In my notes, somebody on this or another forum had a cross-reference chart I believe from Grote. The Winnebago part number is 102520-01-000 (Your parts catalog:
2005 Winnebago Adventurer WPG38J)
Supposedly --and I don't have it in front of me-- the cross-reference chart for that part from Grote and Truck-Lite are as follows:
Grote:
47063 SuperNovaŽ Flush-Mount LED Cab Marker Light
Truck-Lite:
25250Y 25 Series, LED, Yellow Rectangular, 3 Diode, Marker Clearance Light
The outside dimensions are slightly different but the important thing is that the cut-out and screw hole spacing will (or should, take a measurement) match the Winnebago OEM fixture.
I'll attach the measurements below for each.
HERE is the Grote through Amazon
HERE is the Truck-Lite through Amazon
The reason these are rather expensive as that they are LED. You may be able to find incandescent ones for a much lower cost. I can check for you if you'd like should you want to replace what you have with a similar incandescent fixture.
You can shop around online to see if you can find a better deal, however.
There also could be some other manufacturers like Petersen, RV Designer, or Optronics that could have similar replacement possibilities but I can take a look later if you find that the ones above will not work.
eta: also, Winnebago gas Class A coaches around that time frame had a lot of problems with the OEM fixtures of not only getting water inside the fixture itself but also the manner in which they are mounted (a steel plate under the fiberglass?...can't remember the issue exactly) had issues with rusting. So you may want to inspect the mounting holes and take precaution to prevent water getting through the screw holes.
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