well i guess ill update. i bought diffs, got them all in and everything shimmed. couldnt get either of my motors running, then bought a 1:1 pickup, got a girl and a job and didnt have time for the hobby. so my savage sits in my basement, in a box, wrapped up with everything that goes with it. maybe one day ill sell it or try to get back into it.

did you install the CEN diffs?

nope. went with the high strength HPI diffs.

HPI 102692 is the way to go. My buddy put them in his XL after blowing several sets of the "heavy duty machined" HPI 86922, and he hasn't had a problem since. The cen diffs (which is what I have had in my savage for years) are a bit more work to install, whereas the 102692 is a simple bolt in. And as far as the diff itself, the cen unit will add rotating mass to the drivetrain.:( I did some extra work on mine to reduce it's mass to less than that of the stock savage....but that's another story. You'll want to shim the diffs either way. The 102692 comes with the necessary shims. And yeah, generally you can shim them like setting mesh on anything else, just a little tick of play. When you shim, start with the ring gear side, and push the diff over to that side when you check for play. Once you have the mesh right, just add shims to the other side to fill in the gap if necessary. Careful not to pack them in tight, you want to leave a small amount of lateral diff-to-bulkhead play in there too.

good luck:smile:

Thanks, so the 102692 will bolt right on my stock X 4.6 diff cups?

Yup, the ring gears will bolt right on to any savage cup (excluding the e-savage).

Watch your pinion depth during your install though. I can't remember if my friend had to shim his pinions when he installed the 102692 sets in his XL, and it might not be an issue at all with the 102692 sets, but when I installed the Cen diffs in my savage, shims weren't enough. I had to make sleeves to get the pinions to center correctly on the ring gears. Of course more pinion depth will give you a tighter mesh, so if you do have to shim them, you don't want to over-do it. Also (if you do wind up shimming the pinions) you need to make sure not to shim them so far in that they touch the diff cups.

Like I said, I can't remember what my friend did, at the time I was installing a new motor in my own truck, so I was only glancing over every once in a while, to call him names and to occasionally throw tools at him. The guy tears his truck down completely and rebuilds it in about 45 minutes, so I wouldn't be surprised if he didn't shim anything.:eek:

Thanks for the good info Helibrian :nod: