what to look for in 3rd?

[booger1]

I tore my front axle down, got the 3rd out and can't find anything wrong.  what do I look for i a 3rd?  before it had a lot of slack in it and made a grinding noise, and jerked the truck around.  now with it out of the axle, I turn it and it moves freely and doesn't look bad.  it isn't mismatched gears, because I didn't have the rear driveshaft in yet.

[BCD]

Were you driving on pavement with only front wheel drive, or dirt. If pavement, I would suspect that the jerking, grinding could occur. Otherwise look for uneven wear on the R&P. were the gears just installed? If so were they done correctly by someone who knows how to do them? Also check the spider gears if you don't have a locker in there and see if they spin freely. If you have a locker and were driving in Front WD on pavement then I woudl definately do a quick inspection and try it on dirt.
-Brian

[booger1]

factory front 4.10. pavement. I don't see any uneven wear.  inspected the axles those are good.  don't know if it will help, but when it started grinding, it still did it for a few seconds after I hold the clutch in.  it has to be somewhere in the 3rd though, doesn't it?  if yall are positive it is the 3rd, I can get a 3rd locally here.

[BCD]

Like I said, it wouldn't surprise me if it was caused by how much traction your front tires get on pavement, but to explore other options, lets check your t-case. since you have neither driveshaft connected right now, hop in your truck and fire it up, put it in 4wd, and first gear (make sure your drive shafts are disconnected or you'll hear more banging than you care to know about) and see if it still grinds. Who knows it could be the 4wd part of the t-case, kind of a long shot though.

[booger1]

nope, already did that, besides I drove the truck around a few weeks ago and it was fine with ifs.  it has to be in the front axle, because it only did that after the sas.  what would cause all that slack.  I could turn the front driveshaft with the hubs locked and it would turn quite a bit more than the rear 3rd.  is the 3rd the only thing that could cause slack in it like that?

[notajeep]

Sounds like the gears ar worn.  Maybe you can shim it more to tighten them up a little...... But while you are in there, just put in a set of 5.29's.

[Wheeler Peeler]

The gears in the rear probebly do not mach. it will not mater if the D shaft was not in on pavemet it will only save the T case or tran. I did this one time if you whant to chek you can take the old ifs therd apart and see the gears in it. but that is what I would check.