I have bought an old Ford Fire truck 1940 1 1/2 ton 95hk. comes upp in a speed
max 25-30 mph normal?
Engine feels run well .but the truck feels heavy end powerless.
Where to start troubleshooting, improvements ?

 

It would seem that You'd want to go faster than 35 MPH to get to a fire, unless the fire was next door to the fire station. Does the truck have a two speed rear end?

 

i dont know
how to check that ?

 

Hi Lars, If you have a two speed diff you will see the shift arrangement mounted on the left side of the diff head, shift lever going into the diff head, vacuum chamber to operate it. (late model Eaton diffs have an electric motor)
My truck has a single speed diff .
Good luck, Steve.