locker install, gear pattern walking around.

[redtail]

Replacing the stock open carrier with a locker.

Old setup had a fairly consistent .014 backlash. When I installed the locker I set the backlash at .010 and checked it at several places, I had the backlash wander around from .006-.014. and sometimes more. There was a few spots of rust on three of the teeth (grouped together on the ring gear, so I could tell where they were. however that does not explain the other areas being out of whack.

I noticed it looked like the locker had been dropped on its edge at one point, and had some scarring that I had to file down.

I also noticed that the gear pattern was nutty as *ell, it seems to walk from the heel towards the toe. starts in the middle with a good pattern, center toe/heel center root/tip, coast and drive side, then the pattern walks from the center toe/heel all the way almost off the gear, to the toe side. then after a few teeth it just pops up into the center again and works its way back to the toe.

any ideas?

 

[Amac70]

Id start by diasembling everything again cleaning and starting over. File the ring gear and locker flat. retorque in proper pattern. Reset backlash and see if it improved.

 

[Timmy390]

Almost sounds like the ring gear isn't seated on the locker. Check both for warpage.

Tim

 

[Broncobowsher]

I go for take apart and check the mating surfaces. Sounds like there is a burr between the 2 mating surfaces.

If that doesn't fix it, install the locker without the ring gear and put the dial indicator on the ring gear mating surface and check for run out. I have never seen one with runout before, but it could be possible.

 

[xcntrk]

That's not going to do... Backlash tolerance needs to be within .002 around the gear.

Maybe try flipping the ring gear 90 degrees and reinstall. See if that changes anything.

 

[redtail]

Checked the run out on the locker it checked out fine, about .001 runout. Backlash continues to vary and it is between .007 and .012.

I did notice that the ring gear is not tight to the locker on the inner ring (not the gear mounting surface) so I can simply drop the ring gear on and it will spin freely when you just set the ring gear on the locker. the old open carrier did not do this, it had a tight fitment.

checked the mounting surface and it is glassy smooth on both sides (no crap, and the runout on the locker is in spec. orig ford 4.10 gears. All this stuff is used btw.

I tried my best to center the ring gear on the locker, but it still biases to one side or the other of the locker itself.

 

[Broncobowsher]

I did notice that the ring gear is not tight to the locker on the inner ring (not the gear mounting surface) so I can simply drop the ring gear on and it will spin freely when you just set the ring gear on the locker. the old open carrier did not do this, it had a tight fitment.

This has me thinking. Since the gears are at a bevel, any play radially will show up as backlash opening and closing up.

I remember a trick years ago about some flange nut wheels that would not center up. Use a couple of taper seat lugnuts to center the wheel, install the flange nuts, take off the taper seat and install the remaining nuts. I just don't know how well this would work long term? May work to confirm that it is the problem. Then it is off to measuring some stuff and finding the specs for the 9" and figure what is out. It may be the locker is over machined and under spec.

 

[Timmy390]

orig ford 4.10 gears. All this stuff is used btw

I hate to suggest this as I hate spending money just as much as the next guy but gears are cheap. I picked up a set of off brand 4.11's off ebay for $112 plus shipping. If the gear isn't fitting the locker correctly it's either the gear or the locker. Might as well start with the cheaper of the too. If it turns out not to be the gears, you can resale them and get most of you're money back.

Tim

 

[asinor]

I hate to suggest this as I hate spending money just as much as the next guy but gears are cheap. I picked up a set of off brand 4.11's off ebay for $112 plus shipping. If the gear isn't fitting the locker correctly it's either the gear or the locker. Might as well start with the cheaper of the too. If it turns out not to be the gears, you can resale them and get most of you're money back.

Tim

I'm going agree with this and with broncobowsher.

Sounds like the ring is off-center on the carrier and I don't know if there is a reliable way to get it to remain centered once you get it torqued down in the right place. Check that the bolts have the proper shoulder diameter for the holes in the carrier as this will control the centering if the ring and carrier are not hub centric. Next step would be test fitting a different ring gear from a different manufacturer in the same ratio.

 

[redtail]

they are not shouldered bolts, that's for sure.

the locker has the smaller diameter, the stock carrier fit like a glove.

I thought about the same thing, as soon as any type of shock load hits the ring gear it is going to shift to one side or the other and mess up the pattern and backlash even if I do get it centered.

I'll throw the open center back on and see if that is the issue.

 

[xcntrk]

Maybe you can try to determine if it's the locker or the ring gear that's off. That way you know which one you need to replace.

Throw the carrier in there without the ring gear installed. Get all the shims in place and make sure you seat the carrier bearings all the way down into the cups. Get the bearing caps on semi-tight to ensure it's all snug. Then throw a dial-indicator on the carrier side of the housing. Use the little needle plunger against the back of the carrier face and determine if it rolls out true with little to no variance. Do the same from the non-ring gear side with the plunger flush against the ring gear mounting surface. That should tell you if it's the carrier or the gear.

 

[redtail]

Maybe you can try to determine if it's the locker or the ring gear that's off. That way you know which one you need to replace.

Throw the carrier in there without the ring gear installed. Get all the shims in place and make sure you seat the carrier bearings all the way down into the cups. Get the bearing caps on semi-tight to ensure it's all snug. Then throw a dial-indicator on the carrier side of the housing. Use the little needle plunger against the back of the carrier face and determine if it rolls out true with little to no variance. Do the same from the non-ring gear side with the plunger flush against the ring gear mounting surface. That should tell you if it's the carrier or the gear.

Yup, i did that, run out was .001 or a hair more.

 

[xcntrk]

So it's definitely the ring then?

You mentioned it was OE? Maybe it got warped at some point throughout it's long life span...

 

[redtail]

might have been. Though with the old carrier it seemed to have consistent backlash and a good pattern.