i know theres quite a few threads on this but i couldnt find anything helpful yet. When i accelerate from around 5 mph to 40 mph, i hear a loud whining / whistle noise in the back. it only makes the noise when i give it throttle, not when im coasting. once i accelerate at a faster rate in the highway, the sound just disappears too. i changed the rear diff oil about 5000 miles ago with amsoil and out of no where it starts happening. the car is lowered about 2.5 inches so would it be my axles? is it either my axles or diff going bad? car has 59k miles

 

Is the diff stock, the only whining noise I've ever heard from the diff is when my buddy went 4.77s and it had a loud whining noise(which he hates). Either that or your diff hate you for all the hard lunches you'll made it do My s2k is drop 1.5inches and I've had no problems, I've heard of no problems with 2+inches drop s2ker with noise other than tons of scraping

 

if you are lowerd you might want to check your propeller shaft (driveshaft) it's the one that runs between the tranny and differential. sometimes when you're lowered, depending on how low, you'll need spacers there to keep the ends straight.

 

i never launch my s2k since its my baby :0) the diff is stock. i had the car at this same height for over 15k... do you think it would take this long to make the driveshaft wear down or make it to eventually cause noise?