I'm looking for a power steering pump on Rockauto.com and they have several different ones listed. My truck is an 07 2500 5.9. They are listed as either: "Except ZF Pump; with Snap-Ring Retained Backplate" or "with ZF Pump; with Bolt-On Backplate" Does anyone know the difference between a ZF pump and a non-ZF pump?

 

I'm gonna say bolt on back plate. Due to the 3 bolts that need to be taken out to remove the pump, leving the mounting plate on the engine. Have the same truck and have done a new PS pump twice. 1 from Napa, lost the recepit, 1 from Oreillys.
The last one I bought complete with reservior, think it was a waste of an extra $30. WOuld get a new o ring though for the reservior connection.

If you haven't done it before, the pulley is kind of a pain to get off. Tried just getting a new pulley locally but the part #'s are all wrong. All teh autoparts stores list/stock them but they are the wrong size, too narrow.

It's a chore to pull the old pulley. I ended up using a small 3 jaw puller pulling on the little front flange of the pulley. Had to grind teh puller jaws down do it fit perfectly around the small raduis and run the puller against a dummy bolt in the shaft countersunk so that it wouldn't walk off the shaft. Wired the puller tight around the jaws to keep it form slipping off.
Somehow I had the right metric thread bolt to thread into the shaft in my bolts drawers!

All in all the ps/hydro boost pump is more of a biatch to r&r than it should be.