Next up: Double cardan. Well, the story behind that is, after I got the lift from Jason @ Cruisin Off Road, I had a driveline vibration coming from the front driveshaft. I was warned that with that size a lift it may happen and I may need a double cardan shaft to eliminate the vibration.
So I went into a local wrecker, asking for a rear shaft from a 1995 to 2004 Tacoma 4x4 (1st gen) as Jason said the flange would bolt right up, and the other end could be welded into my existing front shaft.
They sold me one, for a reasonable $50. I brought it home, took my front DS out, with the intent on going to the machine shop the next day and getting them to weld them together. When I was looking at the two shafts on the bench, I thought... why does the flange on the double cardan shaft look bigger than my stock 80 series flange??? Figured it was an optical illusion due to the larger joint itself.
Well, luckily I stuck the two together, and ran a couple bolts threw them. Turns out the double cardan flange WAS bigger. By about 2mm. Nearly the same size, but way too different to work.
Called up the wrecker, politely asked if they had indeed given me what I had specifically asked for... followed by silence on the phone, and "Oh... no, we gave you a newer 4-runner shaft... I thought they were the same".
Glad I hadn't yet paid the machine shop to weld it to my shaft.
I went back into the wrecker and he swapped me for an ACTUAL tacoma shaft, which bolted up perfectly.
Brought the shafts into the local machine shop, that afternoon went and picked them up.
Bolted it to the truck, everything looked great. Put my skid plate back up, and took it for a test drive expecting perfection.
It was worse than before. WAY worse. It was so bad, my toolbox in the back was bouncing around with the vibe.
I called the shop, they assured me it was straight and true, within 0.002... so I bought myself a dial gauge and measured. Laying on my back under the truck and running the front wheel (lifted in the air) like a hamster wheel, I measured 0.002 on one side of the weld and 0.0025 on the other. Ok... so it's straight. Well WTF?
Out came the DS again... then I noticed that the front ujoint (non double cardan end) was very, very stiff in one direction. Weird? It wasn't like that before the shop had it.
I replaced the front ujoint, and it was much better... though still had significant vibration. It was still stiff, too, in the one direction. John suggested perhaps the ears of the yoke were a bit squished. Now, not to BLAME the shop, but... it wasn't like that before.
John showed me how to stretch out the ears of the joint using 1/2 inch grade 8 fine threaded rod and grade 8 washers and nuts. I managed to get it to be silky smooth in both directions, bolted the DS back up (again... sigh) and... perfect! Drives nice and silky smooth now
) I wanted to actually fix the leaky pump.
No more wining. No more leaking. 
Not sure what I did wrong / or what's wrong. At the point buying a brand new pump isn't out of the question!
