05' 4.7 with only 35k original miles. Noticed when the engine in idling and looking at the fan spinning from the side it looks there is a slight constant wobble. It appears at certain angles it may be the fan clutch with an even more slight wobble to it.


I did put my finger back inside the fan clutch while pulling/pushing on the fan and can detect maybe 1/32" of front to back play between the main clutch body and the hub it spins on. Could that be the problem? There is no side to side play whatsoever, it's more that I can slightly move it in and out on the shaft.


What say you guys? How does your fan look when it's spinning? Can you feel ANY play in your fan clutch?

Am I being overly cautious? I figure with this low of miles that the fan clutch shouldn't already be wearing out and the fan shouldn't be warped.

Thanks!

Is it bolted to the water pump? Could the water pump be failing? I dont own a V8

Thankfully not, my concern level dropped to almost zero after finding this out. The water pump is driven off of the timing belt and completely isolated from the serpentine belt drive assembly.

So upon looking it over again from cold, it runs straight and true for about the first 20 seconds and then I hear the vacuum air pump under the manifold make a quick suction sound which then drops the RPM's slightly and that IS WHEN THE FAN STARTS TO WOBBLE.

I'm thinking the fan clutch is unlocking at that point and then causing the wobble condition to occur?

Not sure? Any thoughts on this would be appreciated!

Hard to know - if you can get a video might be helpful. I’ve had an 03 and an 08 and the fan always seems to make noise on mine when the hood is up like it’s catching up something, but I never see anything obstructing it.

It's slight, the guy at Autozone said he wouldn't even mess with it if it was his. The Duralast that he brought out had about half the cooling area/fluid capacity as the OEM. I just ordered Aisin FCT075 fan clutch and will update when I install it in case anyone sees this thread in the future and could use it as a reference.

A little off topic, but how did u end up with a 2005 with 35k....would love to hear the story.

I was walking my dog a couple of blocks from my house and it was sitting in the driveway having been backed out of the owner's garage. I'd never seen it before and asked the owner who was working in his garage if he'd like to sell it. He said, "sure." It was his ex-wife's who never drove it anywhere except the store. I'll have to post a thread about it, it's like a time capsule.

Notice it's spinning straight until about 30 seconds into the video when the RPM's drop.

2005 V8 4Runner Fan Wobble - YouTube

I don't think there's anything wrong with it, mine does a similar thing as well.
It's probably the the fluid release once the thermo spring heats up that's causing a bit of uneven centrifugal force.

Thank you, that's exactly what I was hoping for, a confirmation that I don't have a grenade waiting to go off sitting on the front of this engine.

Yea - it looks like it’s doing it’s job. It sounds a little choppy, I would have noticed it too, but doesn’t seem like anything to worry about. Just check the serpentine belt too to make sure there’s no grinding or issues there