Rebuilding the 8.8, hit a snag

[slow84lx]

In the efforts to get my 1984 coupe back on the road I picked up a parts car 1995 GT, 5-speed early this year. Free time in the garage has been limited but I am finally getting around to parts rebuilding /swapping. The plan is to put the complete drivetrain from the SN95 into the '84 along with the brakes, spindles, & probably the front A-arms.

Swapped the 7.5 from the '84 into the '95 no problem. Took the 8.8 out of the '95 apart to rebuild prior to putting it in the '84. Purchased a Ratech rebuild kit, replaced all bearings / seals, rebuilt the Trak-loc, cleaned it all up and re-assembled w/ 3.73 gearset.

The problem:
Took the carrier over to a friends house and pressed the old bearings off and new bearings on. Bearings are pushed on all the way to the shoulder. I put the carrier back into the housing but can't get the shim stock back in on both sides. I measure the original shims carefully and put them back on the same side. One side will go right in but try as I might I could not the get the shim in on the side opposite the gear. Pry bar will not move the carrier over far enough to get the shim started. I broke the original shim on that side and replaced it with a shim stack of the same thickness from the Ratech kit.

So what's the trick to getting the shims installed on both sides of the carrier?

[Baba Ganoush]

Sounds like you need to shave a thousandth until the stack fits, then check backlash. You should be fine.

I'm no expert, though I have rebuilt quite a few 8.8 and it's a bonus when the stock shims slide back in and work, but it's not a certainty.

[slow84lx]

I did try taking a .010 shim out of the stack, no difference. I put the .010 back in the stack and took out a .095. Was trying to get the stack in and then wedge the .095 back in but no luck. Just got frustrated and walked away. I will go back to it this afternoon and try again.

[TX21]

Did all the measuring I could and got the backlash where I thought it needed to be and still have some noise coming from my unit as well. Stupid things are super frustrating.

[Baron Von Crowder]

Did you change the gearset?

[Broncojohnny]

You have to shim it to the correct backlash for the new gear set. It needs to be around .008 to .010". You also need the correct pinion depth or you need to check the wear pattern on the gears.

[Baba Ganoush]

Sorry my assumption was you were using the stock gearset. If you changed gear sets you need to "reset" all measurements and do just as ALP ^^ said. It takes experience and the right tools to dial in correct pinion depth and backlash.

I've had the best luck with used FMS gear sets, if they're aftermarket and NIB I need guidance and a little luck!

Edit: also your pinion bearing preload is VERY important if you changed it. This is the first step in ensuring correct assembly.

[Sleeper]

Ford racing has a good manual for setting up the 8.8. It's on the late model restoration site.

[JETFAST]

sounds like your pinion depth is off. especially if it's making noise.

[slow84lx]

sounds like your pinion depth is off. especially if it's making noise.

As much as I hate to admit it this was essentially the problem. Was getting good reading with an inch/lb torque wrench. Took it back apart and discovered the crush sleeve not squeezed down all the way. Ordered a new one + a shim kit, went to Sears and purchased a long 1/2 breaker bar, put a pipe on the end of that, and all is well. Checked & triple checked all adjustments and have a great pattern with the new 3.73's. I'm looking forward to laying some rubber down on the road in the near future.

Thanks for all of the help!