If by juddering you mean at the steering wheel, then I would check all your wheel bearings and alignment.
If my last two weeks’ experiences have a “moral of the story” it is, don’t trust ANYTHING a PO may have done and check / then double check all your drive train, suspension and steering nuts / bolts for completeness, torque and correctness (I.e. properly rated bolts where load bearing).
The UJ thing mentioned above makes sense.
Now this may sound silly but also check your wheels are squarely mounted on the hubs with no rust or paint blobs. Then check all wheel nuts are tight. My Brother in law who is a wizard in the kitchen but utterly useless with mechanical things equal measure, once drove back to London from Devon and told me he had a strange vibration from the rear that went away if he went over 80mph. I went cold knowing exactly what had happened and shot over with a torque wrench - he had put the rear wheel on himself and not torqued the bolts enough - so by the time he got to London 4 were totally loose and one was only finger tight [emoji33][emoji33][emoji33]