What this belt is and where it lives
This is the main accessory drive belt on the MT35 chassis — runs your alternator, power steering pump, and AC compressor off one continuous loop. It's an 8-rib belt (8PK) at 1365mm length, which is what the 01-23415-004 number tells you if you know the code.
MT35 used this belt straight through the 97-01 build with no changes we've seen. If your MT35 falls outside that range, or you've had pulleys swapped, pull the old belt and check the length/rib count stamped on the backside before ordering.
Why these numbers cross and what to double-check
8PK1365 is the actual belt spec — 8 ribs, 1365mm effective length. Freightliner's 01-23415-004 and Mercedes' 815.4080535 are the same belt under different parts systems since a lot of that era's drivetrain componentry shares lineage. Dayco's 5080537 and Gates' K080537 are both aftermarket versions built to that same 8PK1365 spec, and World Truck's F02942S266 crosses in too.
Serpentine belts are simpler than most cross-refs — no spline count or bolt pattern to worry about, just length and rib count. Where guys get burned is a stretched or previously-swapped belt giving a false reading, or a pulley replacement that changed the routing length slightly. If the number on your old belt matches anything in our table, or you can confirm 8PK1365 stamped on it, you're good. When in doubt, give us the VIN and we'll pull it by chassis.
Ordering from PartStop
We keep 8PK1365 belts in stock at the Tacoma counter — if you're local, swing by same-day. Otherwise it ships out that day to anywhere in the lower 48.
$19.99, and it carries our 6+ month warranty. Cheap enough that if you're on the fence about belt condition, just replace it — better than a tow call because a stretched belt let go on you at 2am somewhere between Tacoma and Portland.
0123415004 Cross-Reference & Interchange Numbers
These manufacturer and aftermarket numbers commonly cross-reference to 0123415004. 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 |
|---|---|
| World Truck | F02942S266 |
| Dayco | 5080537 |
| Gates | K080537 |
Frequently asked questions
Does 01-23415-004 fit my MT35?
If it's a 97-01 MT35, yes, that's the number for it. Still worth checking the belt you're pulling off — if someone did a pulley swap down the line the length could be different. Give us the VIN and we'll confirm off the chassis build.
Is this the same as the Gates K080537?
Same spec belt, yes — both are 8PK1365, just packaged under Gates versus what we've got in stock. Interchanges directly, no difference in fitment.
Belt looks fine but has some cracking, do I need to replace it now?
Surface cracking across the ribs is normal wear and not urgent by itself, but if you see chunks missing or it's glazed and shiny, that's slip risk — replace it before it strands you. At twenty bucks it's not worth nursing along.
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.