D5B Steering Action

I've been running a older D5B with powershift transmission and have a question regarding the expected steering response.
If I'm not carrying a load on the blade, the steering levers seem to do nothing. The dozer won't start to change direction
until the lever is so far back that I'm applying the brake. Happens in all forward / backward gears. If I'm moving up a
steeper hill or have the blade on the ground the steering clutches work as they should and the dozer turns in proportion to
how...

D5B Steering Action

D5B Steering Action