What This Sensor Does And Where It Lives
This is a NOx sensor, plain and simple - it sits either pre or post SCR (you've usually got two on these trucks) and tells the ECM how much NOx is coming out versus how much is left after the doser and cat do their job. When it goes bad or drifts out of range you get derates, DEF system codes, and sometimes a truck that just won't make power.
It's built for Detroit Diesel engines in Freightliner and Mercedes-Benz (MB) applications - think Cascadia and similar platforms running DD engines. The 5WK9 7340A stamp you see is the Continental/supplier casting number, which is common - Detroit doesn't build these sensors in-house, they buy them from the same handful of suppliers everyone else does.
Two sensors, two locations, and they're not always interchangeable position-to-position depending on year and harness routing. That's why the part number off your old sensor matters more than just knowing it's 'the NOx sensor.'
Why These Numbers Cross And What To Check
A0101531828 and its siblings EA0101531828/RA0101531828 are all Detroit Diesel's own numbering for the same physical sensor - E and R prefixes usually just denote a running change or reman designation, not a different part. Mallentech's N65208 and Bostech's NX1717708 are aftermarket-built units designed to bolt in and plug into the same harness connector, using the same 5WK9 7340A base sensor design underneath.
Where guys get burned is connector pin-out and thread length - these sensors thread into a boss in the exhaust stream and need to seat at the right depth to read accurately. A sensor that looks identical can have a slightly different probe length or a connector that's keyed differently for pre-SCR vs post-SCR position. Wrong spot, wrong readings, code comes right back.
Confirm by pulling the number off your old sensor or looking it up against your VIN before you order. If your old part reads anything close to what's in our interchange table, you're in good shape - but don't guess on pre vs post, check which port it came out of.
Ordering From PartStop
We keep these in stock in Tacoma and most orders headed anywhere in the Pacific Northwest go out same day. Rest of the country, it ships fast enough that you're not parking a truck over it for a week.
Every sensor we sell carries our 6+ month warranty, so if it's DOA or fails early it's not coming out of your pocket. We're not going to tell you it's a guaranteed fit sight unseen - cross-reference the number, and if you're not sure, call us with the old part in hand and we'll walk through it with you.
A0101531828 Cross-Reference & Interchange Numbers
These manufacturer and aftermarket numbers commonly cross-reference to A0101531828. 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 |
|---|---|
| Detroit Diesel (OEM) | EA0101531828, RA0101531828 |
| Mallentech | N65208 |
| Bostech | NX1717708 |
| Aftermarket | DDEA0101531828, A0101531828001 |
Frequently asked questions
Does A0101531828 fit my Freightliner Cascadia?
Depends on the year and which DD engine it's got, and whether you need the pre-SCR or post-SCR sensor. Pull the number off your old sensor or check your VIN - if it matches what's on our interchange list, it'll work, but don't assume without confirming.
Is this the same as the Bostech NX1717708?
It crosses over as a direct replacement built to the same 5WK9 7340A design, yes. Bostech isn't Detroit Diesel, it's an aftermarket manufacturer building to spec, so the physical sensor and connector should match, but always check your old part number against the table first.
Why do I have two NOx sensors and does it matter which one I order?
Yes, it matters. One sensor reads NOx going into the SCR system, the other reads it coming out after the DEF dosing does its job - that's how the ECM checks the system's actually working. They can look nearly identical, so match the number off the one you're replacing rather than guessing by position.
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.