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Gears. How hard to DIY swap

  • Thread starter Thread starter 5.0StangRacer
  • Start date Start date Jun 30, 2005

5.0StangRacer

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Sep 16, 2003
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Damascus, Maryland
Jun 30, 2005
#1
  • Jun 30, 2005
  • #1
I'm not the best mechanic out there but I want 3.55's or so for my '66 and I was wondering how difficult it was to do it yourself? I'm not really intrested in paying to have it done unless thats the best way to go. Any advice from people who have done this? Also I have a 8.8 rear from a '96 explorer with 3.73's, trac-loc, disc brakes, the works, how difficult is that to swap for my stock 8 inch unit? anyone ever done it? Thanks
 

6Stang7

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Jun 1, 2003
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Jun 30, 2005
#2
  • Jun 30, 2005
  • #2
having a professional do it is the best way to go. if have have a dial indicator, and know what to look for on tooth contact, it's farily simple. however, if you dont have the right tools and know what you're looking for, i wouldnt do it. your is going to be harder them mine/most people on the forum that have done it because you have a 8.8. the 8" and 9" have a removeable carrier, the 8.8 doesnt.
 

5.0StangRacer

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Jun 30, 2005
#3
  • Jun 30, 2005
  • #3
i was talking about putting the gears in my stock 8" in my stang. its a 66 w/ 289, it has a 8" rear right?
 

skywalker

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Jun 30, 2005
#4
  • Jun 30, 2005
  • #4
5.0StangRacer said:
i was talking about putting the gears in my stock 8" in my stang. its a 66 w/ 289, it has a 8" rear right?
Click to expand...

Most likely it does, but you ought to look under there and find out.

I would say to do this: buy a center section off e-bay with the ratio and differential you want. You can usually get them for $400-500 with a buy it now.

I say this because if you do that you'll probably get a traction lock differential and a gear set in the ratio you want for the price of new gears and labor for install. Installation could then be accomplished fairly easily in your drive-way.
 

rbohm

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Apr 12, 2002
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tucson,az
Jul 1, 2005
#5
  • Jul 1, 2005
  • #5
best you have a pro install the gears in the pumpkin. the first thing you have to set in the pinion depth, the pinion bearing preload, the backlash, the carrier bearing preload, and finally check the contact patterns on the gear teeth. at each step you will be pulling everything apart and putting it back together untill you get the settings right. it may take you, if you have all the right tools, about 8 hrs to do, where as a pro may take only two hours. you can bolt the ring gear to the differential if you like as that will save about 5 min.
 
1

10secgoal

Active Member
Dec 1, 2003
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San Diego
Jul 1, 2005
#6
  • Jul 1, 2005
  • #6
rbohm said:
best you have a pro install the gears in the pumpkin. the first thing you have to set in the pinion depth, the pinion bearing preload, the backlash, the carrier bearing preload, and finally check the contact patterns on the gear teeth. at each step you will be pulling everything apart and putting it back together untill you get the settings right. it may take you, if you have all the right tools, about 8 hrs to do, where as a pro may take only two hours. you can bolt the ring gear to the differential if you like as that will save about 5 min.
Click to expand...

Exactly. Or you can measure the rear from flange to flange on the 8.8 compard to the 8in you have now. Then cut everything off and put it in. Would probably be cheaper than the gear swap, not to mention a stronger rear end.
 
C

chemeng

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Feb 21, 2004
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Louisville, KY
Jul 1, 2005
#7
  • Jul 1, 2005
  • #7
I got a 8" 3rd member last year on Ebay for $500. It has a trac-lock and 3.55 gears. No way I could have rebuilt my old one for that.
 

skywalker

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Jul 1, 2005
#8
  • Jul 1, 2005
  • #8
chemeng said:
I got a 8" 3rd member last year on Ebay for $500. It has a trac-lock and 3.55 gears. No way I could have rebuilt my old one for that.
Click to expand...

I just got a 9" trac-lok 4.11 off e-bay for $400. Beat that!

Seriously, $200 for gears, $400 give or take for the diff, plus labor whatever it may be? Just can't beat e-bay.
 

Hack

15 Year Member
Mar 23, 2004
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Minneapolis
Jul 2, 2005
#9
  • Jul 2, 2005
  • #9
chemeng said:
I got a 8" 3rd member last year on Ebay for $500. It has a trac-lock and 3.55 gears. No way I could have rebuilt my old one for that.
Click to expand...
Rebuild kits cost less than $100. There's something I don't understand here.
 
C

chemeng

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Louisville, KY
Jul 2, 2005
#10
  • Jul 2, 2005
  • #10
It's the trak-lok that kills you, they cost around $400.00. The rebuild only includes gaskets, shims, bearings, etc. He also wanted to go to 3.55 gears, that is another couple hundred.
Gets pricey quick.
 
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