2001 Mountaineer strange sound

[5L_Mounty]

Hi guys. I am new here... normally I do not join the forums for cars that I own, however I can't for the life of me find any threads specifically dealing with the noise that I am experiencing. It most likely will be related to one of the many threads that I have read, but just wanted to see if anyone can help me diagnose the issue to confirm. Any help is much appreciated... so this is what I have; first, my truck is a 2001 Mountaineer with a 5L & AWD. What happens is, while accelerating at (very specifically and ONLY) 1/4 throttle, and only have been able to do it while the truck is in first or second gear, about a one-second chirp or squeal sound. It literally only lasts for approx. 1 second, no matter what. It will not do it in park (or neutral) while revving, nor have I been able to get it to do it while in 3rd or 4th (OD) gear (which may be coincidental). Any ideas at all? It sounds like a belt squeal, as if a pulley were locking up for a second... happens with the A/C on or off, makes no difference. The only reason that I have not pulled the belt off to listen is because it only ever happens while moving, and I don't want it to heat up and blow a head gasket or anything. I am thinking that I may have to wait until the sound is more prevalent or happens more often (or worst case, when something fails)... but this is my DD and I need it to be reliable and I do not like worrying if I am going to get stuck on the hwy somewhere and have to deal with towing and BS. I can take a video from in the truck and post it if anyone thinks it will help. It will do it on command, so that is not a problem... 1/4 throttle, and at some point throughout 1st or 2nd gears, and "chirp" real quick and then gone... will not do it again until another acceleration through either 1st or 2nd.

 

[koda2000]

My 2000 Mountaineer 5.0L AWD also make a squeak/chirp noise, but not while idling. It's not the cam synchronizer (which can make a bird-like chirp) and it's not any of the tensioner or idler pulleys (I just changed all 3 of them, because they were all worn) and it's not the A/C clutch pulley (which I also just replaced, because it was ready to fall apart). So that pretty much leaves the water pump bearing, or the alternator bearing, I'm planning on replacing the W/P shortly as I'm pretty sure it's the cause of my squeak (plus I can see the W/P pulley wiggling a little bit when the engine is running and can feel a little play in the bearing). I already have a new pump in the garage ready to go. I usually do my own repairs, but I asked a mechanic friend of mine what he'd charge me to replace the W/P and he said $125, which is well worth it. It's a miserable job on the 5.0L engine.

If you remove the belt and spin everything by hand it will help you to narrow down the source of the noise. Everything should spin smoothly and quietly. As long as the engine is cold, you can run it for a few minutes w/out hurting anything.

 

[5L_Mounty]

My 2000 Mountaineer 5.0L AWD also make a squeak/chirp noise, but not while idling. It's not the cam synchronizer (which can make a bird-like chirp) and it's not any of the tensioner or idler pulleys (I just changed all 3 of them, because they were all worn) and it's not the A/C clutch pulley (which I also just replaced, because it was ready to fall apart). So that pretty much leaves the water pump bearing, or the alternator bearing, I'm planning on replacing the W/P shortly as I'm pretty sure it's the cause of my squeak (plus I can see the W/P pulley wiggling a little bit when the engine is running and can feel a little play in the bearing). I already have a new pump in the garage ready to go. I usually do my own repairs, but I asked a mechanic friend of mine what he'd charge me to replace the W/P and he said $125, which is well worth it. It's a miserable job on the 5.0L engine.

If you remove the belt and spin everything by hand it will help you to narrow down the source of the noise. Everything should spin smoothly and quietly. As long as the engine is cold, you can run it for a few minutes w/out hurting anything.

Thanks for the reply... That was all of the things that I found, and suspect that it is going to have to be one of them... but being that mine only does it in that very specific instance, it is quite tough to nail down. Also, something I did not mention, as I was already long winded enough as it was, is that I have pretty recently replaced my water pump, 2 idlers, tensioner, belt, and alternator. And you are right, the W/P was a ******* and a half to do... but I at least converted to elec fan at the same time

 

[5L_Mounty]

UPDATE: Video link below. You will hear, shortly after taking off (at the aforementioned 1/4 throttle) and the truck going into second gear, the "screech" lasting about 1 second. This was on my go pro, inside the truck, and windows UP. Thanks again

 

[koda2000]

Sounds more like a little bit of belt slip to me. Have you replaced the belt and tensioner?

 

[5L_Mounty]

Sounds more like a little bit of belt slip to me. Have you replaced the belt and tensioner?

Yes, please see post #3... does sound like belt slip for sure

 

[koda2000]

There are index marks on the belt tensioner body. A properly tensioned belt will have the pointer somewhere between these marks. I've read here on the forum that different manufacturers/auto parts stores indicate 2 different belt lengths to be correct for Explorers. They lengths are very close, but one is a little bit longer than the other. This extra length can lead to a belt which is improperly tensioned and which may be prone to slipping and may cause the tensioner to clunk on its stops. I don't know what the part numbers for the different belts are (usually the last 3-4 of the part number digits indicate the overall length). I've replaced all my 5.0L serpentine belts with belts from AutoZone (Dayco brand I believe) and have not have any problems with them.

 

[5L_Mounty]

There are index marks on the belt tensioner body. A properly tensioned belt will have the pointer somewhere between these marks. I've read here on the forum that different manufacturers/auto parts stores indicate 2 different belt lengths to be correct for Explorers. They lengths are very close, but one is a little bit longer than the other. This extra length can lead to a belt which is improperly tensioned and which may be prone to slipping and may cause the tensioner to clunk on its stops. I don't know what the part numbers for the different belts are (usually the last 3-4 of the part number digits indicate the overall length). I've replaced all my 5.0L serpentine belts with belts from AutoZone (Dayco brand I believe) and have not have any problems with them.

That is great information... Thank you! I didn't even consider that, but it makes perfect sense... That said, I just went out and looked, and of course my luck, there are no markings on my tensioner that show the range... so I went looking, and you were right, there are several belts listed for the truck. I have the 93.5" on mine, but I also see a 93.8 and a 94.0 listed. Unfortunately, my old belt was worn off and dry rotted, so I threw it away when I replaced it... wouldn't have been able to read it, but I could have measured if I had known. Now, to find a way to test the theory... may be buying two belts and returning at least one of them! I'll update with progress so anyone reading this in the future will have the info and not have to hopefully go through this!

 

[koda2000]

If you already have the shortest belt (93.5) the other two, which are longer, can only make the situation worse. My AutoZone shows the Dayco belt is 93.5". So that doesn't seem like your problem. Have you ever spilled anything on your belt (like antifreeze or oil)? W/out index marks, the only reference you have is that the tensioner should be in about the center of it's travel with the belt on. Maybe you got a bad/weak tensioner?

On this Motorcraft tensioner you can see the index marks...

 

[5L_Mounty]

If you already have the shortest belt (93.5) the other two, which are longer, can only make the situation worse. My AutoZone shows the Dayco belt is 93.5". So that doesn't seem like your problem. Have you ever spilled anything on your belt (like antifreeze or oil)? W/out index marks, the only reference you have is that the tensioner should be in about the center of it's travel with the belt on. Maybe you got a bad/weak tensioner?

On this Motorcraft tensioner you can see the index marks...

Again, thank you! Very helpful... At least as far as figuring out the belt and tensioner situation and relationship. The bad news is, I don't think I'm any further along in diagnosing it. I was able to crawl under the front and see the travel area of the tensioner. It sure doesnt appear to be too long or short of a belt at all... So I started it and sat there staring at each pulley for at least a minute a piece, trying to find anything that looked even arguably abnormal. Nothing. Going to yank the belt off in the a.m. and take it for a spin. Have to figure this bs out before it makes me insane. Ugh

 

[5L_Mounty]

2 UPDATES: #1 - Will not do the noise when cold. #2 Got it to do the noise under full throttle and NO throttle today... and lucked out enough to catch it on video (below). Note -you can actually tell that whatever it is held the truck back as the sound was made, and then came back strong. Still have yet to pull the belt and drive it, because it was damn 40* this morning! Like I said though, when I DID drive it this morning, I could not get it to do it while cold... so it wouldn't have made a difference anyway. Most certainly sounds like the belt making the noise though.

 

[5L_Mounty]

Ok, another update... Got it to do it while revving in park with hood up and staring at pulleys. Still sounds like definitely the belt making the noise. Nothing out of place as far as pulley movement or stoppage or anything like that. Starting to think it's the bearing in the god damn water pump. Gonna have to either replace idlers one at a time, then tensioner and rule those all out that way (since they, along with the water pump were all replaced at the same time)... And then move on to the water pump... OR... wait for it to start making the noise more of the time or wait for something to fly apart on me. Can't think of another way to narrow it down.... Really don't need to get stuck(cause that is when it will happen to me) while I'm on the road on my way to a job. This blows

 

[koda2000]

Remove the belt and check the feel of each pulley bearing by hand before you do anything else. Bearings don't sound the same as a belt slipping. Squeak vs squeal.

 

[5L_Mounty]

Remove the belt and check the feel of each pulley bearing by hand before you do anything else. Bearings don't sound the same as a belt slipping. Squeak vs squeal.

I have done... and I swear when I tell you everything feels absolutely perfect, I mean perfect. It's so strange. I have put nearly 1300 miles on the truck since I first heard it, and it has never yet done it one single time while idling or driving using (my) normal throttle pressure.... Which is light, MOST of the time. Lol. I mean, you would never even know it did it, IF you never pushed it a bit or sat there revving it like a jackass, trying like hell to get it to do it. And, sitting there hearing it several times while looking under the hood, I can't rule out the squeak vs squeal entirely. It is LOUUUD when right on top of it. When it comes, it's almost impossible not to jump.

 

[98 MERC]

I dont know man.I watched the video like 5 times.You sure your torque converter or trans ain't slipping ? I can clearly see almost like a slip in the RPM gauge.I mean i have driven vehicles with slipping trans it sure looks like a slip.You can indeed see something holding it back while the gauge drops slightly and then picks up.You done fluid and filter lately or checked the level or fluid quality ? Any shavings in the pan ? I also can hear the sound clearly inside your vehicle.Like its right under you.Not it front by the pulleys.Hows your transfer case ? you change the fluid ?

 

[5L_Mounty]

UPDATE - FIXED: Finally, I was able to figure it out... and Koda, thank you again. Sorry I haven't been able to update while diagnosing lately, but on Saturday morning, I was able to fix the issue. I figured it out on Friday, after work with the help of a buddy... I'll have to spare most of the details of how I got there, as I am working and don't have much time, but it ended up being the cam synchronizer. After doing a bunch of reading, and if I remember right, it was one of Koda's posts from a while back that allowed me to fix the problem without replacing the part! I got a new cam pos sensor, and took it all apart and cleaned it good, lubricated the shaft with some Royal Purple Max Gear 75w90 (Koda said that he used Trans fluid IIRC) that I had from a recent trans fluid replacement on my 6 speed Maxima that I had leftover... About 4 drops of it down the shaft hole, replaced the cam sensor, and bam, no more noise! I put over 330 miles on the truck this weekend, and previously, the longest I ever went without the noise was about 7 miles... and I drove it fairly hard all weekend, too. Very pleased with the outcome. Now I can finally focus on posting my "refurb and dye" seat project job that I just finished for the old girl

 

[koda2000]

UPDATE - FIXED: Finally, I was able to figure it out... and Koda, thank you again. Sorry I haven't been able to update while diagnosing lately, but on Saturday morning, I was able to fix the issue. I figured it out on Friday, after work with the help of a buddy... I'll have to spare most of the details of how I got there, as I am working and don't have much time, but it ended up being the cam synchronizer. After doing a bunch of reading, and if I remember right, it was one of Koda's posts from a while back that allowed me to fix the problem without replacing the part! I got a new cam pos sensor, and took it all apart and cleaned it good, lubricated the shaft with some Royal Purple Max Gear 75w90 (Koda said that he used Trans fluid IIRC) that I had from a recent trans fluid replacement on my 6 speed Maxima that I had leftover... About 4 drops of it down the shaft hole, replaced the cam sensor, and bam, no more noise! I put over 330 miles on the truck this weekend, and previously, the longest I ever went without the noise was about 7 miles... and I drove it fairly hard all weekend, too. Very pleased with the outcome. Now I can finally focus on posting my "refurb and dye" seat project job that I just finished for the old girl

Glad to have helped. I "oiled" the cam sync on my daughter's 2000 Mountaineer 5.0 about 2.5 years ago and it's been quiet ever since. I knew the cam sync was the source of me "chirp" when I placed my mechanic's stethoscope on it (great tool for finding engine noises BTW). From your description of your noise I wasn't of the opinion the cam sync was your problem, but apparently it was.

Re your seat project - I don't know exactly what you're fixing, but I recovered the bottom of the driver's seat on my '01 EB. I bought a new leather bottom cover from theseatshop.com (they also sell replacement foam). the new cover was a perfect match to OE and they were super helpful. I'd never done anything like this before, but it was pretty easy after watching their video and turned out great. They even told me how to clean the rest of my leather so that everything matched.

BTW, I had the water pump replaced on out '00 Mountaineer AWD last week and my squeak is now gone too.

 

[5L_Mounty]

Yes, thanks again Koda... Still going strong with no issues... and I'm up to about 375 miles now with no return of the noise, so I'm confident that it's taken care of at least for now.

About the seats, I appreciate the info about the seat shop. I will hang onto that for sure! I was going to post a new thread on it, but remembered that you have to pay (for some reason) on this forum to be able to post pics... which I am not going to do... I was thinking though, since you can post a video link, I may just do that... I think what I did may actually help people out, so I like to share if I can... The deal was this; my Mounty is in EXCEPTIONAL condition with the exclusion of the 2 front seats, which were really in a bad way. I went out to the local junkyard (aka my home away from home), and found a 99 XLT Ex out there with near perfect, just dirty, leather seats in it... but they were medium grey, and I have Med Prairie Tan interior... so I ordered everything that I needed, which I have done many times in the past (before cameras were attached to us, so I didn't document it), and prepped and dyed the seats my color. They came out absolutely great. So much so, that you literally can't tell by looking or feeling them. Made my truck look like a million bucks in comparison to how it was with the cheapo seat covers I was rocking.

 

[koda2000]

BTW, You can post pictures w/out paying if you upload them to something like PhotoBucket, then copy the IMG and paste it into your post.

 

[5L_Mounty]

****, thanks again! I'll do that