Greetings! Glad to have found ya! I'm the original owner of a 2003 Silverado 1500 LS, 2WD, 4.8L. This is by far the most reliable vehicle I have ever owned (and I've had a ton of 'em). She's a cream puff and quite frankly, I can't bring myself to replace her. I just don't see the point in spending $35K on a new truck.

Anyhoo - what AC Delco calls the "Power Brake Booster Vacuum Pump" has failed. This is NOT the traditional brake booster found in between the master cylinder and the fire wall. This devices is located on the side of that booster. The A/C Delco part number is 89058946 and it's apparently discontinued. I've looked around to find one (not too crazy about going used for a brake part) and I'm having trouble.

I did find one listed at a place called "OEM Cats", but they look kind of shady. Has anyone ever bought anything from these people?

Also, if anybody has any ideas on where I might find a left over NOS part, I'd appreciate it.

Thanks for any assistance provided.

 

Is this it?

https://www.rockauto.com/en/moreinfo...412075&jsn=485

 

No - that is not it. That is the old "hydro-boost" style of brake booster. The part I'm looking for is a vacuum pump motor that serves as a supplemental brake booster for the regular diaphragm style booster that is located between the master cylinder and the fire wall. This part is mounted on the side of the regular vacuum booster.

It's hard to imagine that Chevrolet just stopped making this part.

 

Its not just Chevrolet. Lots of companies are having to cut costs anyway they can these days. Might check the wreakers. If they dont have it, they have a network that can find one.