HP Dana 30 Gear Pattern Check
- Thread starter CupOfJoe190
- Start date
Yeah; looking at it this morning with fresh eyes I agree; that raises a question though - if I pull ~.0050 out of the pinion depth to run a new pattern; I'm gonna need to shim the carrier towards the pass. side more..... I only have the ARB and Dana 44 master shims on that side. How do I tackle that? Is it acceptable to chuck the Dana 44 master shim in a lathe and shave ~.0100" off so I can shift the carrier right?
Or; can I swap sides on the master shims? there is a .019" thickness difference between the two, and... incidentally, I was 99% sure I pulled the thicker one off the driver side, but when I went to do my first test fit using it there resulted in 0 backlash; so I flipped them around to shift the carrier. With these thick master shims and the ARB shims I've only got ~.0100" in other shims in the carrier for a pretty tight preload.
You are slightly deep...maybe in the 3 thou range. You are correct, you will need to swap shims from side to side and determine new shim placement for the smaller stuff.
Thanks! I turned .015" off the right side shim and it made a world of difference in fitting the housing and the preload feels much more manageable now.
I pulled ~.0020" out (I've got a pretty limited supply of pinion depth shims before I have to start sanding and making my own)
This looks pretty good to me;
Ok; interestingly when I pulled the pinion shim stack out, it measured almost no change from when I adjusted... maybe I mis-measured.
Pulled .003" and ran a new pattern; backlash is getting tight at .006; I dont know why but the drive side almost looks worse; I suspect that might be a result of the size of the contact patch having gotten larger; and me failing to have enough pressure on while running it.
That is definitely deep.
When you measure shim stacks, measure each shim separately, don't measure the stack as a whole.
When you measure shim stacks, measure each shim separately, don't measure the stack as a whole.
Thats what i've been doing; but also measuring the stack when I pull the setup race out to see if it matches; with that being said; I think the last adjustment was a step in the right direction.
Pinion depth is .0425"; backlash is a bit high at ~.0012
Only problem is my backlash was a bit wide on this on; right under .0012"; is it safe to assume tightening that up with a .0050" shim shift at the carrier shouldnt ruin this pattern?
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As I anxiously await a verdict on my latest pattern; I grabbed a clearer picture of the housing while its on the bench; the "ghost" pattern on the drive side looks pretty good to my untrained eye; just barely not touching the face with a wide square contact pattern; am I there or still just a touch deep?
Suspecting that I was still a bit deep; and not loving the wide backlash; I pulled another .0020" out of the pinion depth (pinion depth is .0410). Backlash on this fell right between .0090 and .0010 in 3 places; and I have to say this might be the best pattern I've run today.
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Ok; one more pattern; another .0030" less; this time at .0380" pinion shim stack. Backlash is dancing between .0010 and .0011; if this pattern is the winner, is it ok to run at the wide end of backlash like that? Getting it dialed down is going to require more machining of the master shim as I'm back to just the ARB and Dana 44 master shims on the right side.
Between this pattern at .0380" pinion depth and the last at .0410" pinion depth; I think the coast looks good here; but the drive looked a bit better at .0410; but I have proven in this thread that I'm garbage at picking a good pattern....
Between this pattern at .0380" pinion depth and the last at .0410" pinion depth; I think the coast looks good here; but the drive looked a bit better at .0410; but I have proven in this thread that I'm garbage at picking a good pattern....
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Joe, these are tough. I’m pretty new to gears, but the (what seems to me) abnormally large contact area makes them hard for me to read. Never-the-less, its fun to follow these along with guys like @hosejockey61 and @Blackjack helping us all out. I have at least 4 axles I want to regear in the next few months so good stuff!
Yeah; I'm far from even barely competent, but figure the more content and examples out there the better for the next guy. I run a pattern.. read like 24 posts of someone elses attempts, and then use that to try to self-direct while I wait for an expert; like Mike (HUGE THANKS TO YOU) to tell me I'm wrong.
You're not wrong, you're just on the correct path to get it right which is always a process.
I do think getting the backlash tighter helped with the drive side some; final pattern with a .0380 pinion depth and .0008 backlash:
Happy to report that I got everything buttoned back up; air lines ran and plumbed, and took the LJ out for a ~10 mile test run tonight with 0 issues. No gear noise whatsoever in either direction of travel, lockers engage and disengage without any issues; it all seems good to go. I'll do an oil change on both diff's in the next ~500 miles and past that, think i'm all set!
Thank you everyone for the help, and a major thanks to Mike for the special attention and guidance along the process.
Thank you everyone for the help, and a major thanks to Mike for the special attention and guidance along the process.
Figured it would be easiest to follow up in here: 500 mile oil change looked solid.
Took the LJ up to TN for Jeep invasion and a day out at Windrock; post Windrock I noticed some vibes and slight noise from somewhere; but the Jeep drove good home. Getting home I had a chance to take a look around; and I seem to have lost all of my preload on the rear pinion. The yoke is loose enough to move by hand a fraction of an inch. Pulled the cover and the gears and pinion look fine still; I’m assuming the best move right now is to pull the gears and redo the pinion preload; while inspecting everything? The only thing I can think of is that I might have spun a pinion preload shim, causing it to wear down to nothing? The pinion nut is still torqued to 200 ft. Lbs
Took the LJ up to TN for Jeep invasion and a day out at Windrock; post Windrock I noticed some vibes and slight noise from somewhere; but the Jeep drove good home. Getting home I had a chance to take a look around; and I seem to have lost all of my preload on the rear pinion. The yoke is loose enough to move by hand a fraction of an inch. Pulled the cover and the gears and pinion look fine still; I’m assuming the best move right now is to pull the gears and redo the pinion preload; while inspecting everything? The only thing I can think of is that I might have spun a pinion preload shim, causing it to wear down to nothing? The pinion nut is still torqued to 200 ft. Lbs