New owner wedge base bulb question

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Active member
Jul 24, 2018
Hello all,

  New owner getting my toy hauler ready for a long-term work/travel journey.  One of the first items is to swap out the halogens for LED, both for the energy and the heat savings.  I have wedge based bulbs, pulled a couple and they are clearly stamped 921 (manual confirms) but are T5 bulb size 5/8".  All LED replacements details under 921 say T10.  I have been (shockingly) unable to find any clear articles or videos that state whether or not the wedge base of a T5 is the same as a T10, all they talk about is bulb size.  Are the wedge bases the same?  Then I just need to determine if the overall LED bulb size, which are usually smaller, will fit in the housings.  Figured I would ask here first before making a store trip to compare them.
I bought my bulbs from M4 Products. So far, from the tiny aisle lights, to LED tubes, to wedges and globes, they've been able to fit every application with a choice of warm, daylight or cool colors. Definitely not the cheapest, but good customer service and the one time I had a bulb fail they replaced it without question
As I understand it, in wedge base bulbs, the Txx designation does not pertain to the base. They are all a 5 mm wedge base that fits into the 5 mm socket.  The xx refers to the width of the bulb body, basically the maximum width of the bulb itself.  That would mean that a T5 and a T10 have the exact same base, but the T10 is twice as wide in the body.  That may or may not physically fit in the fixture, but electrically it should plug right in.
Thank you Gary.  I did grab a few tonight and that appears to be correct.
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