Diff Ring Gear Binding?
10-26-2017, 12:50 AM
#1
Diff Ring Gear Binding?
Gday all,
I'm building up a Drexler diff, and I've run into an odd one.
The vlsd that came out, backlash measured up at 0.005".
Same ring and pinion were used. Pinion wasn't touched.
Everything was cleaned and cleaned again, bearing seats, ring gear face, etc.
I had an issue with shimming at first, till I realised there were some bolts loose on the diff core itself. In that time I had already marked 3 or 4 teeth for pattern checking. Using an ink pen.
Fixed the diff core issue, continued on
The same shims went back in with the Drexler unit, backlash came to 0.0044". Happy with that, ever so slightly tighter, but nicely in range.
Now this is the odd part. The diff spins nicely, until I hit those 3 or 4 teeth that I marked previously on the ring gear. When they meet the pinion, it binds. You can still get it to turn, but it's noticeably harder. Once those teeth pass, it's back to free movement.
I see no eccentricity markings on the ring gear, even so there is no even ratio between the ring and pinion.
I see no burrs, or anything that would catch.
It seems to sudden for runout issues.
Am I feeling just the teeth binding a tad as the diff is a bit tighter than before? That's my thought, but I'm concerned to actually run the diff and have those tight teeth knacker the bearings or have it **** the bed totally.
I'm a bit staggered at the coincidence that it's the same teeth I marked previously, surely leaving some pen ink on can't have done some weird voodoo metallurgy stuff...
Any thoughts are greatly appreciated, cheers
I'm building up a Drexler diff, and I've run into an odd one.
The vlsd that came out, backlash measured up at 0.005".
Same ring and pinion were used. Pinion wasn't touched.
Everything was cleaned and cleaned again, bearing seats, ring gear face, etc.
I had an issue with shimming at first, till I realised there were some bolts loose on the diff core itself. In that time I had already marked 3 or 4 teeth for pattern checking. Using an ink pen.
Fixed the diff core issue, continued on
The same shims went back in with the Drexler unit, backlash came to 0.0044". Happy with that, ever so slightly tighter, but nicely in range.
Now this is the odd part. The diff spins nicely, until I hit those 3 or 4 teeth that I marked previously on the ring gear. When they meet the pinion, it binds. You can still get it to turn, but it's noticeably harder. Once those teeth pass, it's back to free movement.
I see no eccentricity markings on the ring gear, even so there is no even ratio between the ring and pinion.
I see no burrs, or anything that would catch.
It seems to sudden for runout issues.
Am I feeling just the teeth binding a tad as the diff is a bit tighter than before? That's my thought, but I'm concerned to actually run the diff and have those tight teeth knacker the bearings or have it **** the bed totally.
I'm a bit staggered at the coincidence that it's the same teeth I marked previously, surely leaving some pen ink on can't have done some weird voodoo metallurgy stuff...
Any thoughts are greatly appreciated, cheers
10-26-2017, 07:30 PM
#3
It's gunna have a Z1 extra capacity diff cover, and the cooling fins, so that should help with temps somewhat too.
I'm gunna have a look now, clean the teeth up, lube everything up, and remeasure the backlash everywhere. Then I'll pattern check everywhere and see if it's something odd like a imperfection it's now catching on.
10-28-2017, 03:48 PM
#4
I gave a little bit of a scrub to the few teeth that were binding, a good clean and a relube, and actually it eased up a bit which surprised me, it then started to pick up either side a little bit. Backlash on the tight spot was fairly minimal, 2 thou-ish
Needless to say I'm stripping it out again, and reclean and lube it, make sure everything is immaculate. Try again, then if no good, start reshimming
Needless to say I'm stripping it out again, and reclean and lube it, make sure everything is immaculate. Try again, then if no good, start reshimming
10-29-2017, 03:07 PM
#5
Does anyone have any diff bearing shims laying around that I could nab?
The dealer here wants heaps for shims and wouldn't let me do a swap or even get a test fit done.
Using the old shims with the Drexler, I think it was a bit too tight as pulling the unit out took a heck of a lot. What I need to do is test out and get a set of shims that will slot in a bit easier, and then from that point work on the preload, backlash and pattern.
So if anyone has any shims they'd be happy for me to test fit with, that would be awesome. Needing a helping hand here as spending 200 bucks on shims to only use 2 is a bit crazy
The dealer here wants heaps for shims and wouldn't let me do a swap or even get a test fit done.
Using the old shims with the Drexler, I think it was a bit too tight as pulling the unit out took a heck of a lot. What I need to do is test out and get a set of shims that will slot in a bit easier, and then from that point work on the preload, backlash and pattern.
So if anyone has any shims they'd be happy for me to test fit with, that would be awesome. Needing a helping hand here as spending 200 bucks on shims to only use 2 is a bit crazy
10-29-2017, 04:22 PM
#6
You are better off finding a specialty shop that can get you shims that will work. Remember when you add thickness on one side you need to take away from the other, unless you are trying to loosen the carrier bearing preload.
For carrier preload, here is what the FSM recommends (from an 03 fsm):
Measure the turning torque of the carrier at the ring gear retaining bolts with a spring gauge, J-8129. Specification: 34.2 - 39.2 N (3.5 - 4 kg, 7.7 - 8.8 lb) of pulling force at the ring gear bolt.
For carrier preload, here is what the FSM recommends (from an 03 fsm):
Measure the turning torque of the carrier at the ring gear retaining bolts with a spring gauge, J-8129. Specification: 34.2 - 39.2 N (3.5 - 4 kg, 7.7 - 8.8 lb) of pulling force at the ring gear bolt.
10-29-2017, 04:28 PM
#7
You are better off finding a specialty shop that can get you shims that will work. Remember when you add thickness on one side you need to take away from the other, unless you are trying to loosen the carrier bearing preload.
For carrier preload, here is what the FSM recommends (from an 03 fsm):
Measure the turning torque of the carrier at the ring gear retaining bolts with a spring gauge, J-8129. Specification: 34.2 - 39.2 N (3.5 - 4 kg, 7.7 - 8.8 lb) of pulling force at the ring gear bolt.
For carrier preload, here is what the FSM recommends (from an 03 fsm):
Measure the turning torque of the carrier at the ring gear retaining bolts with a spring gauge, J-8129. Specification: 34.2 - 39.2 N (3.5 - 4 kg, 7.7 - 8.8 lb) of pulling force at the ring gear bolt.
Yeah, I'm first looking to reduce the preload, then go about the rest of the process.
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11-07-2017, 04:06 PM
#8
So you have 44thou backlash throughout most of the ring gear and a few teeth are 2thou?
This excessive runout can be caused by: Ring gear damage, or the drexler housing is out of round. Take off the ring gear and measure the drexler diff for runout and go from there.
This excessive runout can be caused by: Ring gear damage, or the drexler housing is out of round. Take off the ring gear and measure the drexler diff for runout and go from there.
11-08-2017, 03:37 PM
#9
New Member
no no it's .0044", 6 tenths tighter, not 44thou
11-22-2017, 12:18 AM
#10
^Yes, it's 0.0044" backlash, which then binds suddenly for 2 or 3 teeth on the ring gear, and then goes back to the same backlash
Finally got a chance to do some more to the diff, had it out, inspected and cleaned it all up, made sure the teeth and housing were pristine, with a light oil coat, and reinstalled it, same shims. No change in feel though, it still binds.
As a curiosity, I hooked a big drill up to the diff so I could just spin it at a constant rate and see if anything changed. As the speed came up you could definitely feel it pulsing. Whether the engine and drive train would easily mask thst, that's another matter.
I cleaned the oil off the binding section and there was way more friction.
Tomorrow I will do the lash, and preload check.
This leaves me wondering what to do though. I'd seen one post where a guy appeared to have the same issue, and couldn't figure it out. He then installed it and ran a few tanks of gas through and it came right, like it just needed to rebed the teeth in a bit.
Another source said any binding is a nono, and to fix it.
In that case, I'm probably at the point where I'll consider sending it to a specialist to rip apart and figure it out.
Incredibly frustrating
Finally got a chance to do some more to the diff, had it out, inspected and cleaned it all up, made sure the teeth and housing were pristine, with a light oil coat, and reinstalled it, same shims. No change in feel though, it still binds.
As a curiosity, I hooked a big drill up to the diff so I could just spin it at a constant rate and see if anything changed. As the speed came up you could definitely feel it pulsing. Whether the engine and drive train would easily mask thst, that's another matter.
I cleaned the oil off the binding section and there was way more friction.
Tomorrow I will do the lash, and preload check.
This leaves me wondering what to do though. I'd seen one post where a guy appeared to have the same issue, and couldn't figure it out. He then installed it and ran a few tanks of gas through and it came right, like it just needed to rebed the teeth in a bit.
Another source said any binding is a nono, and to fix it.
In that case, I'm probably at the point where I'll consider sending it to a specialist to rip apart and figure it out.
Incredibly frustrating
Last edited by MB037; 11-22-2017 at 12:20 AM.
11-22-2017, 05:02 AM
#11
New Member
^Yes, it's 0.0044" backlash, which then binds suddenly for 2 or 3 teeth on the ring gear, and then goes back to the same backlash
Finally got a chance to do some more to the diff, had it out, inspected and cleaned it all up, made sure the teeth and housing were pristine, with a light oil coat, and reinstalled it, same shims. No change in feel though, it still binds.
As a curiosity, I hooked a big drill up to the diff so I could just spin it at a constant rate and see if anything changed. As the speed came up you could definitely feel it pulsing. Whether the engine and drive train would easily mask thst, that's another matter.
I cleaned the oil off the binding section and there was way more friction.
Tomorrow I will do the lash, and preload check.
This leaves me wondering what to do though. I'd seen one post where a guy appeared to have the same issue, and couldn't figure it out. He then installed it and ran a few tanks of gas through and it came right, like it just needed to rebed the teeth in a bit.
Another source said any binding is a nono, and to fix it.
In that case, I'm probably at the point where I'll consider sending it to a specialist to rip apart and figure it out.
Incredibly frustrating
Finally got a chance to do some more to the diff, had it out, inspected and cleaned it all up, made sure the teeth and housing were pristine, with a light oil coat, and reinstalled it, same shims. No change in feel though, it still binds.
As a curiosity, I hooked a big drill up to the diff so I could just spin it at a constant rate and see if anything changed. As the speed came up you could definitely feel it pulsing. Whether the engine and drive train would easily mask thst, that's another matter.
I cleaned the oil off the binding section and there was way more friction.
Tomorrow I will do the lash, and preload check.
This leaves me wondering what to do though. I'd seen one post where a guy appeared to have the same issue, and couldn't figure it out. He then installed it and ran a few tanks of gas through and it came right, like it just needed to rebed the teeth in a bit.
Another source said any binding is a nono, and to fix it.
In that case, I'm probably at the point where I'll consider sending it to a specialist to rip apart and figure it out.
Incredibly frustrating
Have you contacted the manufacturer? They should be able to tell you what you should expect.
As a former machinist/assembly tech, metal is not forgiving... You know this. It's either perfect or it will destroy itself or a bearing...
11-25-2017, 07:54 PM
#12
I will probably end up sending it to a specialist at this stage, and see what they can make of it. Good thing I bought a second diff so the car stays driveable.