Several weeks ago Wayne Midkiff asked a question regarding brake hoses. His question was in regards to when Corvettes stopped using the c-clip retainer on the fitting on the frame end of the hoses. I responded that the only brake hoses that I was aware of that used c-clips were aftermarket hoses and if Corvettes ever used them as original equipment, that ended after the 1966 model year. Well, that information was correct but, as a result of some further research, digging into my NOS parts collection and the acquisition of some other NOS parts, I can now add something to the story.
From 1963 until 1982 Corvettes used 4 different GM part number front brake hoses and 4 different part numbered rear brake hoses. From 1963 through 1966, Corvettes used GM #3770240-front and GM #3826352-rear. From 1967 through 1974 the GM part numbers were #3898231-front and #3878958-rear. For 1975, from start of production until about 3/75, Corvettes used GM# 351549-front and GM# 351550-rear. From 3/75 until the end of C3 production in 1982, the part numbers were GM# 357793-front and #357794-rear.
I now have several NOS examples of each of these hoses in my collection. I will attempt to briefly describe the differences in configuration. All of the front hoses are 14" overall length and rear hoses are 8-3/4" overall length. Although there were the 4 different sets of hoses used for the specific model years described above, all are functionally interchangeable and the final iteration, #357793/357794, service all 63-82 applications and continue to be available in service. For the sake of brevity, I am going to describe only the front hoses, but the rears are similar in configuration for the particular "set".
The 63-66 front brake hose, GM #3770240, has the end fittings attached with long, gradual crimps. The frame end fittings HAVE A C-CLIP TYPE RETAINER, as Wayne Midkiff described. The brake cylinder/caliper end fitting has an unusual turned-down, machined area between the hex surface and the threaded end with a blue inspection mark seen on the crimp area of this end. The fittings are cad or zinc plated with a very light, dull dichromate finish. The black hoses have a very light yellow or off-white stripe running the full length with no alpha numeric markings of any kind.
The 67-74 front brake hose, GM #3898231, has similar, but slightly shorter, crimped areas on both end fittings. The frame end fitting does not have a c-clip retainer but, instead, uses an integral retaining flange. The caliper end fitting has no turned down area and, instead, has an 1-1/8" long hex. What appears to be a manufacturers' logo is repeated for the full length of one surface of the hex. The fittings are cad or zinc plated with a dichromate finish which is somewhat brighter than the earlier hose fittings. The black hoses have broken red lines running the entire length and "SAE 40R1" and "AV-1/8-8396" marked intermittently.
The early 1975 hose, GM #351549, is quite rare as it was used for such a short period. The end fittings have crimps very similar to the 3898231 hose, but slightly "deeper". The frame end fitting also has the integral retaining flange like the 3898231 hose. However, the caliper end fitting has the turned down, machined area like the 3770240 hose, the difference being that the remaining hex portion of the fitting is shorter than the 3770240 fitting. The hex fitting has the number "1502" stamped in small characters on one side and an unreadable manufacturers' logo on the other side. The fittings are zinc or cad plated and there is NO dichromate finish. Both of the hoses that I have show no markings or stripes whatsoever on the black hose, but, it is possible that these have faded out.
The mid-75 until 1982 hose, GM #357793, has short, deep crimps on both fittings. The frame end fitting has the integral retaining flange. The caliper end fitting has the 1-1/8" long hex, similar to the 3898231 hose and has the inscription "5157y" with the manufactures' logo, a stylized "W", stamped into it in very small characters. Both fittings are zinc plated with a very bright dichromate finish. The black hoses have short, white line segments and the inscriptions "DOT-AV-08-1/8-HL" and "AV-3.2-8870-U8216".
From 1963 until 1982 Corvettes used 4 different GM part number front brake hoses and 4 different part numbered rear brake hoses. From 1963 through 1966, Corvettes used GM #3770240-front and GM #3826352-rear. From 1967 through 1974 the GM part numbers were #3898231-front and #3878958-rear. For 1975, from start of production until about 3/75, Corvettes used GM# 351549-front and GM# 351550-rear. From 3/75 until the end of C3 production in 1982, the part numbers were GM# 357793-front and #357794-rear.
I now have several NOS examples of each of these hoses in my collection. I will attempt to briefly describe the differences in configuration. All of the front hoses are 14" overall length and rear hoses are 8-3/4" overall length. Although there were the 4 different sets of hoses used for the specific model years described above, all are functionally interchangeable and the final iteration, #357793/357794, service all 63-82 applications and continue to be available in service. For the sake of brevity, I am going to describe only the front hoses, but the rears are similar in configuration for the particular "set".
The 63-66 front brake hose, GM #3770240, has the end fittings attached with long, gradual crimps. The frame end fittings HAVE A C-CLIP TYPE RETAINER, as Wayne Midkiff described. The brake cylinder/caliper end fitting has an unusual turned-down, machined area between the hex surface and the threaded end with a blue inspection mark seen on the crimp area of this end. The fittings are cad or zinc plated with a very light, dull dichromate finish. The black hoses have a very light yellow or off-white stripe running the full length with no alpha numeric markings of any kind.
The 67-74 front brake hose, GM #3898231, has similar, but slightly shorter, crimped areas on both end fittings. The frame end fitting does not have a c-clip retainer but, instead, uses an integral retaining flange. The caliper end fitting has no turned down area and, instead, has an 1-1/8" long hex. What appears to be a manufacturers' logo is repeated for the full length of one surface of the hex. The fittings are cad or zinc plated with a dichromate finish which is somewhat brighter than the earlier hose fittings. The black hoses have broken red lines running the entire length and "SAE 40R1" and "AV-1/8-8396" marked intermittently.
The early 1975 hose, GM #351549, is quite rare as it was used for such a short period. The end fittings have crimps very similar to the 3898231 hose, but slightly "deeper". The frame end fitting also has the integral retaining flange like the 3898231 hose. However, the caliper end fitting has the turned down, machined area like the 3770240 hose, the difference being that the remaining hex portion of the fitting is shorter than the 3770240 fitting. The hex fitting has the number "1502" stamped in small characters on one side and an unreadable manufacturers' logo on the other side. The fittings are zinc or cad plated and there is NO dichromate finish. Both of the hoses that I have show no markings or stripes whatsoever on the black hose, but, it is possible that these have faded out.
The mid-75 until 1982 hose, GM #357793, has short, deep crimps on both fittings. The frame end fitting has the integral retaining flange. The caliper end fitting has the 1-1/8" long hex, similar to the 3898231 hose and has the inscription "5157y" with the manufactures' logo, a stylized "W", stamped into it in very small characters. Both fittings are zinc plated with a very bright dichromate finish. The black hoses have short, white line segments and the inscriptions "DOT-AV-08-1/8-HL" and "AV-3.2-8870-U8216".
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