Kicking on road as i drive or accelerate up a hill

indications are that although you have the foot flat to the floor , the message is not getting to the ECM to open up the injectors
Have the fault codes read and check for problem accelerator position sensor

Depending on the slope of the hill, it could be kicking in and out of overdrive. This is normal to a point. I would take it out of OD if there were a lot of hills to climb. Better for the transmsission.

the kick down cable is a mechanical connection that down shifts a transmission when the accelerator is wide open and the road speed is too low
as when going up a steep hill you have the throttle wide open and the vehicle needs to change down gears or the engine will stall
so no cable now down shift when required
run the fault codes as I would not think that the cable is the problem

if your truck is a has auto sensors they are adjusting to road conditions , could be a loose sensor if it is a problem , look on youtube to find out more ,

Look into exhaust, clogged cat conv. could cause that. Best way to test is a vaccum test on the intake. When exhaust is restricted the vaccum should go to 0 at the intake manifold while accelerating.

is the engine reving high on a hill and your going nowhere ??? if so sounds like clutch to me

there is a problem in your gear shifter located insde your transmission. have a transmission expert check your transmission, since this is not a DIY job.

As to any cars, when it snow, and going up hill there will be promblems, best way for the tl is turn on the vsa, put it in a low gear, like d1 d2.... and slowly press on the accelerator. Best solution is to stay away from hills until road has been trreat. Remember your Tl is only 2wd drive front wheel. It won't be able to handle like a 4wd or awd.

I would start with checking u joints first they can make more noise if under more load.

have u replaced the fuel filter to see if this helps? that is what I would do 1st.