What You're Actually Buying
This is a sealed LED oval, red lens, 12V, sized for the standard 6-3/8 inch oval grommet mount that's been the trailer industry standard for decades. It handles brake, turn, and tail functions off the same three-wire hookup most trailers already run, so it's not a re-wire job — it's a swap.
It comes with the grommet included, which matters more than people think. A tired or torn grommet is half the reason lights fail in the first place — water gets in behind a good LED and cooks the board just the same as it would an old incandescent bulb.
This isn't a specialty light. It's the light you'll find on van trailers, reefers, flatbeds, and plenty of straight trucks — basically anywhere a builder needed a compact, DOT-legal rear light in the 6-3/8 oval footprint.
Why These Numbers Cross
The OE reference F01820S125 and the Grote 54172 land in the same interchange group as our PS-EL.01.UN.012 because they're built to the same oval footprint, same grommet mount, and same red lens/brake-turn-tail function. Manufacturers across the industry standardized this shape a long time ago so trailer builders wouldn't be locked into one supplier.
Where you can get burned is wire count and connector style — some ovals run a different pigtail length or a different plug end even though the lens and mount are identical. LED versions also draw less current than old incandescent ovals, which is fine electrically but can occasionally trip a bulb-out warning on trucks with older monitoring systems.
Surest way to confirm: pull the old light and read whatever number is molded into the lens or printed on the label, or check what your trailer builder spec'd by VIN/build sheet. If that number isn't one of the three above, call us with it — cross-referencing an oval lamp takes five minutes on the phone.
Buying It From Us
We keep these in stock at the Tacoma counter, so if you're broke down local or just doing PM on a batch of trailers, you can grab it same-day. Mail order ships nationwide, and it's a light — it travels fine in a small box, no freight nonsense.
Backed by our standard 6+ month warranty. If it fails outside of you backing into a dock plate with it, we'll make it right.
One light or a case of them for a fleet PM run, doesn't matter — pricing and stock hold either way.
PS-EL.01.UN.012 Cross-Reference & Interchange Numbers
These manufacturer and aftermarket numbers commonly cross-reference to PS-EL.01.UN.012. 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 |
|---|---|
| OE | F01820S125 |
| Grote | 54172 |
Frequently asked questions
Does F01820S125 fit my trailer?
Probably, if your trailer takes a 6-3/8 oval red brake/turn/tail light with a grommet mount — that's the vast majority of vans and reefers built in the last 20-plus years. But confirm off the number stamped on your old light or your build sheet before you order, since oval-shaped lights aren't all wired the same underneath.
Is this the same as the Grote 54172?
It cross-references to it — same oval shape, same grommet mount, same brake-turn-tail function in red. Grote didn't invent the oval shape, they just build to the same industry-standard footprint everyone else does. Check your old light's part number to be sure it's an apples-to-apples swap on wiring.
Can I use this to replace an incandescent oval with LED?
Yes, that's the most common reason customers ask about this one. LED draws way less amperage, runs cooler, and lasts a lot longer than the old bulb-style ovals. Just double check your trailer's brake controller or any lighting monitor isn't picky about the lower LED draw — most modern setups don't care, but it's worth a quick look if you've got an older module.
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.