Hi. I have an '01 Dakota 2wd with a 3.9L. My truck has about 85k miles on it and I just had a new water pump installed. The mechanic did not change out the serpentine belt when he did this job, and I found the belt squealing badly aftwards. I bought a new, higher quality belt, and installed a new idler bearing in the rigid idler while I had things apart. Installing the new belt helped immensely, but the belt still lets out a couple of chirps, especially when cold. I inspected everything else - the new water pump, the PS pump, the AC compressor, and the alternator, and everything turns freely and smoothly. The only thing left that I can think of, is the spring loaded tensioner spring may have gotten weak over time, or when the water pump went.
My questions are: Is this a common thing to happen on these motors? Do these idler assemblies need to replaced regularly, or can the spring tension be increased some way? Is a NAPA idler assembly OK, or is there another brand that is better/stronger?
Thank You!

 

i'm dealing with a similar situation now...here is my thread on the subject. I'm thinking my clutch fan is the problem now.

https://dodgeforum.com/forum/2nd-gen...y-bearing.html

 

I had a bad squeak like that on my truck too, at 42,000 miles. The belt also kept slipping off the pulleys. I replaced the belt and still had the problem. The tensioner was bad. I replaced it and it has been fine ever since then and I have almost 143,000 miles on my truck now.

There are no adjustments for the tensioner. When it wears out you have to replace it. Check the movement of the tensioner-with the engine off if you can move it more than half an inch by hand it's bad, and if the tensioner moves more than that when the engine is idling the tensioner is bad. Belts will sometimes squeal for a few seconds when the engine is cold, but a continuous constant squealing indicates a problem.

One other thing, get the tensioner from Napa or the Dodge dealer. I tried 2 tensioners from Auto Zone and neither one worked. The belt kept sliding off the pulleys. Then I looked at the Napa website and compared their tensioner to the Autozone one and my original tensioner. I finally realized the Autozone part was not built the same and did not look the same as my original tensioner. The Napa tensioner cost twice as much, but it worked fine, and is still working fine now, over 100,000 miles later.

Jimmy

 

Thank You, both. I will go buy a NAPA tensioner and install it. If that does not cure it, I will move on to the clutch fan. The tensioner assembly is cheaper and easier to install than the fan clutch....
After searching this forum, I see that it is quite a common problem with these motors. I would guess that the spring gets corroded and weak with time. I do not want to ruin my new belt, so I will try to get the tensioner replaced tomorrow.

 

If the fan clutch is bad, you will know it. The engine will howl and roar like a jet plane on take-off as you are driving and the truck will bog down a bit. It's normal for the fan clutch to engage when the truck is driven for the first few hundred feet after a cold start. When the clutch stays locked up while driving, you need to replace it. An easy test for the fan clutch is to try to spin the fan by hand, with the engine off. The fan should move a few inches easily by hand. If it is stiff to move or won't move at all, the fan clutch is bad. I found out the hard way that it is best to get a new fan clutch at the dealer, or a low-mile used one at a junk yard. I replaced mine back in February with a fan clutch from Autozone, it was OK until the weather got warmer in the Spring. Then it would howl like a banshee and would lock up after idling only for half a minute like at a red light or drive-thru window. It would stay locked up for a long distance too, it would take a mile or so of gunning the throttle to get it to loosen up. A new fan clutch costs $115.00 at the Dodge dealer here. I bought one off a wrecked Dakota with about 75,000 miles on it at a good You-Pull-It junk yard for $30.00. It has been fine since I installed it back in June. If and when it ever goes bad, I will just get a new one at the Dodge dealer. The Autozone Store Manager was very good about the return on their fan clutch, he gave me a full refund in cash, even though the part was 5 months old.

I would think the problem with your belt is the tensioner. The tensioner spring does get corroded and weak with time and wear. I also had to replace my idler pulley, that one started making noise at about 70,000 miles. I used a Napa part for that, it worked fine and is still doing fine now.

Jimmy

 

Thanks, '01, I will give my fan a spin by hand when I get out of work today. I have heard it get loud when it is very cold, but it does not stay that way for long so I believe that it is operating normally.
I have already cleaned my pulleys, and checked and replaced some of the bearings, even though they were not bad. This (tensioner assembly) really seems like the only thing left. Even though it seems to work and move OK, I suspect that it is just weak.
BTW - I have found that belt dressing generally does not help (for long, if at all), and only succeeds in making a mess, and it can build up in the grooves of the sheaves and cause more problems than it solves. It may work OK on standard V-belts, but I do not like to use it on the micro-v belts. JMO.

 

Well, I can report that our spring loaded tensioners do, indeed, get weak over time. I purchased a NAPA tensioner (part # 38116 complete with pulley, $73.19) and installed it. As I was installing it, I could definately tell that it was significantly "tougher" to pull in than the OEM unit I had removed.
My squeak has been erradicated, and I am Happy!
Greg

 

well i found the source of my squeak too. After a new tensioner and an idler pulley, I went to put on a new clutch fan. After I pulled the old one (before putting in the new one), I started the engine to see if that was indeed the problem. Still the darn squeak. So on a whim I grabbed my old belt and put it in place of the new one, sure enough, no squeak. So my NEW belt was the problem the whole time. I'm going straight to Advance Auto and getting my money back on this POS.

 

Glad to know both of you guys got the belt-noise-tensioner problem solved. It's good to have the forum community here so we can help each other out.

Jimmy

 

I'm dealing with the same thing on my 02 3.9 with 125,000, mostly on cold starts, just some squeaks though. Last night I also noticed that the fan was not shutting itself off, it was on the whole time. It's like 20 degrees here. Something is up with it, I'm thinking the fan clutch because it is really loud like someone else was saying.