Whats up guys. I have been lurkin around here for a while and figured some of the experts here might have an idea about this. I have a 2001 extra cab 4wd tacoma v6...it's pretty extensively modified:

http://www.esbfabrications.com/ryan.htm

Anyway when I brake, and the forward weight transfer occures, this loud rattling sound happens from under the truck...having many people listen to it we have all determined it is coming from the tranny or transfer case. It only does it when braking, and seems to slow down as the truck slows down. no noise in acceleration or idle, just stopping. I changed to a new drive shaft support bearing, whole new driveshaft, tightened all the bolts on the driveshaft flanges, greased the slip joint and nothing has worked to stop this, so thats one of the reasons I believe it to be coming form the tranny area. The clutch is less then 25K old. I have blown up rear ends before and this is not a rear end thing I am sure. The 4wd has been removed, but the transfer case is still there obviously. The truck runs and shifts fine, at this point it's just a really annoying and scary noise. Any ideas? Suggestions are very much appreciated.

-Ryan

 

Is it possible that the chain in the tranfer case is worn and it's slapping the inside of the case?

 

Yes I would assume it's possible. I can replicate the sound to an extend by moving the shifter in and out of the different gears when stopped, so I think it's something with the gears in the tranny. But I would think if there was something wrong with them the truck wouldnt shift good or drive at all.