WOW...long time getting back to this, holy smokes! Well, when I left off I had been working on the pump sizing. I did use the big Commercial pump I had like Bjorn's and it worked out GREAT! All functions of rams and oil motors have very comfortable speed to them. The valve block itself is preset to 3,000psi (iirc)...I've never checked actual pressure but the thing works so well I'm not concerned with where the pressure is. The pump is driven via transfercase PTO. I run straight thru in 4th gear and have a 10% overdrive in the sprocket set that drives down the the shaft and pillow block then back to pump.
The load holding valves in the 'boom up' rams are really impressive with their holding ability as when the crane is boomed down, it will bog the engine down (225hp 1160 CAT) as it powers the oil past the holding valves. The same on the outrigger rams...but not quite as dramatic engine speed reduction.
As Mangus mentioned earlier...the dropside was cut and shortened to 8'- 1" inside length so 8' stuff would fit with the gate closed.
The biggest delay and ENORMOUS pain in the rump was the ultra low grade aluminum castings that hold the operating handles onto the valves. After running the crane a couple of times and have them piss out fluid in high pressure form some investigating realized that they had hairline cracks in them like the whole rack of valves had been dropped or impacted somehow at one point. I took them to a welder specializing in aluminum, gave specific instruction...after 6 weeks of not doing them he forgot my instructions and destroyed all 4 castings. These castings run $400-$500 through Grove...x4 makes you want to slam your hand in a door. Then, they got sent to a machine shop outside Salt Lake where they were to be blue printed and remade out of new billet aluminum. Well...about 2 years and several call to just, '...no hard feelings, just PLEASE send them back,' finally got them back where a member here and a friend finally was able to get the done! Whew.
It's been up and running for maybe a month or two now and I'm using the daylights out it! Heaviest lift so far was about 4,500 lbs (a Silver 92 w/13 speed RR still on 18' of chassis with the front truck axle and tires still on it. That's a BIG lift and I won't go heavier. Had to lift it to get the front axle out. First lift after getting all the new billet pieces back on was loading a 400hp 8V71 Detroit on a trailer for a guy. So nice...
The pics just show it lifting the base of a military engine shipping conainer that has a bunch of steel chunks in it. Had to move that out of the barn so I could fit the truck in to change the transmission. Front bearing let go, see that pic.
Weights: Truck as seen in picture is 18,010 lbs. Scaled at 8,000 lbs front and 10,010 lbs rear. Also note A3 wheels and Conti' tires to up the front tire load rating as the stock NDT's were right at the top of their singled capacity.