57-early 58 gas caps vs pass cars

[Brad H.]

What are the visual differences between the early 58 gas cap (flat top with square protrusion in center) vs the passenger car cap, do they all say eaton inside or are some an SM logo, I want it right. Thanks, Brad.

[Mike G.]

Re: 57-early 58 gas caps vs pass cars

completely different cap. the eaton caps you are describing are 57 58 corvette only. there was an eaton cap made around the same time that was for a marine application. they look exactly the same except the marine caps have a small loop inside to hook a chain. if it has the loop it is NOT a corvette cap. eaton also made a cap that looks close to the correct cap but where the square rivet sits the area around it is slightly sunken and not raised like the correct cap. i will post a pic of both. the first is correct the second is not.

[Mike G.]

Re: 57-early 58 gas caps vs pass cars

here is a pic of the correct bottom without the loop. i can take a pic of the loop if anyone wants. i have 4 or 5 of these caps in my collection.

[Gary C.]

Re: 57-early 58 gas caps vs pass cars

Mike, Eaton also made caps identical to the 57-E58 except the steps were concave instead of raised. Have several in my collection. Gary....

[Brad H.]

Re: 57-early 58 gas caps vs pass cars

Now I am confused, will both pass ncrs judging, looks like the book shows the raised and not the sunken, the one I am looking at is sunken but has an SM stamped inside and not Eaton, is that right, would like to see the looped one for chain. Thanks, Brad.

[Bob M.]

Re: 57-early 58 gas caps vs pass cars

How can you tell it is an Eaton cap if there is no makers mark. The JM does not say that the 58 cap was made by Eaton, but said who the makers are of the other four. I don't see a logo on the ears on the inside of the one on the right to say it is an Eaton cap. There is one on fleabay now that has a starting bid of $500 and he states it is an Eaton cap.

[Mike G.]

Re: 57-early 58 gas caps vs pass cars

the only correct cap that will pass judging is the eaton cap with the raised center. it does have an eaton logo on the underside of the cap. I looked through my caps and found one with the loop. the top of the cap is identical but the loop is to hook a chain for marine use. in the other pic the 4 caps on the right are correct. the two on the left( sunken center) are not correct for any year corvette. people put these on ebay all the time calling them corvette gas caps, they are not.

[Joe M.]

Re: 57-early 58 gas caps vs pass cars

i made the mistake of purchasing a NOS Stant gas cap for a 1960-1961 Oldsmobile passenger car even though the vendor said it would not fit. The outward appearance is the same, but the diameter of passenger car gas cap is smaller than the Vette gas cap; wasted $30 (probably the smallest $$ I have wasted on my 1960!). I was told that there was GM internal competition between engineers of the different car lines. Therefore, the Oldsmobile gas cap would not fit any other GM car or truck. In my case, I know this to be true. Need a NOS Olds gas cap?