hypforlife32

hey guys, i think i posted something a while back about this but im not 100 percent sure. well to start my story i ended up selling my stage 2 diff back to puddy in exchange for a reconditioned ap1 diff out of his personal car(great guy). i had NO vibration before this at all and no weird (hair dryer on low sound at about 5-7% throttle positioning( just estimating). So i removed the diff and installed the ap1 diff and the first thing i noticed was a weird hair dryer sound that i talked about that was never there before i even had my stage 2 in my car. my factory diff never had this sound, and neither does my friends 04 ap2. I also drove his dads 05 ap2 and still this sound is none existent in their cars. Also on top of that there is a bad vibration in every gear almost when i hit the gas under almost any kind of load. its just getting worse and worse. is this my axles or the diff? i dont know and im not sure how to tell. i also changed back to my ap1 wheels the day after i swapped the rear ends and i thought that may have been in but i put my ap2 wheels back on and its still there. im stumped. any help would be great, thanks. im at 80k miles as well.

s2cho

my guess is the diff is bad, or the install went wrong but i dont know how the install could go wrong,

do you know if the oil was gear oil 75w-90 or 75-w125?
or did the installer put something else like regular motor oil..... could happen...

and my last best/guess is that its under filled or overfilled. jack the back up and take the
filler bolt out and then put a oil pan or something and set the car fully down
and see if any gear oil comes out. if any comes out means too much oil

if nothing comes out try to put some more oil and repeat. means not enough diff oil.

im guessing theres not enough oil if its sounding like a hair dryer.

sorry im not positive in any of this.. but doing this cant hurt

oh sorry your the installer LOL >_<

hypforlife32

i did all of the work myself, i installed my stage 2 with no problems at all. the oil is amsoil 75w-140 which i have used before and puddy told me was perfectley fine. i filled the diff up when the car was dead level sitting on the ground and i over filled it a little bit and let it drip/run out for about 20 min until it stopped.

s2cho

how long have you drove on it?
and any launches or pulls?
and 75w-140 is great.

and if you say no to any of those... i would yell at the guy that gave you the diff and
tell him its effed up and that you want yours back or that he should fix it

hypforlife32

ive drove on it for maybe 1k miles, and zero launches. ive done some pulls, the pulls vibrate bad and just seem to get worse and worse, like its very uncomfortable to go above 5k rpms, and just even pushing the gas to the floor in 4th of 5th at 40-50mph is crappy.

fatjoe10

try removing the driveshaft from the diff, turning it 180 degrees on the pinion and reinstall it. Sometimes this seems to cure vibrations, specially after drivetrain component replacement.

hypforlife32

ahhh okay, i hope that helps. i was thinking it may be something like that. i will try that tomorrow morning, thanks!

S2KPUDDYDAD

Hey give me a call today....the rear was mine from my car and ran just fine in my car. It Is bone stock and had maybe a few thousand miles on it with no hard use.

It is posable a bearing is going bad and is causing the sounds/feeling you have or it just maybe an axle?? Hard to say.....

Anyway, you are welcome to send the rear back and I will go through it to see if I can find an issue. It's strange that the rear is causing the problem since it was fine in my car but, strange can happen and if the rear has something wrong I will take care of it right away for you

hypforlife32

Okay puddy I'll give you a call in a little bit thanks!

hypforlife32

Okay puddy I'll give you a call in a little bit thanks!