What You're Actually Buying
This is a 16.5-inch diameter, 5-inch wide brake drum for the steer axle, not the drive axle — 10 bolt holes, 11.25" outboard mounting configuration. That outboard spec matters because steer drums and drive drums on the same truck can look similar but won't interchange if the mount depth is off.
It's built for HD applications — the kind of steer axle you'd see on a heavier Class 8 truck, not a light-duty pickup or delivery van. Weight rating and hub design are what dictate whether this drum bolts up.
Bottom line: measure your old drum or read the casting number before you order. 16.5x5 with 10 bolts is a common config but there's more than one variant out there.
Why All These Numbers Cross
3598X is the number most counters recognize first, but Gunite made this same drum under GUN3598X, GUN3598BX, and 3758X — different casting runs, same physical part. Webb's version shows up as 65151B20 or 65151B, and ConMet's is CV71063 or 107453/10005332. Meritor's cross is 123589.
These all cross because the drum dimensions — bolt circle, mounting depth, drum diameter and width — are identical across manufacturers for this application. What doesn't always match is casting quality, balance, and sometimes minor tolerance stack-up, which is why we tell guys to check fitment before installing, not just match a number off a parts book.
Watch out for suffix letters — an 'X' or 'B' at the end of a casting number sometimes denotes a minor revision. Usually doesn't affect fit, but if you're chasing a warranty claim or a batch issue, that letter is how the manufacturer tracks it.
Ordering From PartStop
We're in Tacoma, so if you're a local fleet or owner-op, same-day pickup is usually doable if we've got it on the shelf — call ahead so we can pull it before you drive over. Nationwide shipping runs regular for outside the PNW.
Every drum comes with the standard 6+ month warranty. Doesn't matter how good the cross-reference looks on paper — before you order, pull the number off your old drum or check your VIN against the axle spec. Steer axle parts are not the place to guess.
3598X Cross-Reference & Interchange Numbers
These manufacturer and aftermarket numbers commonly cross-reference to 3598X. 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 |
|---|---|
| GUNITE | GUN3598X, GUN3598BX, 3758X |
| WEBB | 65151B20, 65151B |
| CONMET | 107453, 10005332 |
| MERITOR | 123589 |
| ConMet | CV71063 |
Frequently asked questions
Does 3598X fit my truck?
Depends on your steer axle spec, not just the make of truck. Confirm by reading the casting number on your old drum or checking your VIN against the axle build sheet. 16.5x5 with 10-bolt, 11.25" outboard is a common HD steer config but there are close variants that won't bolt up.
Is this the same as the ConMet CV71063?
Yes, CV71063 is ConMet's number for this same 16.5x5 steer drum — it crosses directly with 3598X. Same mounting spec, same drum size. We'd still recommend matching against your old part's number if you're not sure which application you've got.
Why does Gunite have three different numbers for what's supposedly the same drum?
3598X, GUN3598X, GUN3598BX and 3758X are casting variants from different production runs — normal for Gunite. Physically they're the same drum for fitment purposes. If you're doing a warranty claim, keep track of which exact number was on your original part.
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.