Gear pattern check

Jeepster78

Jeepster78

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Hello,

I’m regearing my Dana 30 to 4.88 and this is only the second time I’ve done gears.
I think my pinion is a bit shallow and wanted input. Do you think a .003 shim behind the pinion should be good or would you go thicker. And also it looks to be hitting the heel a bit and should I decrease the backlash a bit I’m at 10 thousandths in 3 spots and 7 in one. The manual says 10-15 thousandths on backlash for new gears but I’ve read and seen videos where they go 6-9 for backlash on new gears.
Another question I have koyo setup bearings and timkin for the final setup should that make a difference as well?

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I just did this. I’m interested to see what others think, but I think shallow.

I’d start with something bigger than .003 to confirm. Maybe .006 or more.

That will hopefully skew you deep and you can dial it in that way.

don’t use different brand setup vs to be installed.

Most here will tell you to set a Dana 30 up tight (meaning 6ish BL). What manual says 10-15?
 
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Jeepster78 said:
Hello,

I’m regearing my Dana 30 to 4.88 and this is only the second time I’ve done gears.
I think my pinion is a bit shallow and wanted input. Do you think a .003 shim behind the pinion should be good or would you go thicker. And also it looks to be hitting the heel a bit and should I decrease the backlash a bit I’m at 10 thousandths in 3 spots and 7 in one. The manual says 10-15 thousandths on backlash for new gears but I’ve read and seen videos where they go 6-9 for backlash on new gears.
Another question I have koyo setup bearings and timkin for the final setup should that make a difference as well?

View attachment 432530

View attachment 432531
Click to expand...

Definitely wait for someone like @hosejockey61 or someone with more experience.
my look at it says to decrease backlash and try to get away from the heel and toe. Backlash would be better around 7 to 8 thousandths. 10 is on the maximum for the spec if i remember correctly.
i would try to add a shim behind the pinion and see if it produces a better pattern. Looks like it could definitely go deeper. Looking at the contact patch its still footballed. Its eaiser to find to far in both directions and find the best pattern inbetween. Also adding pinion shims will help center the pattern.
 
Youkon setup says backlash 10-15.
I think I read somewhere where timken and koya are manufactured by the same company in Japan but not sure. Ok I’ll try 6thousanths and see what I get.
 
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Jeepster78 said:
Youkon setup says backlash 10-15.
I think I read somewhere where timken and koya are manufactured by the same company in Japan but not sure. Ok I’ll try 6thousanths and see what I get.
Click to expand...

i asked same question re: setup bearing being different few months back and was told to make sure they match brand. YMMV but it’s $40 or so to be sure it’s done right (with as few headaches as possible)
 
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I would throw .005 or so at the pinion first and see how that looks. Do not fixate on the pattern being at the heal or toe and just concentrate on its position from root to crown. If your shims allow you to get to .008 backlash without too much effort go for it but .010 is still passable.
 
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Ok added .006 behind the pinion race is here is the pattern. Looks pretty close to me but I need an experts opinion.
The backlash is at 8 thousandths in multiple spots and then at two spots I got a 10 thousandths and a 6 thousandths. Is this ok?

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If it was me, I’d put another .003 and confirm it actually goes deep. Keep these measurements handy in case you want to go back to it
 
Ok added .003 to the pinion and I think I like this one is a better pattern. Backlash is still at .008 in multiple spots and in two spots it’s .010 and .006.
Let me know if this is a good pattern to run or should I adjust some more?

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That last setup puts you right at the verge of being too deep but also remember that with a LP30 that you are driving off the coast side of the gear so running on the deep side is not necessarily a bad thing.
 
Blackjack said:
That last setup puts you right at the verge of being too deep but also remember that with a LP30 that you are driving off the coast side of the gear so running on the deep side is not necessarily a bad thing.
Click to expand...

Would you run that pattern or pull .001 or .002 from the pinion?
 
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