Downshifting problems
 

Hi I have a 2012 Lexus IS350 AWD with 30K miles on it right now. When my car shifts from 4th to 3rd the rpm go lower than when it shifts at other gears causing a jerk and a clunk sound. To battle this problem, I can time the shift and use the paddle to down shift to 3rd and then it doesn't do it.

I do drive my car a bit harder than most I would think, I accelerate hard but when I stop i stop normally, I don't stop super fast. The car is still under powertrain warranty. I have resetted the ECU a few times, didn't really notice much difference.

In general the car doesn't shift that smoothly, it might be a mount for that. When I accelerate too, i feel a bit of jerkiness (like you feel the engine move, or at least that's what i think is happening).

any problems driving in auto? paddling shifting is terrible in the IS

I drive in auto. That is the problem. The only reason I use the paddle shifter is when i'm coming to a stop and I'm watching the rpm shift from 4th to 3rd, I use the paddle to shift it myself so it doesn't cause the jerk/clunk

The jerk is the engine braking and is normal. You can try "blipping" the throttle like on manual cars to get your RPMs higher before you downshift to make it smoother.

Quick clearance
 

I didn't mention that the problem appears to only happens from 4th to 3rd. Sometimes the car downshifts from 4th to 2nd causing a jerk. But the downshift clunk and jerk almost always happens from 4th to 3rd. My friend told me it could be a failing gear. But the car has only 30k miles on it, and is still under powertrain warranty. Any suggestions on that?