Vacuum Pump Squeak

[David_Jennings]

I have a squeak in my vacuum pump. No codes. I sprayed it wih W.D.40 and the squeak disappeared. I wonder, (1), is there a way to lubricate the pump? (2), will I get a check engine light if and when it goes out? (3), is this pump covered under the engine warranty (I still have 35,000 of coverage and 4 months under the 100k warranty. There is no mention of the pump in the warranty handbook. Thanks.

[GARY PAGE]

It does have oil in it or should have. In order to get the oil in it you have to remove the pump turn it upside down and remove the diagraph from the pump housing. You will see the small cavity where the cam lobe is at, that

[whatnot]

Originally posted by David Jennings:
(2), will I get a check engine light if and when it goes out?I have 2 trucks with them and my brother has 2. Out of the 4 trucks, we have had them all go out.
2 of them just quit making vacuum (will cause a code 78, I don't know the number on '96+) 1 of them made a loud noise that sounded like a bad engine knock and the other one froze up and busted the belt.

[ANXIOUS-SUBMAN]

My vacuum pump has been squeaking for a couple years. Today I replaced my sert belt so I took the opportunity to pull the pump to investigate. I separated the pod from the cam/drive section. Operating the drive section produced no noise. Manually operating the plugger in the pod produced the squeaking noise. I sprayed silicone into the inlet tube on the pod. Now the squeak is gone. I spilled some of the oil from the drive section during disassembly so I topped it off before reassembly being careful not to overfill. While test driving the truck afterwards I hadn't realized how accustomed I had become to hearing that squeak. Much nicer now.

[JohnC]

If memory serves, that's gear oil in the pump, not engine oil. Or maybe that's what they recommend on replacement...

[ANXIOUS-SUBMAN]

I think the squeak is just starting to come back. I figured the shot of silicone wasn't a permanent fix but at least I know where the squeak is coming from now and I know I won't have to replace the whole pump, just the pod section. Does anyone happen to have GM part #s handy for the pod section or the whole pump?
Thanks,