fan clutch?

Hi,
My envoy xl is making noise like the fan is always on. The noise gets louder the faster you go. No check engine lights. Could this be a problem with the fan clutch?

Hi,
My envoy xl is making noise like the fan is always on. The noise gets louder the faster you go. No check engine lights. Could this be a problem with the fan clutch?

Sounds like it although in my experience when it completely goes i trips a code. Does it go away after a while? Both time's my fan clutch went out the noise it made sounded like a big rig accelerating, And my truck lacked power, if yours does this it might just be the fan clutch

Sounds like your fan clutch is toast.

Check out this thread.

http://forums.trailvoy.com/showthread.php?t=19604

:iagree:

sorry dude, if your vehicle sounds like a bus all the time, your fc is shot. The clutch is stuck on full power meaning it is now directly tied to the engine output. Reduces power and gives you the distinct impression that you now drive a city bus.



The dealer will want about 500-600 to do this job.

If you do the replacement yourself (plenty of info on this site about it) then check out this: http://forums.trailvoy.com/showthread.php?t=34812

Also check out e-fans if you're not an avid off-roader.

Fan clutch for sure. Just replaced mine. I learned that spend a little money extra and get a an OEM or similar quality replacement. You can get one at NAPA for a little over $200, e bay usually has them as well for around $150-$175. I went cheap and had to do the job twice. You can have the one I got from autopartswarehouse for free...I just would'nt put it on. Great door stop now.:mad:

Thanks,
I think I am going to fix it next week when it warms up a little. Do you think that if I wait it will do other damage? :undecided

I just did mine yesterday. It only took an hour. It is much easier than it looks. No need for a special tool. We used a air punch to break loose the fan clutch from the water pump. Then used a pry bar wedged in the water pump bolts to tighen back up. Good Luck

Thanks,
I think I am going to fix it next week when it warms up a little. Do you think that if I wait it will do other damage? :undecided

I don't think it'll break anything. but I wouldnt go barreling down the highway at 120mph, (or 60 for that matter).

Remember, the clutch is stuck on its lowest ratio. This means that the harder you push your engine the faster that fan will spin regardless. You can still drive it, just be nice to it.

Hi,
My envoy xl is making noise like the fan is always on. The noise gets louder the faster you go. No check engine lights. Could this be a problem with the fan clutch?

Your Envoy is a 2002, so I think you have been lucky to have the Fan Clutch last this long! Yes, I am sure it is the clutch assembly. Mine went a year ago (i have a 2002 TB). I also got the Check Engine light when it did, because the electric control burnt up and tripped it!

Just something to think about....if it has pretty high mileage (over 80K or so) consider changing the water pump at the same time. It isn't tough to do, especially since you have to take off alot of the same stuff to do the FC as you do to do the pump. If it has as much mileage as mine did, the coolant lines going to the bottom of the pump assembly will probably be pretty well rotted, so you might have to change those also (mine were).

Good luck!:)

Your Envoy is a 2002, so I think you have been lucky to have the Fan Clutch last this long!

:iagree:

consider changing the water pump at the same time.

:iagree:

Good luck!:)

:iagree::iagree::iagree::thumbsup:

Does the check engine light have to come on for it to be the fan clutch?
Thank to all that have replied.:thx

Does the check engine light have to come on for it to be the fan clutch?
Thank to all that have replied.:thx

Long before my Check Engine light came on, my FC gave indications that it was on the way out.

In the first few minutes of operation, the fan clutch would be somewhat loud. Then, after putting the TB in gear and starting out, the fan clutch would absoultely ROAR! It would sound like one of the jets I take care of during take-off! After the first few minutes of that happening, it would suddenly stop and act normally.

Then one day, I started it up and noticed that the clutch seemed quiet...but I got a burning wire insulation smell coming from the engine compartment. That's when I noticed that the Check Engine light had illuminated.

So in answer to your question, the Fan Clutch can malfunction long before the light turns on.....but you can bet that given enough time....It WILL turn on!!::ugh:

I guess, after reading through all the fan clutch issues listed on this site, I have to accept that mine is shot too. I've got the whole "city bus" sound, check engine light and even the tapping sound intermittently. My questions are:
1) Are they any brands of this part to stay away from? It sounds like some people have had problems with certain brands. Is there one particular one that we can be confident will work? Went to the GMpartsdirect.com, b/c we'd prefer an original GM part, but it's a special order (non-returnable) part which concerns me when spending ~$300. Anybody know of any other wholesale actual GM part distributors?
2) The programming update that the dealer thinks is worth $100, is it necessary to make the aftermarket fan clutch work? Will the dealer even do the update on a part not replaced by them whether it's a GM replacement part or other?
3) My husband is a motorcycle mechanic. Would this be an easy enough repair for him to do? Sounds like the fan shroud is the biggest headache. Are the specialized tools really a necessity?

Any answers you guys could provide would be a huge help. This site is great & sooo glad I found it. You guys have already saved us a pretty penny on diagnostic stuff! Thanks!

I guess, after reading through all the fan clutch issues listed on this site, I have to accept that mine is shot too. I've got the whole "city bus" sound, check engine light and even the tapping sound intermittently. My questions are:
1) Are they any brands of this part to stay away from? It sounds like some people have had problems with certain brands. Is there one particular one that we can be confident will work? Went to the GMpartsdirect.com, b/c we'd prefer an original GM part, but it's a special order (non-returnable) part which concerns me when spending ~$300. Anybody know of any other wholesale actual GM part distributors?
2) The programming update that the dealer thinks is worth $100, is it necessary to make the aftermarket fan clutch work? Will the dealer even do the update on a part not replaced by them whether it's a GM replacement part or other?
3) My husband is a motorcycle mechanic. Would this be an easy enough repair for him to do? Sounds like the fan shroud is the biggest headache. Are the specialized tools really a necessity?

Any answers you guys could provide would be a huge help. This site is great & sooo glad I found it. You guys have already saved us a pretty penny on diagnostic stuff! Thanks!

I think your hubby could probably handle it. Try Rockauto.com for parts. I have used them before and they are a bit cheaper.

That being said, I always try to go with GM parts on repairs like these (although I am sure that the Fan Clutch is probably made by ACdelco for GM). As you said, GMPartsdirect is good place.

I don't think you don't need the tools to do the job. But as always, it is easier if you have them. I actually had mine fail in cold weather and I didn't have time to do the repair myself, so the dealer did it. They WERE going to charge me some outlandsih price like $500+ dollars for the FC, plus labor for the change....but I chewed their ear off about how GMPartsdirect was selling the part for 1/2 that! And since I was bringing them the repair, they should charge me THAT price. They did!

But I have read here that it isn't a bad change....just a lot of wiggling things into place.

Good luck :)

But I have read here that it isn't a bad change....just a lot of wiggling things into place.

Good luck :)

Here are a few paragraphs from two posts from people who have done the job. Hope it helps you!




This thread is for all those who believe that their fan clutch is going bad. If your fan sounds like a jet engine on take-off while you are increasing speed and your check-engine light is on, your fan clutch may have to be changed.

In order to change the fan clutch, what you first need to do is purchase a new fan clutch; it appears that only the dealer is selling them. I purchased mine for approximately $265.00. You also need two wrenches: one large enough to go over the four bolts of the water pump, the other (could be a large adjustable) to go over the nut that screws over the shaft. I got mine from Autozone, free of charge. They only need a deposit, which they later reimburse.

To do the job takes about one hour or less. Using a half-inch wrench, remove the four bolts holding the fan blades to the fan clutch. With the larger wrench, hold the four bolts from the water pump while unscrewing the large nut from the fan clutch with the other wrench; it is a regular thread, so it unscrews counterclockwise while viewed from the front. It is a little tricky to take out the fan clutch between the fan shroud and the radiator (I removed the two bolts from the fan shround in order to give me more play). Put the new clutch in place and screw the nut into the shaft clockwise. When everything is finished, you'll take a ride and be very pleased that the awful noise has dissapeared. It takes 10-15 times of starting and stopping the car for the check-engine light to go out.

Hope I was helpful and saved you a few bucks. Good luck.

Gizmo

================================================== ========

Just wanted to write this up for the novice mechanic like myself and anyone else who might find it useful. My first attempt to replace the fan clutch on my ’02 Trailblazer failed because I wasn’t patient. These steps and observations are what worked for me and in no way represent the best way to accomplish this job. The original post by Gizmo97 has great information but I wanted to add a few more details; it was that post that convinced me I could do this job.
First, I found that the tool for rent from O’Reilly Auto Parts worked well for me. I was able to hold the water pump by the bolt heads and the smaller of the two wrenches that came with it was an exact fit.
I loosened the fan clutch nut from the water pump first using the tool but did not completely unscrew it. The nut has normal threads so to loosen it, turn the nut counter-clockwise. Next, I removed the four bolts holding the fan to the fan clutch and pushed the fan against the engine block. This allowed me clearance to put some cardboard between the clutch and the radiator and avoid bending radiator fins. I also removed the cable harness from the top right of the fan shroud. Removing the top left and right bolts holding the shroud in place allowed me to pull it up about a half inch; every little bit counts. I completely unthreaded the clutch at this time but because of the tight space I was not able to gracefully pull the clutch off the water pump; it fell to the bottom. At this point the clutch is sitting below the water pump but still in close quarters with the fan. The idea now is to pull the fan out first. To accomplish this hold the clutch flat against the radiator and maneuver the fan; the hardest part is getting the nut past the rim of the fan. The top of the shroud will flex a little as do each of the blades on the fan and this allows the fan to be removed. You may have to rotate the fan to get it past the water pump bolts but it will come out. Also, it is a tight fit around the top left side of the fan; I want to call this part the valve cover but it isn’t. I will call it the oil fill area. I had to bend the fan blades to get past this point. Once the fan is out, the clutch can come out very easily. The installation of the clutch is the exact opposite of removal. Don’t forget to pull out the cardboard!
Hope this makes the job easier for someone. Saved a boatload of money by trying it myself so it was worth the trouble. Lowest quote I got from a dealer was $700 with $331 going for the clutch. Spent $194 for the updated clutch, rental tool was free, and I still have to take it to get the PCM updated for $40 but still significantly cheaper. Good Luck!

I installed my new Behr fan clutch this weekend and it went well. I also put on a new serpentine belt while I was there. The tip to put a piece of cardboard in front of the rad. is a good one. I did not rent a tool, I just took out a bolt, drillled a hole in a piece of a steel bar clamp, put the bolt back in thru the bar clamp and used it for leverage. :thumbsup: