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Potential Dumb Diff Question

  • Thread starter Thread starter LarsD
  • Start date Start date Mar 11, 2015

LarsD

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Jul 2, 2002
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Mar 11, 2015
#1
  • Mar 11, 2015
  • #1
So the trac-lok in my 8.8 is shot. When I have it on stands I can rotate one of the rear wheels with the car in gear and see the opposite side rotating in the other direction. However at some point in the car's life someone put 3.55 gears in it (have verified with the cover off). I am happy with the gears, but not the worn out differential. Would I have to completely reset the gear lash if I just R&R the carrier without disturbing the pinion? I would like to put a Tru-trac in the car with a pair of Moser axles and a new aluminum diff cover while reusing the ring gear. Is this possible?
 

7991LXnSHO

wanna catch the space herp
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Kearney, NE
Mar 11, 2015
#2
  • Mar 11, 2015
  • #2
The easiest thing would be to put new clutches in the existing carrier. I am afraid you will have to check all the shims when the carrier is replaced. Although the Auburn gears sounds like a great idea with nothing to slip or wear and still silent operation, (I amdrawing a blank on True track) so it may be worth it.
 

LarsD

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#3
  • Mar 11, 2015
  • #3
Well I wanted to step up to 31 spline axles anyway since the car makes around 400ish hp, I figure if I manage to hook up on 28 splines I may trash the Ranger axles that are in the 8.8 right now.
 

hoopty5.0

mechanicus terribilis
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Mar 13, 2015
#4
  • Mar 13, 2015
  • #4
You could possibly get by without having to re-shim the pinion. You should absolutely check the wear pattern if you do install a new differential. More than likely will have to re-shim the new carrier.
 

Chuckman

GTFO you fat, heavy bastard
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Mar 13, 2015
#5
  • Mar 13, 2015
  • #5
when setting these up backlash is (mostly) controlled by the shims on the sides of the carrier. you'll need to check it (and set it) with the new carrier, but unless you're also swapping the whole housing, the pinion depth from the centerline of the carrier wont change, and you wont have to re-shim that.
 

7991LXnSHO

wanna catch the space herp
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Mar 14, 2015
#6
  • Mar 14, 2015
  • #6
Theoretically and if things go to plan. They rarely seem to go that easily when switching brands of parts, and if you are worried about breaking things, getting them set just right is important.
 

LarsD

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Mar 21, 2015
#7
  • Mar 21, 2015
  • #7
Yeah that is kind of what I was thinking. Might have to try and see how it works out.
 

Chuckman

GTFO you fat, heavy bastard
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#8
  • Mar 21, 2015
  • #8
just so you know, i swapped in a 31-spline ford t-lok/moser axles while keeping my same ring/pinion gears. had to take around .070" worth of shim out to get the carrier to even fit in compared to the stock 28 (the new 31-spline carrier is a completely different casting too, dunno if its always been like that), and after checking the backlash, it all had to be take out of the ring gear side (shims before were .264/.270, after were i think .206/.267). mesh pattern still looked fine though (controlled mostly by pinion shim). thats probably about what you'll have to look forward to.
 
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