I just put a pair of these in the back of my W123 speedometer and they work great.

Search ebay for item number 111257427419

Seller is sanlongparts

No doubt other sellers have the same item.

These bulbs are called size T10

I have tried several others and they are not bright enough for my preference. These light up the speedometer, clock, and associated gauges bright enough to see but are not too bright to be distracting. It's been a long time since I've used the original bulbs but I'm pretty sure these are brighter. They are definitely whiter. I have been using some other LEDs for a few years but they are a little too dim for my preference.

I would recommend turning the brightness all the way up and leave it there. I had some LEDs fail a few years ago when I ran them with the brightness turned down. I don't know if that was coincidental or just bad LEDs. That was back when LEDs were new. Maybe they were just bad LEDs.

This is what they look like



Jim

I put LED's in my W123 dash a few years ago. For the "light tunnels" you refer to, I used ones w/ just face LED's since all you need is light shining forward. Made the speedometer much brighter than w/ the original incandescent bulbs. I don't notice the dimmer works much w/ the LED's, but I keep it on max anyway, which isn't too bright.

I also put LED's in the other dash positions, mostly for supposed longer life and negligible heat. They don't draw enough current to "boot-up" the alternator (mostly "BATT", but also from "low fuel" & "worn pads" in 1984+, I recall), but once I rev to >1000 rpm the alternator boots-up (from residual magnetism). I also noticed the "worn pads" LED lights faintly in heavy rain at night, but doesn't bother me.

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1984 & 1985 CA 300D's
1964 & 65 Mopar's - Valiant, Dart, Newport
1996 & 2002 Chrysler minivans

The fancier LED bulbs have voltage regulators built in-so the dimmer just makes them work harder to stay at full brightness

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Ya, for dash leds "simple" models are best... no regulation beyond a current limiting resistor, and no "can bus" load resistors to get hot.

-J

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1991 350SDL. 230,000 miles (new motor @ 150,000). Blown head gasket

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It's looking like these are plug in as one would replace the factory bulb. Correct?

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1986 300SDL 440,xxx

Yes, but they need correct polarity. If they don't work, turn them 180 degrees and try again.

Cool...I'll order a few up....thanks!

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1986 300SDL 440,xxx

Yes.

Someone a bit back was selling green LED speedo lights which are easier on the eyes and less distracting. I did this and am super happy with them.

This is how mine came out with LED's

Steve - what bulbs did you use? Were they a simple replacement for the original bulb? Thanks.

They were direct replacements with no modifications. I need to check what I used, I don't remember what I did yesterday and this was months ago when I did it.

That was me. Green is definitely the way to go. Much better contrast at night and easier on the eyes. I have more if anyone needs them.

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