Packard Forum Index » V-8 (1955-56)

About 5 years ago I replaced the brake sending unit from the 3 to a 2 post unit and installed the necessary relay. Lately it takes a lot of foot pressure before the brake lights go on. I'm assuming it has something to do with the 2 post sending unit and not the relay. I've looked on-site here to see what P/N to get as a replacement, but to no avail. Does someone out there have any recommendations?

The Napa SL134 or its equivalent from the other parts stores is the regular and easily available 2 terminal switch most have used for years as replacements for the stock Packard switch from the early 40s onward.

The first 55-56 3 terminal switch aftermarket replacement was a Wells and then a VW switch for a time but both of those seem to have less than long lifespans. 15 or so years ago when the stock 3 terminal switch was really getting to be expensive and hard to find someone started making and selling the mod kit with the relay and regular switch and that has proven to be very successful.

Doubtful the relay is the issue but it is possible. More likely the switch is starting to fail so I would just get a replacement switch and go from there. If you are running silicone fluid that has proven to be very hard on all the hydraulic style switches. If that is the case maybe think about a mechanical conversion and of course, if you change the switch and still have issues it could be the BTV starting to act up.

Howard, thanks for your input. The Napa number sounds familiar and I think that is what I used. I don't have silicone fluid in the system. It would either be DOT 3 or 4.

The car stops great - it's the brake light so hoping it not the BTV.

The switch is an easy swap so I think I'll try that and go from there is it doesn't resolve the issue.

The switch took care of the problem