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Old 08-04-2008, 04:32 PM
Mike H Mike H is offline
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Originally Posted by Goldduster360
There are a couple of good picks of the coast side under the title "Removed only .004" a couple postings up on this thread. The first pick shows both the drive and coast patterns. I thought the coast actually looked closer to "optimum" than the drive did. At this setting both the drive and coast looked as good as I could get them.

Thanx for your inputs Mike H., I was wondering why no matter what I did, good or bad none of my patterns looked like anybody's pictures or illustrations. The directions and pattern suggestions that came with the gears were not very helpful for a newbie on his first gear set up either. I also did the math and tried setting up the gears at the suggested pinion depth, results were poor. With lots of internet surfing I was able to deduce that no gear set up is going to be picture perfect and only trial and error based on several pattern readings is going to get it right.

I also suppose the lower priced sets are not going to have the factory type of lap job that would yield a more perfect first set up pattern. I can also assume that I should be pretty gentle with this set during it's first couple hundred miles as they will finish lapping themselves during break in.

I can't stress how important it is to anyone contemplating one of these jobs for the first time that they really don't know what they are in for until they get into it. That being said, anybody who can turn a wrench and read a dial indicator can probably set one of these up. It will require being very patient, looking at several examples on the internet of acceptable/unacceptable patterns to guide them in what corrections to make along the way and posting on this site for support when needed. Contacting the gear manufacturer with a picture of your pattern set up can be very helpful too, which is what I ended up doing.

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
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