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Discussion Starter · #1 ·
Hi all,

(past references are below)

So, the mechanic said that he pulled the carrier, and that everything seems to be wearing in ok (course at this point I had only driven 20 miles or so) . . he said run it for a few hundred miles then if it hasn't changed then he'll break it down again.

Here is what I have done since then (because after 100, nothing changed):

I changed the pinion angle (I rigged a wedge between the axle housing flange and the leaf springs) and it looked nearly perfectly straight (pinion used to be down pointed a little when everything was on the ground). No change!

I pulled the left axle, bearning seems happy, and it looks like it's a "maint free" bearing as the rollers are not visible and I don't think I could pack it with grease.

Here's where it get's interesting:
I pulled the left axle and dropped the driveshaft, then started playing with the wheel and pinion. Rotating the wheel or pinion without touching the other, everything spins rather freely.
Rotating the right wheel as if the car was going backwards (counter clock on right wheel) and putting tension on the pinion (going downhill backwards with engine breaking), no prob, maybe a slight drag. Rotating the pinion with tension on the wheel in that direction is basically the same (backing the car up uphill).
Now, if the system is moving so that the car would be moving forward, it changes a little. Moving the pinion with drag on the wheel is "perfect" glide (forward acceleration). Moving the wheel forward with tension on the pinion BIND!!! I can pretty much lock the wheel by tensioning the pinion. . I can at this point let go of the pinion and the wheel is still stuck. Increasing the force on the wheel will break the bind.
I note that everything was done with my two arms and hands.

So, my hypothesis is that the vibration/moaning sound only on coast is the continuous bind/release cycle. Any ideas what this is?

Also to note, I put the axle back on, rotatied both tires in both direction while putting tension on the other glides effortlessly.

Another note: I have noticed that there is a little play in the system (turning the wheel will move a little before the pinion starts moving, then the right wheel start moving after both move a little). It doesn't seem like a lot, but it definitely isn't "instantaneous".

Thanks for advance and for sticking through all of the details!

past threads for reference:

2,217 Posts
It sounds to me like the carrier bearings are not set up properly. When you "load" the gear set it will try to push the gears apart and that load is captured by the bearings. There is a delicate ballance between the proper preload on the bearings, and moving the carrier sideways to adjust the mesh, when setting up the gearset.

If the bearing preload is too loose then "loading" the gears by acceleration can push it into the correct mesh, and "unloading" the gears by deceleration can push it out of correct mesh.

If your gear guy knows what the heck he's doing he should be able to read the mesh in the gears and see what's going on. If he can't see it in the mesh by 100 miles, then you need a new gear guy.

Discussion Starter · #3 ·
ok, makes sense, I'll get a few more miles on (I forgot to change the speedo gears so miles are accumulating on the odo faster than normal) to make sure the wear is obvious and take it back in, if he doesn't figure it out I'll have to run over to Currie or find someone else. Annoying.

Thanks wisperer
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