Are all 4 of the tail light bulbs on the 72 Cutlass 1157 's. Mine are old and corroded and I can't make out the numbers on them.

 

Yes. Make sure the contacts are free and they spring back when depressed. If not, the lights won't work properly. Mine were a mess when I bought the car and required a lot of playing with to get them to work.

 

1156-single filament
1157-double

 

I've found that the 1157A 's are brighter at all four corners of the car.

 

I've seen those, I used to think the "A" stood for amber, but now I guess they came out with the new Siver star series that are 27w. I'll have to try those.

 

You used to think? You would be correct to still think that. The A does stand for the amber tinted glass on the bulb. I don't like silver star bulbs. Tried em, didn't like em.

 

Be very careful when installing bulbs of higher wattage than stock. I've seen too many melted lenses from this.

 

Thanks for the info guys. I used 1157's for all four. The sockets and springs were a mess but all four are working. Now I see that Old Cutlass says to use 1156's on the top, 1157's on the bottom. Who is correct?

 

Since the retaining pins of the 1157s are staggered and the pins on the 1156s are level, only one type should fit, but, just in case, the sockets with one contact are for 1156s, the sockets with two contacts are for 1157s.

- Eric

 

You are reading his post wrong. All he's saying is 1156 bulbs have only 1 terminal at the base and 1157 bulbs have 2.

Since you need to have the tail lights work as 'running lights' and 'brake/signal' lights you need 1157's. When Eric gets around to looking at this again I'm sure he'll say the same thing. Anyway - 1157 or 1157A's will do the trick.

IF by chance you made a mistake and put 1156 bulbs in? The bulb would burn bright ALL the time and your signals wouldn't work either.

 

What Allan said is what I meant. I was explaining what the difference was between the two if you could not read the number. All you would have to do is look at the bulb.