drive shaft, rear diff or tranny causing vibration?

[Will I Am T4R]

I've searched but couldn't find with the same issue as mine. The issue started after I lifted the t4r on some 99 talls with 1.5 daystar spacer on the rear I feel it on the floor board and even when touching the hand break it can be felt. Every time I let go of the gas above 30 MHP or so the vibration would start, now it's gotten a bit worst after I swithed the rear coil to an 8 wraps LC. There is a play on the drive shaft when turning back and forth about 1/4 an inch or so. I do have a 2000 ltd 2wd with 165k miles. any help is much appreciated.

 

[Nashvegas34]

I had this happen about 2 years ago, at about 150,000 miles. Basically the connection where the drive shaft meets the U joint in the rear was rubbing, causing some serious vibration just like you described, such as when letting off of the gas. I was advised by a couple of places that I could try replacing only the U joint, but that the end of the driveshaft was also damaged and there was no guarantee that it would completely solve the problem. I chose to replace both the drive shaft and U joint, and it was like new again. Probably because I had become aware of the issue, I noticed another 3rd gen 4Runner on the side of the interstate one day not long after with its drive shaft on the ground in the rear. Apparently they wear out. Aging sucks, except with steak, cheese, and wine.

 

[Will I Am T4R]

thanks I will check the u joint. is the play
on the drive shaft normal? cause I checked on my uncles sequoia and his drive shaft didnt have any play at all.

 

[the great him]

its your universal joint(U joint) its wore out. when was the last time you lubed it? how often do you lube them and what kinda grease do you use?

 

[Nashvegas34]

thanks I will check the u joint. is the play
on the drive shaft normal? cause I checked on my uncles sequoia and his drive shaft didnt have any play at all.

Not an expert but pretty sure not. The drive shaft spins really fast, so any play in it will be felt. The connection should be secure. It's the U joint's job to flex.