i tryed looking for this answer.. just curious..
i know my rear is bad.. is makes noises lots of them.. bearing noises.. just waiting for the funds to get a fully built rear...
but recently... ive been noticing a vibration not quite sure where its coming from...
it doesnt vibrate while coasting in gear or decel... only when im accelerating it vibrates...threw every gear... so naturally i drive the car like a pussy now affraid to kill my self if the rear locks up... so i guess my ? is... is this vibration the rear.. or something else maybe engine related... but only under a heavy load such as rear and tires.. ect.. it doesnt not vibrate when not in gear and reved... and i know its not the trans.. BECUASE i just took the bite big time on a brand new one from honda.. (of course wiht a huge discount thanks to my fathers shop at 3200 honda wanted 4400) car has 90k on it

 

Sounds like pitted inner CV cup.

 

i looked at them.. and they didnt seem to bad... i know this mite sound like a dumb question.. but it just popped in my head... is there a front and back to the drive shaft... random just curious...
this vibration didnt occur until i put my coilovers back on.. so im sure that added alot more stress to all the rotating joints

 

When you say you looked at them, you mean you took them off the car and saw that there was no errosion? You can't examine them externally.

Look at this thread to understand what is causing the vibration. This is very well known issue on lowered s2ks. There are 2 fixes available: swap/replace the cv buckets OR half shaft spacers.

https://www.s2ki.com/forums/index.php?showtopic=490050