Need help interpreting gear pattern

The billavista gear bible is correct in that you need to have zero lateral movement when seating the carrier/locker. You can add additional shims at final assembly for a higher preload. If you're comfortable with the preload then good. As far as pinion preload, don't worry about getting to spec just yet or 100 ft/lbs etc. Tighten the pinion nut until the bearing has resistance (not too much). It becomes a "feel" thing after you have set up several sets. The goal is to prevent lateral or in/out movement.

I was looking through all of your pictures from the previous post. I think your 53 "appears" to be the best depth. But the consistency of your pattern still bothers me. Look at each tooth and the pattern is slightly different...some have marking compound diagonal lines where others don't etc. Try more pressure on your ring gear when running the pattern. When I use a drill and a glove, I let the gear make 6 or 7 revolutions in each direction. The more pressure you apply, the better the pattern markings.
 
not sure what my cocked eye is seeing.
42 looks flat top and round bottom .........to shallow.
49 not horrible, just messy.
at 50 your flat in the bottom, 53 flat in the bottom, deep.
then 44 goes back the other way, flat top round bottom, shallow.
then we jump back to 54 and back into the bottom.

47 looks pretty dam close to me.........nobody else? not high not low not at either end of the tooth.
what am i missing here?
 
I contacted ECGS which is who I bought the gears and rebuild kit from. Their tech said heel to toe usually does not change and it Is more controlled by the actual gear and or housing then the depth or backlash. I sent the photos and they recommended running the pinion at 50.

I think the 53 pattern looks so bad because it was one of the first few I ran. I'm going to check for any lateral play with the carrier and maybe add a little bit of shimming on both sides even if it's just to verify the pattern isn't shifting. One thing I thought about was my inner pinion setup bearing. I made it myself and ground down the OD so it would be a slip fit into the housing. It was tough to get it right and it may be a tad loose, part of the reason I've been torquing the pinion to 100 ft lbs. Maybe it's shifting a bit under load? Although 100ftlbs is a lot of compressive force, I might try 200 next time.
 
mikalcarbine said:
I contacted ECGS which is who I bought the gears and rebuild kit from. Their tech said heel to toe usually does not change and it Is more controlled by the actual gear and or housing then the depth or backlash. I sent the photos and they recommended running the pinion at 50.

I think the 53 pattern looks so bad because it was one of the first few I ran. I'm going to check for any lateral play with the carrier and maybe add a little bit of shimming on both sides even if it's just to verify the pattern isn't shifting. One thing I thought about was my inner pinion setup bearing. I made it myself and ground down the OD so it would be a slip fit into the housing. It was tough to get it right and it may be a tad loose, part of the reason I've been torquing the pinion to 100 ft lbs. Maybe it's shifting a bit under load? Although 100ftlbs is a lot of compressive force, I might try 200 next time.
Click to expand...

Yeah the pattern is just a little tough to see well in the picture. 50 could be the magic number. As far as your pinion nut tightening, are you doing it with shims in place? The reason I ask is because your ft/lbs value doesn't need to be that high when running a pattern. If you have no shims in place, you run the risk of damaging the bearing. If you have too many shims in place, then the bearing can't seat properly. When I run a pattern, I don't add any pinion shims initially. I tighten the nut until I feel resistance on the bearing. After my pattern is good, then I'll figure out my shim pack that will give me the desired 16-20 in/lbs of preload with the nut at 180-200 ft/lbs. Once the shim pack is figured out, then I'll install the seal and the new nut. I use a "setup" nut all the way to final assembly. Since the pinion nuts are one time use and have sharp threads that grab onto the pinion threads, I take an old nut and dremel the sharp edges down just enough so they won't gall the pinion threads.
 
mikalcarbine said:
I tried a pinion depth of 45,46 and 47 but my main concern right now is trying to get the pattern centered between the heel and toe. With my pinion at 46 moving the backlash from 0.006 to 0.010 had no impact on the toe/heel contact. I even moved the pinion a few thousandths while maintaining backlash shimming with little change. Any thoughts?

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The drill idea was great. I wasn't sure if I was loading the carrier enough so I put in both axle shafts and my girlfriend helped me hold one while I loaded the carrier by resisting the other shaft while turning the pinion. The pattern didn't change so I know I'm loading everything good

I have plenty of other photos but didn't think posting was helpful. I can post a set of 6 vs 10 backlash if anyone is curious
Click to expand...
This one looks fine to me. This to 50 will likely be just fine.

You won't be able to adjust heel to toe. As long as you have full contact, which you do, it'll be good.
 
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hosejockey61 said:
Yeah the pattern is just a little tough to see well in the picture. 50 could be the magic number. As far as your pinion nut tightening, are you doing it with shims in place? The reason I ask is because your ft/lbs value doesn't need to be that high when running a pattern. If you have no shims in place, you run the risk of damaging the bearing. If you have too many shims in place, then the bearing can't seat properly. When I run a pattern, I don't add any pinion shims initially. I tighten the nut until I feel resistance on the bearing. After my pattern is good, then I'll figure out my shim pack that will give me the desired 16-20 in/lbs of preload with the nut at 180-200 ft/lbs. Once the shim pack is figured out, then I'll install the seal and the new nut. I use a "setup" nut all the way to final assembly. Since the pinion nuts are one time use and have sharp threads that grab onto the pinion threads, I take an old nut and dremel the sharp edges down just enough so they won't gall the pinion threads.
Click to expand...

Based on Bilavista's guide, I set up an approximate inner pinion shim. When torqued to 100ftlbs I was typically getting 10-30 in lbs of preload. As I said above this was to avoid any wiggling of my setup shim. I was also worried about my old pinion nut scoring up my new pinion threads but it was so worn it hasn't done any damage, probably explaining why my pinion bearings and shims were toast before this, I think the previous shop reused a nut and it backed off over time. For future reference, where do you typically dremel a stover nut to prevent it from galling threads?

pcoplin said:
This one looks fine to me. This to 50 will likely be just fine.

You won't be able to adjust heel to toe. As long as you have full contact, which you do, it'll be good.
Click to expand...

Thanks guys. Last night I gave it one last go at 50. I measured for any movement in the carrier and there was none but I still added 2 thou of shimming on each side to ensure it wasn't moving at all. It was definitely a lot tighter going in and coming out but didn't seem to add any preload when measured via the pinion. I also set the pinion to 200ft lbs just in case the inner pinion setup bearing was moving at all. The pinion preload on that was 25 in-lbs. I then ran a few patterns. Backlash was ~6-7. It seems like it did pull the pinion in a little, thoughts?

50-68-20-17-6.jpg


50-68-20-17-6-2.jpg
 
Went to start buttoning everything up and I realized there are two pinion preload specs floating around. The FSM says 20-40 in-lbs for new bearings and everywhere else seems to say 14-19 in-lbs. Thoughts?
 
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