93' 4x4 pickup with the 3.0liter V-6 3vz-e motor. i have located where the noise is coming from. when someone sits in the passenger seat the floor board touches the top of the transfercase so whenever there is movement from accelerating or braking the floor board flexes and touch's the top of the transfercase creating vibration. its been high centered on the cross member twice. i dont think that its pushed the transfercase up because when i drive with no passenger it makes no noise at all. so how or what can i do to stop it from touching? thanks!

 

you might have tweaked your frame or it could have pushed the case up id actually have to look and see for myself to get a better understanding of how and what to fix

 

Might also check the cab mount bushings on the passenger side. Maybe one or more of them has ripped or had the rubber separate from the steel surround and that lets the cab settle downward with the added passenger weight and that is causing the noise.

 

Mine does the exact same thing.. But my cases have been clocked and tucked up high so I have less than a 1/4 inch of clearance to the floor board.. I was going to put a 1" BL on mine or beat the floor board up a little..If your truck is stock id look under it with someone setting in the passenger side and see how close the floor is to the t-case. Sounds to me like the t-case is twisting more than normal under load..During acceleration the passenger side of the t-case rotates up a tad.. id check the mounts

 

ok so bad mounts or bushings would have cracks in the rubber? i had a friend sit in the passenger side and it was about an 1/8th or 1/16th of an inch from the t-case. i was thinking about getting a BL too but i dont want to just push the issue aside if its something more then bad mounts or bushings. my rig is stock but i wheel it alot so hopefully all it is, is just worn out bushings.

 

Yes, look for rips where the rubber is torn away from the steel shell:
- http://www.4crawler.com/4x4/ForSale/...l#PolyBushings

Same thing on the t-case and motor mounts.

 

Get skinnier friends...LOL sorry couldnt resist

But I am thinking worn out bushings also!

 

hahaha! that was good one! nice rig!