Problem with brake system of dodge t110

[serge]

Hello GORDON

I thank you for your answer. I own the technical manual and it is written that the booster should be oiled with the engine oil. I had soon examined the inner of the booster and I had saw that it's surface was in a good state.
Following indication of the technical manual, the return of brake pedal is the result of 3 actions.
1/ Sprng inside Booster
2/ Vacuum in front of the piston of the booster
3/ Pedal pull back spring

Nevertheless the last indication seems to be a mystery because there is no attach for a spring in the rod associated to the master cylinder.
I have to find the kind of oil you have told in you previous post

Regards Serge