Duralast/Idler Pulley & Tensioner Pulley
- Thread starter joepro17
- Start date
They're cheap, like $20. Even if you choose wrong, it's not the end of the world. They give PLENTY of noisy warning as they deteriorate.
I've seen dozens of threads over the years from folks who spend 6 hours researching to find the best possible $20 part, then stamp their feet in frustration that we don't offer an illustrated step-by-step How-To guide or a Youtube video. 
Nowadays we can point most of them to MAY03LT's videos and they shut up and go away.
Nowadays we can point most of them to MAY03LT's videos and they shut up and go away.
Kind of reminds me of an "ad" for a Minecraft server I'd seen. They're like "Build stuff! Communicate with people!" etc etc, listing stuff that's literally a core component of the base game. May as well say "login! logout! play game!"The_Roadie said:I've seen dozens of threads over the years from folks who spend 6 hours researching to find the best possible $20 part, then stamp their feet in frustration that we don't offer an illustrated step-by-step How-To guide or a Youtube video.
Nowadays we can point most of them to MAY03LT's videos and they shut up and go away.
Now we need videos like "this is how you turn your vehicle ignition to ACC." "This is how you use the front windows in manual down rather than auto down mode." "This is the difference between left and right turn signals, and I'll provide an OTR example of what happens when you select the wrong direction."
just some additional info in case anyone is interested that i forgot to mention. when i purchased the pulleys at AZ i saw the screen when the guy pulled up the part numbers and they come up as Dayco pulleys. so turns out Duralast pulleys are Dayco pulleys just branded different.
ok, so i replaced both the tensioner pulley and the idler pulley today because i was getting that chirping sound coming from under the hood. wasn't able to tell exactly which part was making the sound. others seemed to have some success replacing either one of these to solve the noise (and parts were pretty inexpensive). unfortunately the sound still persists. i took a look at the belt and it seemed ok. hardly any cracks. i do notice the fan and power steering have some wobble to them. i don't know if thats normal or not. i'm a bit of a noob. can any one suggest another approach? additional note, if i hit the ribbed side of the belt with a squirt of water or wd40 the sound temporarily goes away.
thanks
thanks
Do the water trick where you take a spray bottle and spray tap water onto the back side (flat) of the belt, if the noise goes away then you have a tension issue. If the noise doesn't then spray the ribbed side of the belt, if the noise goes away then you have a pulley that is misaligned. I know you did the water side but just wanted to tell you what it means when you do it so you know 
you NEVER should use wd-40 or any lubricant on the belt. That is like putting tire gloss on the driving part of your tire and expecting it to have a good grip on the road. Water is the ONLY thing you should spray on the belt to isolate problems.
Since you mentioned spraying the ribbed part, spray just the flat and see if that affects it at all. Having a misaligned pulley isn't very common but can still happen and they are harder to fix sometimes than a tension issue. When you run the engine that wobble you are seeing on the PS pump and water pump should be almost non existent. My water pump has very little play, about 1/16" so its normal. My idler pulley has the same amount of play too. The water pump has 0 play on mine. What you can do that I do once in awhile regardless if there are any noises under the hood or not is to take some brake cleaner and paper towels and remove the belt and then clean every single pulley with the brake cleaner. DO NOT spray the brake cleaner on the pulleys as if you get some into the areas where the bearings and covers go it can break down the rubber covers and the grease in the ball bearings. Just spray the brake cleaner on the paper towel and wipe down the pulleys with it.
Can you see any glazing on your belts back side? Can you read the manufacturing information stamped onto the back of the belt or is it really worn out? If you look at the edge of your belt is it straight or somewhat cupped? When you experience the squeal noise has your truck been sitting awhile, has it rained since the last time it was running, are you putting the engine under load (like turning your steering wheel or loading down the alternator with a lot of electrical load)?
edit: any cracking on the belt is an immediate reason to replace the belt IMO. Don't take that chance of it snapping from age and fatigue while you are driving on the thruway or anything like that.
you NEVER should use wd-40 or any lubricant on the belt. That is like putting tire gloss on the driving part of your tire and expecting it to have a good grip on the road. Water is the ONLY thing you should spray on the belt to isolate problems. Since you mentioned spraying the ribbed part, spray just the flat and see if that affects it at all. Having a misaligned pulley isn't very common but can still happen and they are harder to fix sometimes than a tension issue. When you run the engine that wobble you are seeing on the PS pump and water pump should be almost non existent. My water pump has very little play, about 1/16" so its normal. My idler pulley has the same amount of play too. The water pump has 0 play on mine. What you can do that I do once in awhile regardless if there are any noises under the hood or not is to take some brake cleaner and paper towels and remove the belt and then clean every single pulley with the brake cleaner. DO NOT spray the brake cleaner on the pulleys as if you get some into the areas where the bearings and covers go it can break down the rubber covers and the grease in the ball bearings. Just spray the brake cleaner on the paper towel and wipe down the pulleys with it.
Can you see any glazing on your belts back side? Can you read the manufacturing information stamped onto the back of the belt or is it really worn out? If you look at the edge of your belt is it straight or somewhat cupped? When you experience the squeal noise has your truck been sitting awhile, has it rained since the last time it was running, are you putting the engine under load (like turning your steering wheel or loading down the alternator with a lot of electrical load)?
edit: any cracking on the belt is an immediate reason to replace the belt IMO. Don't take that chance of it snapping from age and fatigue while you are driving on the thruway or anything like that.
thanks for the info about not using wd40. i'll have to check later about the glazing and the manufacturing info. from what i recall, i don't think i saw any manufacturing info on the belt. when buying a new belt how can be i sure of the correct length? also does rib count matter?
idler pulley has no play. the tensioner pulley seems to bounce a little what looks to be as a result of the play in the ps and fan.
i'll try running the truck with the belt off to see if i am still hearing the noise.
idler pulley has no play. the tensioner pulley seems to bounce a little what looks to be as a result of the play in the ps and fan.
i'll try running the truck with the belt off to see if i am still hearing the noise.
There should be some play in the tensioner but not a large wobble like play. It should be slow movement in the tensioner. If it bounces around then your tensioner may be shot or another component like your fan or PS has play. Quick question, when you see the play in your fan do you see the same kind of play if you watch just the pulley for the water pump when the engine is running? My fan isn't balanced perfectly straight so it is warped a little but nothing to affect anything on the water pump or anything like that.
For the length just go to your nearest store and ask for a belt for a 2007 GMC Envoy, they have 2 options with a difference in the alternator size, I picked the smallest belt for my truck which iirc was for a 150a alternator but I have an aftermarket alternator that is 270a and has a smaller pulley than the OEM alt so the smaller belt is smarter for me to maximize the lifespan of the belt and travel of the tensioner when it starts to get longer as it ages. I am NOT a fan of dayco belts, I went through 3 on my truck before I said screw this with the belt squeal and bouncing I had from using the belt and went to carquest and bought a gates micro-v belt K060915. That belt has been in for 2 years now with 0 squeals, the only time it makes any noise is if I leave the truck sit overnight and its damp and the engine bay gets moisture in it and the belt gets a little moisture on it. When I start it up like that it squeals from the moisture for a minute or 2 until it drys out and then is totally quiet. No slipping under heavy acceleration and no bounce marks on the back side of the belt from it not gripping properly. My daycos had a life span of about 4 months before it would start to slip. You're certainly welcome to try them for yourself as they are cheap but I am sharing with you and everyone else here my bad luck with that crap. Dayco rubber just is total trash to me as I have had these same problems on 2 different vehicles both in the belt quality and radiator hose quality.
Rib count does matter but that really only comes into play with belt length, long ones like on semi's have more ribs and small engines like honda sometimes have less ribs. Our truck has a 6 rib belt with a 90" outer diameter (for the XL/XUV platform) and a 92" outer diameter for the standard length like you have.
For the length just go to your nearest store and ask for a belt for a 2007 GMC Envoy, they have 2 options with a difference in the alternator size, I picked the smallest belt for my truck which iirc was for a 150a alternator but I have an aftermarket alternator that is 270a and has a smaller pulley than the OEM alt so the smaller belt is smarter for me to maximize the lifespan of the belt and travel of the tensioner when it starts to get longer as it ages. I am NOT a fan of dayco belts, I went through 3 on my truck before I said screw this with the belt squeal and bouncing I had from using the belt and went to carquest and bought a gates micro-v belt K060915. That belt has been in for 2 years now with 0 squeals, the only time it makes any noise is if I leave the truck sit overnight and its damp and the engine bay gets moisture in it and the belt gets a little moisture on it. When I start it up like that it squeals from the moisture for a minute or 2 until it drys out and then is totally quiet. No slipping under heavy acceleration and no bounce marks on the back side of the belt from it not gripping properly. My daycos had a life span of about 4 months before it would start to slip. You're certainly welcome to try them for yourself as they are cheap but I am sharing with you and everyone else here my bad luck with that crap. Dayco rubber just is total trash to me as I have had these same problems on 2 different vehicles both in the belt quality and radiator hose quality.
Rib count does matter but that really only comes into play with belt length, long ones like on semi's have more ribs and small engines like honda sometimes have less ribs. Our truck has a 6 rib belt with a 90" outer diameter (for the XL/XUV platform) and a 92" outer diameter for the standard length like you have.
EPDM is just the material of your belt not the manufacturer. The tensioner should be okay but again it depends on how much tension it is actually applying. When you take the belt off, how much travel do you have to go before you can slip the belt off? If it is a lot then your belt is stretched out and has to go. I still say just to replace the thing with the cracking. With your play in the fan and water pump pulley it sounds like your water pump is failing. When you take the belt off do you have a lot of wiggle in your hand when you rock the water pump side to side and up and down? If you do then your water pump bearings are shot and you need to replace them but for me it would be easier just to replace the water pump while you have it out.
I know some who run dayco belts without any issues but I have had nothing but issues on mine and my dads truck with slipping after a few months of use. Ours I noticed that the black paint they put on the pulleys would wear off on the flat pulleys like our idler pulleys and water pump when I ran dayco belts. When I went to a gates belt there are only very faint scratch marks where it got through the paint on the 2 idler pulleys on the belt drive. It's also weird because the dayco back side would feel very rubbery and tacky which to me is great for a belt but it would squeal real loud when it was like that and my gates belt has a somewhat tacky feeling back but it doesn't squeal. I don't know the real deal with it and am not trying to bash it but just saying my issues I have had with their belts.Sparky said:
As for the dayco hoses the upper rad hose I have is as stiff as a rock and the idiots put a tag right through the one end of the hose instead of a sticker to indicate the model number so I had to try and cover that with the hose clamp and that was hard because it was right at the part where the radiator flared out some and it wouldn't quite seal up there well. Also the hose is as stiff as a rock when its cool where my napa lower rad hose is nice and pliable when hot or cold.
Update. The new belt came today. So I removed the old belt, then started the truck...no noise (no birds chirping). Put the new belt on….still no noise (no birds chirping). Problem solved! So the belt was bad (even though it appeared to be in pretty good shape).
I’m guessing the ridiculous winter we had here in PA did something to the old belt. I first noticed a chirp during the winter when temperatures were around zero degrees/single digits. truck would occassionally make noise after that but not much (at least not until the past 3 weeks or so).
Additionally, the play in the PS seems to have gone away and the play in the water pump appears to be less now. I’ll keep an eye on them, but I’m content for now.
Appreciate the input from you guys.
I’m guessing the ridiculous winter we had here in PA did something to the old belt. I first noticed a chirp during the winter when temperatures were around zero degrees/single digits. truck would occassionally make noise after that but not much (at least not until the past 3 weeks or so).
Additionally, the play in the PS seems to have gone away and the play in the water pump appears to be less now. I’ll keep an eye on them, but I’m content for now.
Appreciate the input from you guys.