How to replace a 3057 bulb, 3057 vs 3157

I just replaced a 3057 tail light bulb. I considered a 3157 since it has red LED’s, last longer, and looks really bright. Here are the issues. The 3057 filament bulb has two different filaments. The outer filament I measured at 800 ohms, the inner fatter, shorter filament I measured at 400 ohms. People replacing them have problems with the bases melting. The outer filament must go to the running lights, and the inner filament must go to the turn signal. The difference in a 180 degree turn. I noticed that someone said the turn signal circuit are the same value on the 3057 and the 3157, but the running lights are different. The guy at Autozone said he had a customer that replaced his 3057 with a 3157, and had problems with fuses burning out. An Alibaba vendor said to have an electrician make the installation, and some mentioned the addition of a new resistor to the circuit. I decided to stick with the original 3057K (krypton gas) now called a 3057LL (Long Life). I checked the turn signal to make sure it controlled the inner shorter fatter filament. You can put them into the sockets wrong, they are not keyed for correct installation. If you notice which side says Sylvania when you remove it, and install the replacement the same way,it should be OK.

1 Like

The bulb are reversable and the circuit remains the same.
the bulbs,3057, 3157, 3457, are interchangeable as well, the difference being the brightness.

When you mention LEDs…THAT changes things and we can only hope you don’t melt anything. I have not heard of meling LED 3157 but those silly blue headlights have melted plenty in our shop.

LEDs have poor side illumination so consider the scope of the viewing area of that lamp.
Straight back , fine, but if that same bulb is the one to be seen from the sides too…stick with incandescent.

Here’s a great site for more bulb information than you’ll ever need:

http://www.donsbulbs.com/cgi-bin/r/t.pl

I used the LED 3157 once, did not like them. The biggest issue I found is that the tail lights are quite bright, so bright that it was hard to tell when the brake lights were on. There was only a very small difference between the brightness of the two. Note: these were the LEDs commonly sold at places like AutoZone.

My son bought some LEDs for his car on line. They are called “SuperBright” LEDs and they seem to have a greater difference between the brightness of the tail lights and the brightness of the head lights so you can tell when the brakes have been applied at night.

The biggest advantage to LED brake lights is that they come on about 0.22 sec faster. Filaments have to get hot before they glow, LEDs come on full bright instantly. At 60 mph, that’s about 18’ of extra warning for the driver behind you. But considering the other issues of beam width etc, I’d suggest using them in the center light only.

Oh, so they (3057 bulbs) can go in either direction?
I wondered why there was no key to index the direction?

I doubt that Ken will see your post as he has not posted here since 2017.

Ok, I didn’t see the year.

You’re not alone. It’s easy to look at the “Jan '15” date and think it was Jan 15th. Many of us make that mistake.

Yeah, I thought it was this year.
So I guess those bulbs can go in either direction?

Oh…ok…I got you, January of 2015…

If you put them in wrong won’t the tail lights be brighter than the brake lights?

No. There is no “wrong way”. Notice how the contacts are offset? The same applies if you rotate the bulb 180 degrees, keeping the proper filament connected to the proper circuit.
image

Thank for the reminder, I have not had to replace a bulb in at least 15 years and I was thinking of the round brass base with the dual filaments that were high and low.

The only things I have had to replace on my 9 year old Camty are fluids and filters,brakes and tires and a windshield washer pump. My first car was 9 years old and I got it for $20 because the owner just had not gotten around to calling the junkyard. Cars have come a long way since then.

They were more interesting back then, today they are more like a kitchen or laundry appliance, we just use them and expect them to work.

Someone was complaining about a car burning a quart of oil every 2500 miles. In the old days, people did not go that far between oil changes. I remember when Kendall motor oil advertised itself as the 2000 mile oil. Doubling the recommendation at that time. Of course I remember people measuring the concentration of alcohol in the radiator and adding as needed. I also remember Farmers that thought that messing with alcohol for their once a week trip to town an unnecessary expense, they just drained the water when they parked it.