Play and banging in steering (possible rack/u-joint issue)

[FourPointEight-is]

Hi,

I've got a banging/knocking sound in the steering rack. It is difficult to tell where exactly it is coming from. Jacking up the wheels and turning it freely in the air makes no noise - it only does it when the wheels are on the ground (i.e. the rack is under load).

I am 90% sure it all started when the subframe was dropped to replace the alternator bracket oil control gasket.

Do the racks in these cars go bad frequently?

I know there are two joints on the way to the rack from the steering, I suppose one of these going bad could cause the issue?

I can get a 2nd hand rack rather cheaply but I'd rather try to work out what's wrong rather than just throw parts at it.

Getting under the car to feel anything nothing feels abnormal to me.

I've done a ton of reading and it looks like the u-joint at the top can go bad causing these symptoms? Car is a 2005 4.8is with 130k miles on it so not exactly new.

Parts are at least a week away for me and I need the car back on the road ASAP - can anyone share tips and insights into what this could potentially be?

Thanks.