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DISCUSSION => Engine + Driveline => Topic started by: mtle30 on February 17, 2012, 03:22:10 PM

Title: 4.10 LSD medium case v.s. small, drive shat?
Post by: mtle30 on February 17, 2012, 03:22:10 PM
I recently purchased a 4.10 LSD medium case, also got a drive shaft off a parts car (325) which I know is about 2 inches smaller, I figured this would compensate for the extra length on the diff, however it's not the case, the driveshaft doesn't line up with the center support to the car, soo.. I've seen others to slightly adjust the stock driveshaft, my question is how? And will it be enough to put the medium case differential in?
Title: 4.10 LSD medium case v.s. small, drive shat?
Post by: DesktopDave on February 17, 2012, 05:51:46 PM
There's a pretty large hex shaped sheet metal flange (or bell?) in the  middle of the driveshaft above the heat shield & exhaust pipe.    It'll be rusted together a bit, but with some PB Blaster and back-breaking effort you can loosen it  with large pliers.  I used a big set of channel lock slip-joint pliers (and threw out my shoulder).   The two parts of the shaft are splined pretty tightly, but are only  secured with an internal rubber compression sleeve.  I didn't need to shorten the shaft very much, the diffs are nearly identical other than the medium case being a bit fatter.

Be sure you clean out the hex bolts on the half shafts  really well, they're easy to strip out.  I found the easiest way to  re-mount it was to jack it up and get the driveshaft flange studs  threaded first, then the four large upper subframe bolts, then the half  shafts, then finally that rear "ear" mount.  I also had to bend the rear  mount a bit to get it lined up.
Title: 4.10 LSD medium case v.s. small, drive shat?
Post by: mtle30 on February 19, 2012, 09:53:11 AM
Thanks!! Given I'll be using he stock d/s I'll need to change the center support as well but I'll give it a shot and I'll post back if it works with some photos.
Title: 4.10 LSD medium case v.s. small, drive shat?
Post by: n2motorsports on February 20, 2012, 04:47:56 PM
keep a BFH hanging around too!  i smacked the rust off my diff when it wouldn't cooperate.