What You're Actually Buying
This is a full kingpin kit for the Meritor FF941/FF961 front steer axle - kingpins, bushings, seals, thrust bearings, and the hardware to put it back together. It's not just a pin and a bushing in a bag; it's everything that wears out when a steer axle has 300,000+ miles of turning left and right on it.
These axles show up on a pile of different truck brands since Meritor supplied the axle assembly to multiple OEMs. Volvo used it, and it got badged with Volvo's own part numbers even though the axle underneath is straight Meritor. That's why you'll see FF941, FF961, and 70.961.12 all pointing at the same physical axle.
If your steering has slop in it, the truck wanders at highway speed, or you're hearing a knock in the front end on rough pavement, worn kingpins are usually the first thing to check before you start throwing money at tie rod ends or ball joints.
How the Cross Numbers Line Up
R203031 is the Meritor number and the one that'll be on the axle tag or in the Meritor parts book. 1115275S1 is a Volvo-specific number for the same kit - Volvo re-numbered a lot of Meritor axle parts when they spec'd them into their trucks, so you'll see this on Volvo-badged trucks even though it's the identical axle underneath. FF941, FF961, and 70.961.12 aren't part numbers so much as axle model/tag identifiers - they tell you which axle you're working on, not which kit box to grab, but they're how you confirm you're in the right ballpark before ordering.
308-299 and 460534ES are the aftermarket manufacturer numbers you'll see floating around from other suppliers packaging the same kit. Different box, same parts inside if it's built to the same spec.
Where this gets people: kingpin diameter and length aren't universal across every FF-series axle, and neither is the bushing bore. Before you order, pull the tag off your axle housing and match the number, or better yet pull the old kingpin and measure it. Don't go off truck year or model alone - axle suppliers got swapped around too much for that to be reliable.
Ordering From PartStop
We stock this kit here in Tacoma and it ships same-day if you're local or need it on a truck fast. Nationwide shipping if you're not close enough to walk in.
Every kit carries our 6+ month warranty, which covers you well past the point you'd know if something in the box was wrong.
Bottom line: confirm the number against your axle tag or the old kingpin before you order. We're not going to tell you it's guaranteed to bolt in sight-unseen - cross-reference gets you close, but the tag number is what closes the deal.
R203031 Cross-Reference & Interchange Numbers
These manufacturer and aftermarket numbers commonly cross-reference to R203031. 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 | 1115275S1, FF941, FF961, 70.961.12, 308-299, 460534ES |
Frequently asked questions
Does R203031 fit my Volvo VNL with a Meritor front axle?
Likely, if the axle tag reads FF941 or FF961 or shows 70.961.12. Volvo used this Meritor axle across a range of VNL years, but axle suppliers changed over model runs, so check the tag on the axle housing itself rather than assuming by truck year.
Is this the same as the 1115275S1 Volvo kit?
Yes - 1115275S1 is Volvo's own part number for the identical Meritor kit. Volvo re-numbers a lot of axle components for their parts system, but the physical parts and fitment are the same axle.
How do I know if I need the whole kingpin kit versus just bushings?
If you're pulling the axle apart at all, do the full kit - pins, bushings, seals, and thrust bearings wear together and replacing half of it just means you're back in there again in a year. Pull the old kingpin and check for scoring or play before you order to confirm you're dealing with kingpin wear and not something else in the steering linkage.
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.