Anyone running pro comp es3000's. Four Wheel Parts has a special going on right now for four shocks a es2000 steering stabilizer and four boots for $135.00
I got the 9000's. Don't really know waht the difference is. I do know I like them and even though they did not come with all the hardware I had no trouble using the oem stuff. Whatever you get will be a vast improvement.
If you want Pro Comps, I'd to to a 4 Wheel Parts store if there is one near you to get them installed, they own Pro Comp so let them deal with the missing parts.
My ES9000's had no crosspins in the front shocks and getting the ones out of the OE shocks, while possible, wasn't easy being that my shop and tools are more for carpentry than mechanics.
I got one on finally, next day tried the other front which didn't try to expand itself like a gas shock should (and like the other front shock did). While they didn't come with crosspins, there were way more nuts and bolts than was necessary. I gave up, drove to Sears on three shocks, bought SensaTracs installed for $198, took the wife for drinks and dinner at the mall while Sears was working on it, and sent the Pro Comps back for a refund. I never got as far as trying to install the rears because I'd had it and was pissed off. The beer made me feel better though.
Shocks for a 2001 Explorer will be the same part numbers. I did a Search here to get the Pro Comp numbers.