What This Thing Actually Is
The equalizer is the pivot piece that sits between your tandem axles on a Hendrickson walking beam setup, letting each axle articulate independently over uneven ground instead of transferring every bump straight into the frame. Wear one out and you'll feel it as clunking over dips, uneven tire wear, or the truck riding rougher than it used to.
This one's built for Hendrickson-equipped Chevrolet HD trucks from 2000 through current production, which covers a lot of trucks running the same basic rear suspension architecture over 25 model years. Hendrickson didn't change this design much because there was no reason to.
Why All These Numbers Point to the Same Part
3945816, S-25436, 25436, M89430, A89430, TDAM89430, and 508-30 all cross-reference because they're the same casting sold under different distributor and manufacturer part-numbering systems. Hendrickson uses M89430 as their base number, and the aftermarket suppliers who make compatible equalizers stamp their own SKUs on the box — but the physical part is the same bushing bore, pin diameter, and arm length.
Where guys get burned is assuming any equalizer with the right bore size will bolt in. It won't always. Check the bushing ID, the overall arm length between pivot points, and whether your application uses a straight or offset design — Hendrickson made minor variations on some capacity ratings. If your old part has any of the numbers in the cross-reference table stamped on it, you're good.
How to Actually Confirm Before You Order
Pull the number off your old equalizer if it's still legible — that's your fastest, most reliable check. Rust and grime eat those stampings over time, so if you can't read it, cross your truck's VIN against the Hendrickson suspension code on your build sheet or axle tag.
We keep this one in stock at the Tacoma counter and ship it nationwide same-day when you order before cutoff. It's aftermarket, not a Hendrickson-branded part, backed by our standard 6+ month warranty. If you're not sure it matches, call us with the numbers off the old part before you buy — costs nothing and saves a return shipping headache.
M89430 Cross-Reference & Interchange Numbers
These manufacturer and aftermarket numbers commonly cross-reference to M89430. 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 | 3945816, S-25436, 25436, TDAM89430, A89430, 508-30 |
Frequently asked questions
Does M89430 fit my 2015 Chevy 4500HD?
Likely, if it's running a Hendrickson walking beam rear suspension, but confirm by checking the number stamped on your existing equalizer or the suspension tag on the axle housing. Model year alone doesn't guarantee it since trim and GVWR packages can spec different suspension setups.
Is this the same as the S-25436 my parts book lists?
Yes — S-25436 and 25436 are the same physical equalizer as M89430, just numbered differently depending on which supplier catalog you're pulling from. The cross-reference table lists them together because they interchange directly.
How do I know if I need this or a bushing kit instead?
If the equalizer arm itself is cracked, worn oval at the bore, or the pin holes are elongated, you need the full equalizer. If the metal's still solid and it's just the rubber bushing that's shot, you might only need a bushing kit — pull the old part and inspect it before ordering.
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.