Anyone know what this pulley is?

[Cryptothedog]

What is this pulley? It wobbles back and forth while running. It has a lot of play, I can wiggle it when stopped and seems to be making a lot of noise.

 

[B-train]

What's connected to it? Large coolant hoses or 1 smaller diameter hose? The location looks to be the vacuum pump, but it's hard to tell by the picture.

The vacuum pumps on these have a bulletin for replacement. Are you experiencing harder than normal brake pressure? Or very little assist at low speeds?

If the coolant hoses attach to it, then it's the water pump. I'll check mine when the wife gets home if nobody else chimes in before then.

 

[Cryptothedog]

What's connected to it? Large coolant hoses or 1 smaller diameter hose? The location looks to be the vacuum pump, but it's hard to tell by the picture.

The vacuum pumps on these have a bulletin for replacement. Are you experiencing harder than normal brake pressure? Or very little assist at low speeds?

If the coolant hoses attach to it, then it's the water pump. I'll check mine when the wife gets home if nobody else chimes in before then.

Large coolant hose is attached to it. Should I be able to wiggle that pulley side to side with my hands? It seems like it has a lot of play and I think it is making a lot of noise

 

[B-train]

That is your water pump. No side to side is good. Noise is bad also. You need a new water pump. I advise getting a GM thermostat while you are at it with the system drained.

 

[B-train]

You don't have much time left before it leaves you stranded either with a major coolant leak, or a pulley in the belly pan

 

[Cryptothedog]

Brakes seem fine to me. The truck runs fine. I did have to replace the thermostat about 2 months ago. Now it is just making a bad noise that sh

That is your water pump. No side to side is good. Noise is bad also. You need a new water pump. I advise getting a GM thermostat while you are at it with the system drained.

I actually replaced the thermostat about a month ago because it wouldn't heat up. Guess I'll do some research on how to change that. Thanks for the help

 

[B-train]

No problem. It's a fairly easy job. A few hose connections and some bolts and you are on your way. GM uses nice gaskets on these, so no scraping involved. You'll probably want 4 gallons of premix dexcool to replenish and burp the system. I'd recommend only GM OE parts fyi

 

[Doubeleive]

What is this pulley? It wobbles back and forth while running. It has a lot of play, I can wiggle it when stopped and seems to be making a lot of noise.

mine started making some noise around 36k I couldn't figure out exactly which pulley was making noise I thought it might be the vacuum pump as those are the most common to fail, but I kept looking and looking and it kind of didn't change much then one day I noticed a small drip on the ground and looked again and the water pump pulley was barely on and was wobbling like crazy I was a few miles form the dealer and somehow managed to limp it there. funny because I was under warranty and the service guy was like of well have to check it and I was like um come take a look lol there isn't much to check on this, they had it knocked out a couple hours later.

 

[Doubeleive]

No problem. It's a fairly easy job. A few hose connections and some bolts and you are on your way. GM uses nice gaskets on these, so no scraping involved. You'll probably want 4 gallons of premix dexcool to replenish and burp the system. I'd recommend only GM OE parts fyi

alternator and mounting bracket has to come off, the rest is a breeze

 

[Cryptothedog]

No problem. It's a fairly easy job. A few hose connections and some bolts and you are on your way. GM uses nice gaskets on these, so no scraping involved. You'll probably want 4 gallons of premix dexcool to replenish and burp the system. I'd recommend only GM OE parts fyi

Awesome! Thanks so much for your help!

 

[Cryptothedog]

Do you think it is ok to just change the pump by removing the pulley or should I do the whole assembly that involves removing the alternator bracket and thermostat and stuff?

 

[Tahoe14]

You could try a Google search and see if there is a Youtube showing how to remove it.

 

[Doubeleive]

Do you think it is ok to just change the pump by removing the pulley or should I do the whole assembly that involves removing the alternator bracket and thermostat and stuff?

it's all one piece, I don't think you can just change the pulley

 

[Doubeleive]

this is what the assembly looks like, the 2 bolts on the far left are under the alternator bracket, the tensioner just below and to the left of the pulley has to come off as well
as the sensors and connectors

 

[Cryptothedog]

it's all one piece, I don't think you can just change the pulley

Yep you Can! I just did it.

 

[Doubeleive]

ok, but now what? have you found that part of the pump sold separately?

xxedit, ok I see that is sold separate, however I would inspect the inner housing pretty good to make sure there is no pump wear or anything otherwise it may end up leaking, good luck, learned something new. when mine was replaced they did the whole assembly.

 

[Cryptothedog]

Yep acdelco part 251-821 or duralast makes one too. Put it on and it works like a dream. No more wobble