Re: PS Pump
The correct part# as per GM is 26045642...and it has the EVO electrical connector for the "magnasteer" feature...but good like finding it, because I spent more than a week looking for one for my '92 SSE */c last year, and according to my local dealers, their network of dealerships had only ONE new one on planet earth, and it cost $426! So I ordered one from gmpartsdirect, but within a day or so they informed me that the pump is not available. So I ordered a rebuilt pump from the dealership twice, yes twice, because both times the pump they received ended up being the wrong part when I went and looked at it!
I had the same problem with local AutoZone, Kragen, and Pep Boys stores. The pumps they said were the right one were not the right one. The pump# that turned out to be the right one was a rebuilt Cardone pump #20-42832; it comes with the reservoir, but not the EVO assembly. I removed the EVO assembly on my old one and installed it on the rebuilt one. My old OEM pump had #26021734 on its sticker, and mine didn't leak or squeal but made a rattling noise that was most noticeable at idle.
I recommend taking the pump off the car and bringing it in to compare with the replacement. Note that the reservoir and the EVO unit are removable, so the pump looks very different without those parts attached....and good luck removing your pump from the engine bay...disconnecting it is easy, but figuring out how to remove it from the engine bay is an entirely different matter! I spent hours trying to figure it out, and it seems it can only be removed from below, and even then, I had to rotate it several times and use some force to get it out. Putting it back in was a bit easier, but a bit of force is still required to move it past different areas near the wheel well. If you find an easy way to get the pump out of the engine bay, I'd like to learn how. The dealership mechanic said he removes a crossmember, but he didn't know what he was talking about...and he also said that a power steering pump doesn't make a rattling noise when it fails, but that'* what mine did, and he didn't believe me.
'99 Bonneville SLE, white, 112,000 miles
'02 Park Avenue Ultra, white diamond pearl, 88,000 miles