I just did all four u-joints in my axle shafts this spring. I have heard Spicer are supposedly the best but, when doing my research the Spicer part no. 5-4X required for our cars appears to be NLA since Feb 2008. Not sure if that is 100% true but, I did a very extensive search
I ended up going with my local NAPA 3301. On the box it will say "Premium part no. PUJ 344" with good circlips and long grease fitting. The box states Federal Mogul and made in USA. It is the same as Precision brand by Federal Mogul. These are very substantial looking u-joints and it took them a day to get them since they didn't normally stock (4) of 'em. Cost was $27 each. Do not get NAPA's "Proformer NPJ344". These are made by GMB in Japan.
The Premium u-joints came with very long grease fittings which interfered with the axle shaft yokes once everything was installed. So, after I completely greased them up, I removed the grease fittings and replaced them with a Ā¼ā 28 threaded Allen plug (1/4" long) from the local hardware store. I am very satisfied.
Bob