8.8 pinion depth problem help trying to set right now

[Wa11banger]

i have read all the tech guides and am actually using a few of them to put the rear end back together. But I am having a real hard time with pinion depth..

Unable to use original shim set up for gauging because rear end was destroyed so starting from scratch

trying to achieve the 4.420 factory ford pinion depth and unable to do so. Without any shims deepest it can go riding directly on bearing is 4.347.

I have check and ensured bearing race is fully seated.. I have ground out all the old bearings so I can facilitate faster setup and checks but cannot for the life of me get any closer to 4.420.

Is the 4.420 just a guide? If you cannot achieve it what next? Is there a possibility new bearing race is thicker than old one?

any help would be appreciated again thanks

 

[doorgunner]

i have read all the tech guides and am actually using a few of them to put the rear end back together. But I am having a real hard time with pinion depth..

Unable to use original shim set up for gauging because rear end was destroyed so starting from scratch

trying to achieve the 4.420 factory ford pinion depth and unable to do so. Without any shims deepest it can go riding directly on bearing is 4.347.I may be wrong but it seems that you need a .073" stack of shims to get the suggested starting point. Then you can add/remove shims if necessary to get the proper backlash/clearance between the pinion teeth and the ring-gear teeth.

I have check and ensured bearing race is fully seated.. I have ground out all the old bearings so I can facilitate faster setup and checks but cannot for the life of me get any closer to 4.420.

Is the 4.420 just a guide? If you cannot achieve it what next? Is there a possibility new bearing race is thicker than old one?

any help would be appreciated again thanks

.

 

[kimcrwbr1]

Your probably gonna need a set of shims for the carrier bearings anyway to get the proper preload and gearlash without using the crush washer get the proper preload on the pinion and then set the gear lash and check runout on the ring gear a casing spreader makes shimming the carrier for proper preload on the carrier bearings and gearlash correct then use the gear paste and check the wear pattern on the gears then adjust the pinion depth accordingly. From my understanding you want to start using the original pinion shim or shim thickness if damaged taking it apart.

 

[Wa11banger]

AHA! success.. It is amazing how many things are very closely matched in terminology..
4.420 is the measurment from the base of the pinion to the center of axle.

Believe it or not its almost 4.420 from top of pinion to flat edge of entire housing.. Which is where my error comes in.

Finally pulled my head out and measured the bearing cap diameter. Found out is within
.0002 of being perfectly split in half. so I measured the thickness of my pinion. then installed it temporarily with the proper drag in lbs set. Then put a flat across bearing race faces and measured down to top of pinion. I came .034 short.. Ready for my total amazement? ford says .030 is the factory shim size for starting point and each ford pinion usually comes with a grease pencil number on the shaft.. Mine was 4.. Which means that .034 was the recommended shim needed and happened to be exactly what all my math said I needed

Now trying to figure out proper preload on the carrier.. Seems to be quite objective from what I am hearing from mulitple sources.

 

[kimcrwbr1]

Did you check the ring gear for run out? after you get the preload figured out on the carrier ideally you want .002" runout max