Brake chambers..

Ya it does take an extra deep socket.

 

Just an F.Y.I. , drive tandems with only one axle of combo (service/emergency) brake chambers can only be rated to 36,000lb gross axle weight rating instead of 40,000 GAWR like the axles are rated at. From KW data book.

 

A ratchet wrench can also be used.

 

Aint Broke Dont Fix

 

Of course. But a socket and impact is much much faster.

 

But not proper

 

I had a 1993 379 with 40k rears it only had 2 spring brakes. Other axle was just the can for application. Now my 01 has 4 spring brakes on a 34k rears. Mayby this is something more recent. Trying to figure out by having 4 or 2 has anything to do with how many lbs the axles can carry. Oh well.

 

Braking power. If you need to pop the park button in an emergency situation only one axle will provide braking. Same as for parking ability on a hill. Probably not capable of holding 40k lbs adequately on a grade.

 

Pretty common for the old iron to only have maxis on 1 axle. I have a 90 and a 84 and they both only have them on the front drive axle. They're both rated at 40k

 

I never been in a situation to even think of pulling the buttons on the dash. 2 on tractor and 4 on the trailer have been plenty to hold 100-120 on any hill I've been on. I only have 2 on tractor and never pull the red button but don't haul to much over 80 gross any more either.

I think it has more to do with who specs the truck and trying to save a dime here and there.