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big case diff. pinion slop
Posted: Feb 20, 2013 9:43 AM
by Bill in MN
My big case has slop in its pinion but is otherwise just fine. It's a low mile unit, the seals/bearings are just fine and there's no reason to rebuild it.
Do I need to start from scratch and put a new crush unit in there or can it simply be tightened until the slop's out of it?
Posted: Feb 20, 2013 11:33 AM
by turbodan
Radial or axial?
Posted: Feb 20, 2013 12:16 PM
by Bill in MN
Axial. It's not much but enough to translate to a few inches when the wheels are rotated.
Posted: Feb 20, 2013 12:17 PM
by tsmall07
Is the ring or pinion gear wear pattern off? Can you post a picture of the teeth?
I'll say that just tightening the pinion nut is almost never the correct solution.
Posted: Feb 20, 2013 12:19 PM
by tsmall07
Bill in MN wrote:Axial. It's not much but enough to translate to a few inches when the wheels are rotated.
That sounds normal to me. There is a specific amount of lash built into a ring & pinion set up. If your pinion isn't sliding in and out of the front of the diff (pinion depth) or wobbling from side to side, it should be fine.
The best way to judge the health of a diff is to inspect the wear patterns on the pinion and ring gear teeth.
Posted: Feb 20, 2013 12:34 PM
by Bill in MN
I can see no wear in either the ring or pinion. It's loose enough to clank when I engage the trans, however, and translates to about 1/8" inch slop in the drive shaft.
It may in fact be normal. I have 0 sound insulation in the car, the tunnel's made of core and kevlar so every driveline noise resonates like crazy. It is not a quiet environment.
Posted: Feb 20, 2013 12:39 PM
by tsmall07
I'm not sure what the lash is supposed to be for that diff, but I've typically seen it between .008 and .012 or so. You could pull the diff cover and measure it if you're concerned. You could also take pictures of the ring gear and post what the tooth wear pattern looks like.
Here is an example of what the wear pattern should look like and what it can look like if there is a problem:
Posted: Feb 20, 2013 1:01 PM
by turbodan
In the absence of radial play or irregular wear on the ring and pinion, I'd say its almost certainly fine.
Posted: Feb 20, 2013 1:07 PM
by Bill in MN
Posted: Feb 20, 2013 1:22 PM
by tsmall07
That looks ok to me, but it's difficult to see if the wear pattern has changed. It might be worth it to paint up the teeth to see what the wear pattern is now. They make a special paint for it.
Posted: Feb 20, 2013 1:35 PM
by Bill in MN
It's tough to see in the flash but looking at it in good light it's not worth messing with. There are no abnormal wear patterns. I kinda doubt it's going to break.
Posted: Feb 20, 2013 2:15 PM
by tsmall07
Bill in MN wrote: I kinda doubt it's going to break.
I agree.
Posted: Feb 20, 2013 3:54 PM
by ElGuappo
If it ain't broke, fix it until it is...
Posted: Feb 20, 2013 5:13 PM
by Brad D.
ElGuappo wrote:If it ain't broke, fix it until it is...
I do that way too often.
Posted: Feb 20, 2013 5:47 PM
by demetk
tsmall07 wrote:
How do you move the pinion away or toward the gear?
How do you move the gear away or toward the pinion?
Posted: Feb 20, 2013 7:07 PM
by mooseheadm5
demetk wrote:
How do you move the pinion away or toward the gear?
How do you move the gear away or toward the pinion?
Shims.
Posted: Feb 20, 2013 7:49 PM
by demetk
mooseheadm5 wrote:demetk wrote:
How do you move the pinion away or toward the gear?
How do you move the gear away or toward the pinion?
Shims.
Wow really?
Posted: Feb 20, 2013 7:56 PM
by mooseheadm5
I'm really tired. I can't tell if you are serious or not.
Posted: Feb 20, 2013 9:17 PM
by demetk
mooseheadm5 wrote:I'm really tired. I can't tell if you are serious or not.
Not serious. You need to get some rest Moose, but if you're like me maybe you won't.
Posted: Feb 20, 2013 9:18 PM
by mooseheadm5
Ahh, OK. I've been crawling around inside of a Blackhawk for a couple of days after getting no sleep for a couple of months.
Posted: Feb 20, 2013 10:54 PM
by tsmall07
demetk wrote:mooseheadm5 wrote:I'm really tired. I can't tell if you are serious or not.
Not serious. You need to get some rest Moose, but if you're like me maybe you won't.
Why did you ask the question if you're not serious?
Posted: Feb 20, 2013 11:24 PM
by TheLazyDog
Guys... he's been Demet for as long as I remember.
Posted: Feb 20, 2013 11:28 PM
by demetk
tsmall07 wrote:demetk wrote:mooseheadm5 wrote:I'm really tired. I can't tell if you are serious or not.
Not serious. You need to get some rest Moose, but if you're like me maybe you won't.
Why did you ask the question if you're not serious?
Posted: Feb 21, 2013 12:02 AM
by mooseheadm5
Well the serious answer is still shims.
Posted: Feb 21, 2013 10:02 AM
by tsmall07
mooseheadm5 wrote:Well the serious answer is still shims.
SRSLY
