What This Valve Does and Where It Lives
The ABS modulator sits between your brake chamber and the air supply, and it's what lets the ABS controller cycle air pressure to a wheel end during a stop when the wheel speed sensor sees a lockup coming. On these trucks you'll usually find one per drive axle wheel end, sometimes on steer too depending on how the truck was spec'd.
This is a Wabco-designed unit, so it shows up across brands because Volvo, Freightliner, and Peterbilt all sourced Wabco ABS components for a lot of their build years. Doesn't matter what badge is on the hood - if the truck came with a Wabco system, the modulator part number is what matters, not the truck brand.
Why All These Numbers Cross
4006110030 is the Wabco number stamped on the housing. R955356 and R955356NX are Meritor's version of stocking that same part - Meritor buys Wabco valves and puts their own part number on the box for their dealer network. Same valve, different label.
The other Wabco numbers in the table (4721950790, 4725001230, and the rest) are related modulator variants - same family, similar function, but not always interchangeable pin-for-pin depending on port configuration or which axle position they're built for. Before you order, pull the number off the old modulator itself - it's stamped right on the housing - and match it against what's listed. Don't go by truck year or model alone, because two trucks off the same line can have different valve numbers depending on how the ABS was spec'd.
Ordering From PartStop
We keep this one in stock in Tacoma, so if you're local and your truck's down, same-day pickup is usually doable - call ahead so we can pull it before you drive over. If you're not in the area we ship nationwide, and most orders move fast because ABS modulators are a common failure point and we know trucks don't sit well.
Comes with our 6+ month warranty. If you're not 100% sure this is your part, send us a photo of the number stamped on the old valve before you buy - saves everybody a return shipment.
4006110030 Cross-Reference & Interchange Numbers
These manufacturer and aftermarket numbers commonly cross-reference to 4006110030. 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 |
|---|---|
| Cross-Reference | R955356, WABCO 4006110030, R955356NX, 6650A |
| Wabco | 4721950790, 4725001230, 4725001220, 4725002220, 4725002230, 4725002260, 4725005220, 4725005250, 4725005230 |
| Anythingtruck/SKU | 650-R955356 |
Frequently asked questions
Does 4006110030 fit my Freightliner?
Likely, if your truck runs a Wabco ABS system, but confirm by pulling the number off your old modulator or checking your VIN build sheet. Freightliners spanned a lot of build years and ABS suppliers, so don't assume by truck model alone.
Is this the same as Meritor R955356?
Yes - R955356 is Meritor's part number for the same Wabco-built valve. Different label, same physical part. R955356NX is the same thing, just a different revision or packaging suffix Meritor used.
How do I know if this is the right modulator for my specific axle position?
Check the number stamped on the housing of the one you're replacing. Modulators can differ by axle position even on the same truck, so matching your old part's number is more reliable than going off truck make and model.
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.