Anyone know what bulb to use for the gauges on the left hand side? One is the gas gauge and the other is coolant temp. Everything online says either 194 or 161, but the stock bulb is smaller. My '98 Explorer takes 194s but either something changed in '99 or Mercury just had to be different. The auto parts guys don't know. It looks like a 37, 73 or 74 might work, but it's hard to tell with the bulbs still in the package. Auto parts guy says the difference between the three is that they're different wattage so I don't want to cook anything in the instrument panel.

The stock bulb has some markings but doesn't match anything I've seen and I'm not sure of some of the letters or numbers. It looks like NH8 on the top line and 1M or /M or maybe 7M without the horizontal part of 7 (i.e., incomplete marking). Searching on that didn't produce any hits.

The owner's manual doesn't provide a bulb number.

 

Grainger seems to think the 74 bulb is the appropriate fit for a Ford instrument panel bulb.

-Rod

 

Hmm. Thanks. I never considered Grainger. I've bought other stuff from them before but not anything automotive.

 

Well, I did a little more online research and found that the 37 was half way between the 74 and the 73 in terms of wattage. So, that's what I bought. When I pulled the instrument cluster out, I took all of the bulbs out and found some that had complete markings on them. As it turns out, they were 37s. Better to be lucky than good...

The bulb cavity is quite big and the wattage on the bulbs is so low that I probably could have used 74s without the additional heat causing any issues. There's only about 0.3 watts difference between the bulb with the lowest wattage and the bulb with the most wattage.

 

Thank you for following up with confirmation on what the original bulb likely is. Going with the 74 possibly would have made some of those gauges excessively bright relative to the dials, so it's a good thing you went with the 37.

-Rod