have problems with my Diff, need experienced diff experts to chime in.

[c32c7]

I bought an ATS carbon 1.5 way LSD, took it to a shop to be installed. 3 months later, my car started making a humming sound. I took it back to them and they said that the gears (pinion and others) are not worn out due to the LSD putting extra stress on "high milage" gears. of course there were never sounds of such before the install.

however, after speaking to my buddy at another shop, he tells me that theres is NO WAY IN HELL that the LSD would cause gears to get worn if the LSD was installed right. He says that he fixes bad LSD installs all the time. To properly install a LSD, the install needs to adjust the backlash with some type of blue stuff (i forget what he called it) and a micrometer.

during the install, I did not witness the measuring or testing of any sort. the shop that installed it says that its because my gears are high milage and their suggested solution is to obtain a low milage pumpkin to replace the one i have. my friend suggests that this is ridiculous.

another mechanic friend of mine told me that if this continues, there will be some serious problems to come. the shop that installed it told me that it would not damage anything, just get louder.

can someone verify the validity of either statements? what actions should be taken? Thanks!

[tiger]

you know that they hum all the time, don't you? or is it a different kind of hum... they are kind of supposed to "sing" when you're driving.. with every gear up , the humming is more high-pitched. Is it doing that?

[hudy]

It sounds to me like your friend is right about pinion depth being set incorrectly. As long as the gears aren't worn too badly, see if he will set it up for you.

On a side note, my diff has been making noise for about a year now. The pinion bearing is roaring. I just haven't had the patience to take it apart and fix it.

[navysnail]

yeah, your friend who was talking about adjusting backlash (preload too) and all that stuff sounds right. you can download a FSM and see if you can be present when it is done