My car won't shift from 3rd into 4th when I'm over about 5k in 3rd. I don't know much about transmissions so I thought I'd ask.

Also, there is a destinct pulsation in the shifter when at part throttle at high revs, i.e. entering a highway in 3rd at high revs just so I can be ready to accelerate hard if needed.

Lastly, my car HATES it when I take my foot off the gas in first. I'm talking about when the revs are high enough that it won't stall. If I go to 4k in first, and than take my foot off the gas, it will jerk everywhere and the shifter feels like it's trying to pop itself out of gear.

I listed all my problems in case they're connected.

Any idea what's wrong? I most concerned about issue 1.

Thanks