[SolidStateS15]

well the rear def shouldn't be making any noise like that. if it needs to be rebuilt it's not something you can do because it's very precise and a lot of shops also mess it up. setting the backlash and adjusting the pinion depth is critical and easy to screw up it seems. i have been the victim myself on this. if this shop really knows what they are doing and you trust them then go for it because that is a good price. ask them how many rear ends they have rebuilt though, or how many each year because if they are not experienced in that then you don't want them doing it. anyone with a wrench can swap out the axle, but rebuilding the diff is a different story.

i'd probably pop the cover and take another look while someone rotates the wheels so you can see what's clicking. that would give you a better idea and us. maybe you could take a video or pics of it.

is it an open or LSD? it will tell you on the sticker in the glovebox if you don't know.

if you can find a good used axle then that wouldn't be a bad idea either. if you can find one off an 03/04 then you can take advantage of the rear disc brakes and loose the drums. you just have to be sure it's the same gearset as your front is since you have a 4wd. you most likely have a 3.55 ratio, which it will also tell you in the glovebox.

 

[SolidStateS15]

there should also be a sticker on the rear axle that tells you what it is, but sometimes it gets painted over or ruined. you have no sticker at all in the glovebox or you can't make it out? it should tell you the gear ratio and diff type.


it's usually easy to tell by just looking at it though if you have the cover off. an open gives you a clear visual of the spider gears and the LSD will have the springs and clutch packs in the middle of the spider gears. if you don't see any springs then you have an open. an aftermarket LSD is usually a more solid looking unit and is mostly closed in so that you cannot easily see any gears.