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GEARS INSTALLATION HELP

  • Thread starter Thread starter rideapony
  • Start date Start date Jun 20, 2010

rideapony

Active Member
May 28, 2006
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SANTA ROSA, CA (North Bay Area)
Jun 20, 2010
#1
  • Jun 20, 2010
  • #1
Hi all,
This time I'm installing a set of 3.55 gears, to be precissed I'm transfferring them from my old rear end housing to a newer one which I already painted and ready to go. I've been reading a few installation instructions and just want your opinion. The newer rear end came out of a '95 GT all assembled with 2.73's, I read somewhere that to set the pinion depth for the new gears I can measure the old pinion gear head and shim (Set by the Ford factory), and then measure the new pinion head and make the shim adjustments to achieve the same thickness as the old pinion and shim.

Well like I said I had my new 3.55 gears already installed by a rear end shop, and I just took everything apart.
I measured the old pinion (Four different spots then averaged) and it measured 1.8885"+ 0.027" (shim)= 1.9155 Pinion depth.

Then I measured the new pinion (Four different spots then averaged) and it measured 1.8885" + 0.0235" (shim)= 1.912"

So both pinions measure exactly the same!!!!!! But Ford used a shim 0.0035" thicker than the rear end shop. I noticed sort of a faint whinning noise right after the installed and took it back to the shop but they said "Thats the way those gears sound". I noticed that the wear parttern on the ring gear teeth look a bit shallow (backlash was good) maybe that's why increassing the shim thickness might work better

One of the articles I read SSOTN - Gear Install
says that Ford uses the MHD (Master Housing Dimension) to set up their gears and should be more accurate, is that truth????

Should I use the same shim thickness from the old pinion? Or keep the one the rear end shop installed?

The reason I'm asking your opinion is because I want to be certain it will work correctly because I'm installing a new Detroit Truetrac and 31 spline Moser axles and don't want to mess it up!!!

Please give me your honest opinion on this matter.

PLEASE HELP!!! Thank you all a bunch!!!, Nick
 
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