What This Panel Does
The under-step door fairing panel mounts below the passenger door, outboard of the step box, and closes out the lower side of the cab. It is part of the truck's lower fairing system, not a structural member. Its job is to carry the body line from the door down past the step and keep the airflow attached along the side of the cab.
Because it sits low and forward of the drive tires, this panel eats everything the road throws up. Slush, salt spray, gravel, curb strikes, and the occasional dock bumper. It is also the first thing a driver's boot catches when he swings down off the step in a hurry.
A33-1255-200R is the right-hand, passenger-side panel. Left and right are not interchangeable. Confirm you are ordering for the correct side before you commit, and check the number molded or tagged on the old panel if it is still readable.
Why These Numbers Cross
A33-1255-200R and A33-1255-100R describe the same under-step door fairing position on the passenger side of the T680 Next Gen cab. The shared A33-1255 root is the part family for this fairing location; the trailing block separates revisions and sourcing within that family. Both land in the same mounting footprint below the passenger door and step.
That means a truck tagged with the earlier number and a truck tagged with the later one are both looking for a panel with the same body line, same cutouts, and same fastener pattern around the step area. The numbers cross for identification, which is why a search on one pulls up the other.
A33-1255-100R is listed here for identification only. PartStop is not affiliated with, endorsed by, or authorized by Kenworth or PACCAR, and listing their number does not imply any relationship. This cross-reference is a starting point. Confirm fitment by VIN or by reading the number off the panel you are replacing.
Check Before You Order
Pull the damaged panel first if you can. Look at the mounting tabs and the brackets behind it. A panel that failed from a curb strike usually takes a bracket or two with it, and bolting a new panel to a bent bracket will crack the new one in short order. Straighten or replace the hardware while the area is open.
Inspect the fastener holes and any push-rivet locations. Elongated holes mean the panel has been working loose and flexing, which is how most of these crack in the first place. Note the side, left or right, and verify the VIN against the model year range before placing the order.
A33-1255-200R Cross-Reference & Interchange Numbers
These manufacturer and aftermarket numbers commonly cross-reference to A33-1255-200R. 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/Cross-Ref | A33-1255-100R |
Frequently asked questions
Will A33-1255-200R fit if my old panel is marked A33-1255-100R?
Those two numbers cross to the same passenger-side under-step fairing position on the T680 Next Gen. The cross-reference is a starting point, not a fitment guarantee. Verify by VIN or by matching the mounting pattern on the panel you pulled off before you install.
Is this panel the same for driver and passenger side?
No. A33-1255-200R is the right-hand, passenger-side panel only. The left and right panels mirror each other and will not swap. Confirm which side you need before ordering, since a wrong-side panel will not line up with the step or the door body line.
Is this an original Kenworth part?
No. This is an aftermarket direct replacement manufactured by Changzhou Yijiang Auto Parts Co., Ltd. Any Kenworth or PACCAR numbers shown are listed for identification purposes only. PartStop is not affiliated with or authorized by those manufacturers.
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