Cab light question

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midwest

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Any way to find the thread size on the bolts that hold the cover to the housing on these Deitz lights? I went to put the covers back on and they weren't screwing in. I looked and all the bolts are stripped at the end. Whenever they were put on, wrong size bolts must have been forced in and like I said above the covers haven't been off the lights for years. They are pretty fine thread bolts.
 

midwest

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So after a year of looking at the cab lights I finally decided today to mess with them. As expected was a ground issue. I got a scrap wire and ran it from a ground to each light and they all lit up (except for one). The bulb was bad in that one, but I still think it has an issue (which is probably just needing cleaned). One of the sockets has 12 volts when touched with the test light but still doesn't light up with the bulb in it. I'm going to clean out the inside of the socket real good tomorrow and see if that fixes it. On the other lights there was some rust on the screws where they go through the roof. I put new scres in each one and they started working again.
 

midwest

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Ok, so stupid question of the day. I went today to get new bulbs just to replace them all. Was kind of shocked to see there was about 8 different varieties of bulbs that had the same end on them. The single "knob" on the end and the two ears/nipples on the side. All had slightly different variations of volts and wattages. cant remember the exact numbers but anywhere from 11 volts and 7.5 watts to 13 volts and 9 watts. Of course when I asked the local "expert" what the difference was he said they are all exactly the same. I said seems weird they would all have different model numbers and specs if they were exactly the same. He said just grab any of them...
Anyway, will any of these bulbs technically light up and work or do I need to grab a specific one.
 

RustyPile

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You're making this hard on yourself, and that clueless counter person isn't helping the situation... Take one of the old bulbs that work with you to the parts place. Look closely at the base of the old bulb, a part number should be there. If not, simply match the bulb to what the clueless counter person has in stock.. Any and all bulbs on your truck are 12 volts with varying wattage/brightness and physical size..
 

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@RustyPile is right. There may be 8 different varieties of bulbs that have the same end on them but, 1 and only 1 is right for your application.
 

Turbo4whl

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@midwest Scott, # 67 bulb is what those lights would have from new.

On a side note, many old trucks (tractor trailers) would be upfitted with a bulb just like the #67, but it had two filaments in the globe. This way if the first filament burnt out, the second filament, with a higher resistance would light.

I believe this was to thwart out the road patrols who were just looking for a reason to stop the semi's rolling through their borough. (Old history)
 

midwest

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Thanks for the info. Rusty and Snoots. This is why I asked in the first place. The options I mentioned above were just the bulbs that were the same physical size and design, and none of them said 12 volts. They had a ton of other options that were physically different. For example the #67 mentioned above says 13.5 volts.
 

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Thanks for the info. Rusty and Snoots. This is why I asked in the first place. The options I mentioned above were just the bulbs that were the same physical size and design, and none of them said 12 volts. They had a ton of other options that were physically different. For example the #67 mentioned above says 13.5 volts.
I guess the "politically correct" term would be nominal 12 volts.. A fully charged automotive battery registers 12.5 volts.. A properly working charging system will register between 13.8 and 14.3 volts.. Back in the daze, all bulbs were marked "12 volts".. These days, something got lost in the translation when the Chinese and other off-shore manufacturers entered the game.

Bulbs within the above mentioned voltage range will work. My best guess is #67 is what you need. As others will attest, expect poor quality from anything except Sylvania, GE, Wagner, and maybe a couple other Made in USA brands..
 

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Different wattages for different pn's, although all are 12v. My 1982 Harley Davidson has a tiny bulb for the fuel gauge but it's only like a 2 watt bulb, so I always try to replace it with a bit brighter bulb. Those tiny elements don't like the vibration of an HD for some reason, especially since they're made in Asia these days!
 

HotRodPC

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Those "ears" doesn't matter, you can replace the ones that have "ears" and flat ends with some stiching out wire with the ones that have no "ears" and pointy ends. Wattage is also not that critical, you won't get a bulb that has more than 10 W. Just make sure that the length is fine
 

Turbo4whl

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Bulbs within the above mentioned voltage range will work. My best guess is #67 is what you need. As others will attest, expect poor quality from anything except Sylvania, GE, Wagner, and maybe a couple other Made in USA brands..


:popcorn: I am sure my reply was overlooked. Must have been because of my side note.

The correct bulb for that ID lamp is #67.

This is not a guess.
 

midwest

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Turbo, I did not overlook your response and I’m the one it matters to in this specific thread…Thanks again
 

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:popcorn: I am sure my reply was overlooked. Must have been because of my side note.

The correct bulb for that ID lamp is #67.

This is not a guess.
Well, don't be so sure... If you're intent is to be snotty, I'm not sure why, as I was agreeing with you.. So I'll just reply with :shrug:
 

Turbo4whl

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Well, don't be so sure... If you're intent is to be snotty, I'm not sure why, as I was agreeing with you.. So I'll just reply with :shrug:
No, your reply seemed as though you were not sure. I wasn't sure the OP, Scott saw my post. Now I know he has, and not my intent to be snotty.
 

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