworth trucks running the common Class 8 air intake housing - think 379, 389, 567, T680, W900 territory depending on year and engine option. It's a straightforward drop-in filter, not some universal-fit foam cone deal.
P637453 is the primary filter number, P621725 shows up as a companion or safety filter depending on how the housing's configured on your truck. Some setups run just the one, some run both stacked - that's why we list both, so check what you're pulling out before you order.
Why These Numbers Cross
Fleetguard AF25557, Baldwin PA4857, Luber-finer LAF6725A, and Torque Parts TR513-EF all cross to this filter because they're built to the same media specs, seal diameter, and pleat count for this housing - not because everybody copied off Peterbilt's homework. Filter manufacturers make these to fit the housing dimensions, and several brands land on the same spec sheet.
Where guys get burned is assuming any 'round air filter that looks about right' will seal up. Seal diameter and overall height matter here - a filter that's a half inch short won't seat right in the housing lip and you'll get dirt bypass, which is worse than running a dirty filter. Pull your old filter and check the number stamped on the end cap or the housing tag before ordering.
If your old part doesn't show a number anymore, give us the VIN - Peterbilt and Kenworth build sheets tell us exactly which housing and filter combo left the factory.
Ordering From PartStop
We're in Tacoma and keep this filter in stock for same-day pickup or will size it up over the counter if you bring in the old one. Ship nationwide too if you're not local - most orders go out same day.
Comes with our standard 6+ month warranty. If it doesn't seat right or seal up in your housing, call us before you toss the packaging - we'll sort it out.
P637453 Cross-Reference & Interchange Numbers
These manufacturer and aftermarket numbers commonly cross-reference to P637453. Use them to identify the part — then confirm the exact fit by VIN or the number stamped on your old unit before you order. An interchange is a starting point, not a fitment guarantee.
| Brand / Line | Cross-Reference Numbers |
|---|---|
| Luber-finer | LAF6725A |
| Torque Parts | TR513-EF |
| Fleetguard | AF25557 |
| Baldwin | PA4857 |
Frequently asked questions
Does P637453 fit my Kenworth W900?
Depends on the intake housing your truck's running - not every W900 year and engine combo uses this filter. Give us the VIN or pull the number off your old filter's end cap and we'll confirm before you order.
Is this the same as the Fleetguard AF25557?
They cross-reference to the same fit and seal spec, yes. Not the identical part off the same assembly line, but built to fit the same housing. Confirm against your old filter's number if you're not sure which one your truck actually needs.
Do I need both P637453 and P621725, or just one?
Some Peterbilt/Kenworth housings run a single filter, others stack a primary and a safety filter. Pop the housing open and see what's actually in there now - that tells you if you need one or both.
Not sure it fits? We check before you pay.
Run your VIN and we’ll match parts to your exact truck, or call the counter — a person who knows trucks verifies fitment by OEM number before the order ships. No wrong-box returns.
More cross-reference guides
Need the part, not just the reading?
Every part below is a Premium Quality aftermarket Direct Replacement with published OEM cross-reference numbers, a 6+ month warranty and same-business-day shipping from Tacoma, WA. Not sure it fits? Run your VIN — or call and a person who knows trucks will verify fitment before you pay.