I can't pinpoint where it's coming from, but when the cooling fans come on it vibrates the car. The car idles perfectly smooth until they come on. I've recently replaced both fan motors, made sure everything is bolted tight, and nothing is hitting the fan blades when their on. I get the feeling something is hitting the frame of the car because you can feel it throughout the car. If anybody has any ideas on this it would be greatly appreciated.

 

Are the fan blade assys. balanced? If theyre not balanced or a blade is missing itll vibrate like hell when it comes on. Check them to make sure.

 

I'll try that. Should I take the fans out and put them back in or is there some other way to do this?

 

Probably make sure there is nothing interfiering with them like you said above and make sure theyre secure. After that, give the fas assemblies a good visual inspection, either on or off the car. If one of the fans seems to sort of ocillate like a pendulum about one point after its nearly stoped rotating then thats a good sign that its out of ballance. You could also (carefully) spin each up with a hand drill and see if one begines to vibrate when it picks up speed. From the way you described it, though, the problem should be able to be seen if its causing vibrations that bad.

 

Make sure that the bottom two bolts didn't come out. They don't go very deep and if they come out your fan will shimmy like no other. Just crawl on your back and look up and feel for them. There should be an bent aluminum line that shares the driver side bolt.