With the start of all of this cold weather my 01 Cherokee Sport has picked up a squeal in the front end. I replaced my serpentine belt the beginning of December, so the belt is fairly new. The squeal happens for a short time when I start the Jeep, but starts again when I run the heat, and also during acceleration. Also, tonight (not sure if this problem is related) the voltmeter reading dropped to minus 5 (9) and the check gauges light came on. This makes me think that my alternator is bad, but I'm not sure if that would account for the squeal.

This just has me stumped. Any input appreciated

I have the 4.0 L straight six and everything else is stock

Thanks

Scott

 

Dont worry much about the squeal, I have had my belt replaced within a week and now it is down in the single digits. FREEZING COLD. My 98 XJ Classic is starting to squeal but its only bc of the cold. Everything is having to work harder to stay warm so it makes that noise. Next subject. The meter problem is similar to what happend to me couple days ago. My volt meter dropped and was acting funny so I thought it was my alternator but it was my battery, it went dead on me. In this harsh cold weather it will put a whole lot more stress on cold start ups, especially if your jeeps been sitting over night. Can also be a sign of a bad battery that is about to go dead.

 

"Don't Worry" is sometimes not the best advise, the squeeling is telling you something should be checked. I have a 96 that the belt would squeel when turning on the AC, squeel during very damp weather or placing the heat setting to front window defrost, but not when I put it on heat or vent.
I changed belts twice, tightened the belt accounting for stretching. My jeep mechanic friend told me to us AC Delco and not those cross cut style belts. Use the full straight rib style belt. I changed to this type of belt and the noise went away for quite a while except for really damp rainy days. It would squeel at start up until the belt dried out. When it came back after a year, i also looked at the alternator, AC compressor, water pump etc. My guage would drop some when the squeel appeared, so I was looking at replacing the alternator, figuring the bearings were going south.

One day the squeel turned to a metal grind noise and my battery light came on so I fugured the alternater was shot.
I made it to Sears Auto where I work part time for extra cash to have one of my buddies check the alternator. He opened the hood, I started the engine and Power Steering Pump blew, spraying fluid all over the engine.
The squeeling has been my Pump bearings all this time.

So take a look, tighten the belt again and check all the pulleys and bearings the belt comes in contact with. XJ surpentine belts seem to need to be tight!!

 

Ive already checked mine and had my pump replaced completly and two front wheel bearings and fan belt. My belt is nice and tight. So it squeals but it goes away so im not that bent out of shape about it.

 

ANSEWER!!! its your alternator, it has gone bad and when you turn on the ac there is a huge demand in energy and actually creates a short on the alternator which makes the pulley tighten up which creates squaling. and when starting up its the demand to rund the starter selenoid that does that squealing.

I wondere dfor the longest time. then I replaced my alternator from the stock 90 amp to a 170 amp alternator

 

Troth,

Thank you for your concise response. It was exactly what I needed. The only question I have is; Where did you get a 170 amp alternator? If possible could you also supply a part number and approximately what you paid?

Thanks in advance!

 

X2, Although I would not jump in and say the alternator is bad as in troth's case, its a huge possibility worth checking out, but with cold temps it puts more of a strain on the elctrical system especially at start up, so the alt. is trying to compensate, definitely need to have the battery, and alternator checked (load tested). Its free so no one is just guessing.

 

x3.....I had this same problem for a few months.....cold mornings if i turned the defrost on and tried to drive the belt would squeal really bad and the volt gauge would drop sometimes almost to 0.....My thought was alternator or battery....I put a new battery in it still had the same problem...after talking to a buddy of mine we ended up replacing the battery cable ends and cleaning the connections at the alternator(we pulled it and it tested good).....put it back together and tightened the belt up real good(I thought it was tight when i changed it but we tightned it even more) and since then I have not had one problem....check all your connections and grounds

 

I would be very careful with tightening other than OEM specs. in the user manual, there are belt displacement specs to follow. over tightening puts a HUGE strain on the bearings of water pump, idler pulley, alternator, oil pump, power steering etc. I just blew the bearings of my water pump, and its not fun!
as far as the 170 AMp, no part number, but its powermaster. It was kind of a fiasco. I recieved it with a V belt attachment on it and had to ship back and fourth a couple times. then I also had to modify the mount bracket and part of the block

 

Weird my USFS 96XJ's alternator came with 170A on it.
My old "civie" XJ's had a 90A on it.

 

How does it effect the oil pump?

IIRC the belt doesn't have any contact at all with the oil pump...

 

Went to the boneyard and got a 117 amp (stock for my 99) and a 136 amp from a dodge. Ended up with the 117 since the connectors were different on the 136. When I pulled the old one there was built up black dust from the belt packed all around the pulley and the shell of the alt. Due to this I feel pretty certain that your diagnosis was accurate. New alt is in and zero squeal!! Even when I had everything on, wipers, lights, heat, rear defrost, rear wiper, radio, dome and hazards she ran quiet with minimal voltage drop.
I also picked up the tie rod assembly from a 96 ZJ and looked at every 4.0 in the yard for an uncracked exhaust manifold and no luck. On my way out, lo and behold, there lying on the ground was one, a newer style with the accordion style sections to absorb shock and prevent the cracking! $73 bucks total!

 

Yeah. Something is not coping with the load well. hope the new (er) alt fixes it.

Could be bearings in anything serp touches. Mine was a failing ac clutch bearing. Would squeal on start and hard accel. Eventually it locked up.

Good luck, hope you've fixed it!

 

I had a very similar problem. when the Jeep was cold and turned on defrost i would get a squeal. after engine would warm up or i got to about 50mph the squeal would stop.

then one day i lost all power and car died and wouldnt start. had it towed in battery and alternator replaced.

problem was fixed, no squealing for about a week. now the squeal is back. any ideas? could something me causing the alternator to go bad?

 

Is it a new belt? If not, its possible that you have your belt too tight, causing the bearing to fail prematurely. Also if its a rebuilt alt., it could be that the bearing wasn't replaced. I've had brand new parts go bad within a couple of weeks, before. It could also be another bearing/pulley going bad.