replacing differential

[maxst420]

how hard is it to replace the differential from stock to a posi unit on the 7.5\" rearend from an 89 s-10 4.3 4x4

[bratass]

If you are talking complete housing not too hard at all.Undo brake hose and e brake cable-unbolt driveshaft torch old u bolts and shocks or unbolt and she be free to roll right out the back http://www.s10v8.com/images/smilies/icon_wink.gif Next roll new unit into place install new u bolts and shocks reconnect all brakes and bleed/adjust replace driveshaft and fry the tires a couple times http://www.s10v8.com/images/smilies/icon_biggrin.gif. If you are talking guts you might want to hire it done because the tools will cost almost as much.

[maxst420]

no i mean replacing the actually unit inside

[BrandOmatic]

there is a right way to do it and the way a lot of people probably do it. the right way requires at least a dial indicator w/magnetic base, an inch pound torque wrench, pinion holding tool, and a press and bearing drivers if you\'re installing new bearings/races. the other handy tool to have is a pinion depth checking tool to see whether your pinion shim(s) has put the pinion at the right depth in relation to the housing, and ultimately, the ring gear. I was fortunate enough to have all this stuff to use at school when i installed my auburn.

The way a lot of people probably do it is simply re-using the old shims and such, and hopefully at least using a dial indicator to set the correct backlash, and checking the outcome with gear marking compound. After knowing what i know now about differentials, i would never try to install a unit or new ring/pinion without these tools, but that\'s just me.

so to agree with bratass, it would be wise to have one installed by someone who has all these special tools and the know-how.