Had clutch replaced, along with engine. Now, on the 1-2 shift, when my wife drives, it's jerky. Does it to me sometimes too, but not always. The rpms bob, the car lurches.. makes me think the engine mounts are bad. (Although then it would do it always, right?) Is this normal?

Another reason I think the mounts may be bad, is in 4th and 5th there's a noise.. Like the engine is vibrating against something... feel like load may have something to do with it, as it's only happening in 4th and 5th. It doesn't do it in 1st, 2nd, and 3rd, not nor does it make this sound when the clutch is depressed. It also does not make this sound when the car is not running. (Sorry, I had to. 😂)

Also, how are those "low mileage" "good shape" 45k-60k mile engines from eBay? Are they typically without problems, or should I be expecting to replace it again in 6 months from a spun bearing?