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Old 08-05-2008, 07:33 AM
Goldduster360 Goldduster360 is offline
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Originally Posted by Mike H
The other thing you learn after you have done 50+ installs is what it takes to make a change in the look of the pattern I set them up with the pinion depth on the new pinion but before I take out the original I check the PD that way I can figure the shim I need to start with.( I have the T&D pinion depth tool and it was worth the $ I paid for it the first time I used it. The $99.00 ones are junk don't waste your money) Also if the pattern looks bad from the get go I make a big jump .012-.018 or so in the pinion shim (you would not putt the entire hole when golfing). The first pictures looked to me like you had to much shim (or on a 8-9" ford not enough) Tooth up on edge and toward the root of the ring gear. I bet it made noise when you were turning it to check the mesh of the teeth. I would run what you have but take it easy on it for 40-50 miles, drive it 2-3 miles then let it cool off a few times before getting out on the freeway. If you want to break it in then pull the cover again and run another test pattern it will look better.

Feal good in the fact that you did not have to take it to someone else to do it. Mike
Thank you again Mike, your insights have been greatly appreciated both by me and certainly by anyone else surfing this thread looking for answers.

And yes, the gears were noisy when turning them over by hand when the depth setting was too deep, I thought it was just my imagination, it almost sounded like a wood pecker pecking away in the distance when they were turned, thanx again, that is a good piece of information. I have set up quite a few straight cut gears on my radio controlled models by sound and feel, too notchy, you know it's meshed tight, high pitched whine usually a little loose.

Also, my stock gearset was at -0, could still read it on the pinion face but yet there was an .072" thick shim under the pinion bearing inner race. Based on my original math I had added like .038" of shims based on the suggested pinion depth on the new set(was not aware of inner race shim yet either). Was not even close. Also, not sure why that spacer was under the bearing cup, but it had to come out as I was still about .004" too deep with it in because with no shims on the pinion stem it was still too deep. I am sure there was a reason for it to be there originally but as a newbie to this it is just another piece of the puzzle I had to put together on my own. I did not see anything on my instruction sheet about checking for shims behind bearing races. Imagine the frustration of taking all the shims from behind the set up bearing on the pinion and finding out that it was still sitting too deep(after about 5 attempts at set up). Out of frustration I hammered out the old race with a brass drift to install the new race and found this .072" thick shim.

One more question Mike while I have your attention:

I understand about setting the pinion bearing drag at 22-25 inch pounds for new bearings but what should you do for pre-load on the carrier bearings? Mine being a chrysler 8-1/4" it has threaded adjusters. Do you just snug them up to make sure there is no play before attaching the little anti-loosen brackets? I have been using an elbow screw driver and a rubber mallet to gently snug them up. It sounds crude but it's free and it works.

Last edited by Goldduster360; 08-05-2008 at 08:22 AM.
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