Bad spider gears?

89wrangler

89wrangler

Not a new member
Joined
Oct 22, 2005
Location
Bostic,NC
I am working on a 21 Gladiator for a buddy that has a really annoying vibration you can hear/feel when driving. He has had it worked on at various places and can’t get rid of the noise. I have it narrowed down to the spider gears in the front axle. The passenger side has the axle disconnect and everything is smooth when rotating the wheel.
On the driver side when rotating the hub, you can feel/ hear the ratcheting for the lack of better term. I removed caliper and bracket and ruled out wheel bearing. So I removed the diff cover and it appears to be the spider gears. You can rotate them about a 1/3rd of a turn, then they lock up/stick. Takes a lot of pressure to hold the ring gear to get them to go past that point and then they turn free again. There is some pitting, but nothing I see way out of the norm.
@Jody Treadway have you ever run into this? Could there be anything else causing them to not rotate freely. I am going to pull the axle shaft and see if it changes anything.

Any input would be appreciated! Thanks
 
Here is a video.


Axle removed, seems fine.
 
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Is it completely stock, or has someone been in there before? I wonder if it's missing the little washer/bearing things behind the spiders. No clue their official name.

1793471506747.png
 
It is stock. The washer is there. When I put the axle in I can turn it as normal. But when I put the hub on it binds up
 
How's the U-joint Feel?
 
Tube is bent?
 
U-joints are tight. Gears are tight, with hardly any wear. I am thinking bent tube as well.

Is there a way to check it?
 
89wrangler said:
U-joints are tight. Gears are tight, with hardly any wear. I am thinking bent tube as well.

Is there a way to check it?
Click to expand...
I use a measuring gauge that came with my frame machine to see if the axle tube is bent. You can use a level or a straight edge and cut you 3 or 4 dowels the same lenght about 12 inches long and space them out across the tube and level or straight edge to see if they all touch the same or one or 2 of the don't fit between them. Check the axle at different angles to see if it is bent.
 
To me this sounds like something is in the gear mesh at the root of a tooth. When the hub is installed it pushes the shaft in to where there is essentially zero lash in the spider gear mesh. Or, there is something amiss with the splines at once end or the other of the driver side shaft that pushes the shaft inward and tightens the spider gear mesh. Or a burr at the spider gear or inside the hub if the wheel bearing that causes the shaft to tighten up.

I would take a pick to the root of all the spider gears and see if there is anything crushed into the root between the teeth.
 
If you're in a position where you can easily install/remove the axleshaft, turn it until it starts to bind, mark that tooth, then remove the shaft, rotate 90 or 180 degrees, reinstall, and see if your bind point moves with the shaft. If it doesn't, it's probably in the gears like @OnlyOneDR said. Easiest fix is clearly a selectable locker though. :D
 
There is definatley some wear on the teeth where bind is happening.
I have a new axle assembly coming this week and can rule that out. (Amazon with free returns for the win)

An interesting note is that the driver side tube is is fully weled to the pumpkin. I dont think this is normal from a few pics I have seen.

I am thinking just throw a lunchbox locker in there and move on. He doesnt take it off road, it has an axle disconnect, and if he does need 4WD, it is just a bonus.

Here are pics of the spiders
1793739418590.jpeg

1793739436276.jpeg
 
I guess I missed the memo when manufacturers started cheaping out and not machining the spiders. Those are just cast parts without any finishing; the spots you are depicting are casting flaws that have been there since day 1 (never should have passed QA/QC checks). Looks like gas porosity. To me, I would just carefully take a dremel tool or die-grinder with a small sanding disk and slowly dress it until it does not bind. The gears do go round and round without load when the axle is disconnected but do not spin fast under load when the axle is connected together. Thus, I would say the risk is seriously low for an future damage. A spider gear kit must be pretty cheap, you can always just swap them out.
 
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