The 1141LL's that are in Norm's trailer are a low power version of a standard 1156 automotive bulb. Both bulbs look like this:
They are both standard BA-15 base bulbs. The main metal shaft of the bulb base is 15 mm (.59") in diameter.
There are several other automotive bulbs which have the same base and varying power levels. There are now a bunch of LED versions out that consume much less power and give off about the same amount of light.
If your local auto parts store can't help you with a standard item like an 1141 or 1156 bulb, it really is time to find another auto parts store that will help you.
Sunline1, it would be very helpful if you could pull one of the bulbs and give us the part number off the base and any other info that would help identify it. Your bulb may not be an 1141 like Norm's and if you really want some help in finding a replacement, let's make sure we've properly identified your bulb first.
FWIW, most RV's use either T-3, T-13, BA-15, or festoon base bulbs for interior lighting. Replacements can usually be found in almost any auto parts store, and there are now a wide range of LED replacements available on the internet and eBay.
'12 F250 4x4 Super Duty PowerStroke 6.7 diesel
2011 to present: '11 Cougar 326MKS
1999 to 2011: '99 Sunline T-2453
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