David Johnson

Thanks for the advise everyone. I will get the Model number as soon as I can. I am new to the shop and just get bits and pieces of info. I am a heavy equipment tech but have no experience with vintage Mack stuff. I learned  today that the wheel cylinders and brakes have been replaced multiple time by previous techs. 

    I finally got a chance to crawl under it and I didn't even know it had a brake booster until I was looking at it. That would make total sense if the brake booster wasn't functioning properly. 

All 6 volt electrical will be pulled and 12 put in its place 

I'm not exactly sure what he is expecting either as far as performance. I do know this though, he wants to pull all plumbing, water pump, engine and trans and go back in with a fuel injected 350 with auto. I'm thinking we wants the look of vintage with it being more streetable. It is not going to get towed to locations but driven.

I'm not sure where to start so I figured this is the best place as any.

I work for a City Municipality in the fleet department. They have a 1940's Mack Firetruck that they are wanting to use in parades and events. My boss says that hi is not happy with the performance of the factory 4 wheel drum brakes and wants to upgrade to a more modern braking system. I have no experience with these trucks but I can tell that will not happen with the current wheels and axles. I am thinking  that a modern axle swap would be the best route. What are the opinions on that?

if I do an axle swap, I think I would need to find a drop I beam for the front so that the ride height doesn't change or can I do a spring under solid front axle like out of a modern 1 ton truck? I also thought that if I could find modern knuckles that fit the 40's drop axle I could go that route. 

Any info would be greatly appreciated or if you just want to spitball ideas that would be awesome.

Thanks,

David