who put them in? were they used gears? take them back to who installed them and have them fix...if you did it, whats the backlash set at? if thats good reshim the pinion depth and try again...
If they were used gears you could just be SOL and them have a bad wear pattern on them
when gears whine something is not aligned right. I put in used 3.55's in mine but the wear pattern on them was very good and when myself and a friend put them in they had no whine in them at all which is uncommon for used gears but hey I'll take it.
they are used gears, i may be sol and have to wait til i get another 3beans to get some frpp's, gonna have the guy that installed them take a look at them tomorrow. he works for a dealership (but he is actually good) and that has been his sole job for quite a few years, but he did not get to test drive it to see, think he was just in a hurry because he was doin it for me under the table, and cut rate. so he gets to fix it
Its just hit or miss with used gears, I have a used set of 3.55's FMS gears in my car installed by a guy who used to be a ford tech at a dealer and they dont whine. gears are one of those fine line things you dont really wanna buy used unless you have ridden in the car they came from and know they dont whine. some whine some dont its just the luck of the draw
just b/c they wine dosent mean you cant use them though. Id use them for as long as I can before I put down the green on a new set of gears. I mean you really have to botch a rear end job to make it so its to bad to even drive it. The Intall may be ok just that the gears already had a wear pattern in them so they were going to whine regardless
gears are one of those fine line things you dont really wanna buy used unless you have ridden in the car they came from and know they dont whine. some whine some dont its just the luck of the draw
I got lucky w/ mine, paid $100 for them off ebay and they turned out to be in mint shape. I had them for about 3 yrs before I ever got around to putting them in the car, but once I did WOW wasent it nice