Ok,

My sister's 01 4Runner SR5 4WD has a wierd grinding, whirring noise coming from the front passenger side of the engine bay. It's not a metallic whine/loud noise...it's fairly quiet (Have to have stereo OFF to hear it), and it only happens around 30mph. Also, only under some sort of acceleration (usually, although it did happen when I was slowing down to turn into the neigborhood...) If you turn the O/D off, it goes away. I'm pretty sure it's tranny related, but she drives it very nice, and never races it. It happens when the wheels are striaght/turning/whatever, so I ruled out CV joints. Anybody have this problem?? I figured I'll try lubing all her zerk fitting, but have no clue where to go from there. I wiggled everything around, but didn't find anything loose. Any help would be appriciated! Hopefully I've explained it enough!

Thanks in advance.

Brett

 

have you checked to make sure that the fan shround isn't making contact with the fan? It may be close and something little is causing it to make contact.

 

no zerk fittings near there. driveshaft for the front goes on the driver's side.

 

didn't think of that....she just had her t-belt/water pump done a few months back...good thinking! any other thoughts??
Brett

 

my stock answer - check the heat shields around the exhaust - they tend to make noise at different rpm/mph

 

all good...checked that. anything else??
Brett

 

Put in nuetral at the speed it normally makes the sound and see if you still hear it. If you can still hear it in nuetral while going 30MPH, it is probably not engine related.

 

I wasn't really thinking it was engine related, maybe more tranny related. I'll see the truck tomorrow, and take it for a drive again. Any other thoughts guys?? I really am tired of my sister on my back about this one!!
Brett

 

I think I have the same problem, though its just from the engine area in general, not the passenger side. It really only happens for me when I am accelerating fairly quickly (pedal all the way down, I have a manual)

I am just going to not worry about it for now, if anything bad happens I do have an extended warranty.