Hi all,

I just bough a 2000 Ranger yesterday with 92,000 miles on it. At the time I didn't notice any squeal/chirping coming from the engine.

After I drove it about 20 miles I can start to hear it. And it gets louder/more frequent with higher RPMs. From what the Ranger/Explorer forums say, thats a tell tale sign of a bad harmonic balancer.

With the engine at idle, looking at the harmonic balancer with just my naked eye, there appears to be no wobble or movement in or out towards the engine. The belt tensioner does oscillate about 1/4 to 1/2 inch.

The noise is also much louder on the A-C pump and P-S pump side of the engine. So off comes the serpentine belt. A-C pump pulley feels nice and solid. P-S pulley has a lot of play in it. But when I spin it, it sure feels normal to me. It also doesn't seem to wobble at idle. Granted I don't have a ton of experience with this stuff.

Long story short, I'm going to replace the idler pulley right now. If that doesn't work then I'll go for the Dayco belt. Then the P-S pulley since its a pretty cheap part.

Now the important question. This is the confusing part for me. Are the harmonic balancers as much of a problem on the 4.0 Rangers as they are on the 4.0 Explorer? Most of the info on it seems to be on Explorer forums. And it appears that the part numbers are different between the two models.

Also, I read one forum post about a guy who got a Dorman brand one and his truck wouldnt start after he installed it. So he got a ford brand one and it started right up. Doesn't make sense to me, but can I just go the aftermarket route here? Or do I have to spend $200 on a genuine part?

 

I'm not able to post a picture, must be because I'm a new member.

Heres links to pictures I took of my harmonic balancer. The rubber between the two pieces that make up the harmonic balancer does appear to be dry rotted.

https://flic.kr/p/r5F97R

https://flic.kr/p/r5Kft1

With the belt off, I can't move the harmonic balancer at all. There appears to me absolutely no play.

 

Heres the famous chirp.

Hopefully theres enough detail in this video to diagnose. I can see no play in the P-S pulley and Harmonic Balancer.

https://flic.kr/p/r5FLr4

 

Well, I replaced the brand new looking (can't even find and cracks) Gates belt with the famous Dayco belt. Now the noise is gone. At least for the 30 seconds I ran it when I started it up.

From all the info on the forums, theres a good chance the noise will come back in a hundred miles.

Amazon has a good deal on non-Ford harmonic balancers. Any thought on if I should just go ahead and order one?

 

With the motor off, stick your fingers inside the harmonic balancer. Feel if you can something moving around in there. Like a heavy metal washer or ring. It could be rattling around in there making that noise, In that case, yes, you need a new harmonic balancer. It comes in that one heavy pulley, and it's a major biotch to get out.