What You're Actually Buying
This is the outlet (downstream) NOx sensor, 12V, 4-pin connector, mounted after the SCR catalyst on Freightliner and Western Star trucks running the DD13 or DD15. It's reading the tailpipe-side NOx level to confirm the SCR is converting NOx like it should — that's different from the inlet sensor which reads before the cat.
Position matters here. Inlet and outlet sensors on these engines are not interchangeable with each other even though they can look similar from across the shop, so don't grab whichever one's closer to the bench.
Surest way to know you've got the right one: pull the old sensor and check the number stamped on it against A0101532328 or the cross numbers in our table. If your old part doesn't match anything on that list, stop and call us before you install it.
How These Cross Numbers Line Up
A0101532328 has run through a few Daimler part number revisions over the years — RA0101532328 and EA0101532328 show up as reman or updated versions of the same sensor. Bosch built these for Daimler, which is why 5WK97339A shows up as the Bosch-side number for the same physical part.
On the aftermarket side, Delphi and NTK/CTP style numbers like 285-1009, 285-1012, and 650621 cross to this same sensor, along with 3FL002 and 4707302 depending on who repackaged it. The 4-pin connector and wiring harness routing are what actually need to match — a sensor with the right electrical output but wrong connector shape isn't going in without cutting harness.
A0091530728 is close in number but is a different application — worth double-checking against your VIN before you order, since a one-digit-off part number on these Daimler castings can mean a completely different mounting thread or connector count.
Ordering From PartStop
We're in Tacoma and keep this one in stock for same-day pickup if you're local — walk in with the old sensor or just read us the number off it and we'll match it up at the counter.
Ship nationwide if you're not near us, usually next-day if you order before early afternoon. We've sent these to independent shops and fleets from California to Ohio.
Comes with our standard 6+ month warranty. If it doesn't read right after install, bring it back — but confirm the VIN and old part number before ordering so we're not doing that dance in the first place.
A0101532328 Cross-Reference & Interchange Numbers
These manufacturer and aftermarket numbers commonly cross-reference to A0101532328. 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 |
|---|---|
| OE/Cross-Ref | 5WK97339A, A0091530728, EA0101532328, RA0101532328, 285-1009, 650621 |
| Cross-Reference | 285-1012, 3FL002, 4707302, 577.46801 |
Frequently asked questions
Does A0101532328 fit my Freightliner Cascadia with a DD15?
Likely yes if it's the outlet NOx sensor position, but confirm against your VIN or the number stamped on the sensor you're pulling. DD15 aftertreatment setups changed some over model years, so don't assume off the engine family alone.
Is this the same as the Bosch 5WK97339A?
Same physical sensor, different label — Bosch built it for Daimler under that number. Functionally it's the same part, but still check your old sensor's number to be sure you're not dealing with an inlet-position sensor that looks similar.
How do I know if I need the inlet or outlet sensor?
Outlet sensor sits downstream of the SCR catalyst, closer to the tailpipe side of the aftertreatment box. If you're not sure which one failed, pull the fault code — it'll usually specify NOx sensor bank 1 or 2, inlet or outlet.
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.