Noise identification lol good luck

[crazy4offroad]

You should be able to turn the input shaft back and forth while you work the shifter to shift it. If the input don't spin, or the output(s) don't spin, I would begin to suspect the t-case locked up (broke chain bunched up and locked it up?) and caused the rear end to break.

 

[usar17]

No....I reassembled everything so I can't spin the input or output by hand now. Before I attached the rear drive shaft I thought Id test the tcase by attempting to pull it with the front axle. Well that caused some grinding sounds so I shut it off. Tcase is now hard to shift again. Was able to work it into 2hi. Then tested it and that's when I snapped the rear. Idk wtf gave me bad luck this month.

 

[usar17]

Ok new diagnosis. Wiggled the drive shaft and the whole truck while in neutral. Tcase now shifts freely again. Got it to move forward in 2hi for a little before the rear began free spinning again. 4hi and low work great. Gonna pop of the rear cover and take a gander.

 

[usar17]

OOOHHH THE HUMANITY!!!!!!! hahaha

Well the spiders grenaded in the differential assembly.

Here is my hyposis:

1. Spider pin was bent causing grinding at high speeds with no power on the system

2. when the spiders gave the Tcase freaked

3. Disessembly was pointless of the Tcase, BUT removal of the shaft allowed me to get the tcase back in sync with the overall system.


Everything seems to work great exept the rear axle is shot. THANK GOD JUST THE SPIDERS haha. Guess I'll still just use this time to swap in a 3/4 ton suspension and 14 bolt ff 4.10 unless any of my friends around here have a spare diff and spiders.

 

[crazy4offroad]

Wow you're lucky you didn't lose an axleshaft, with the wheel still attached!! Is that yellow marking paint I see on the ring gear teeth? Is it possible someone set up the gears wrong? Also I don't see a crosspin bolt, common mistake, not putting locktite on it!!!

 

[usar17]

What u see is everything. I guess someone did a horrible rebuild on this. Bastards.

 

[crazy4offroad]

Did you check the pinion nut? Or see if the pinion is loose?

 

[foamypirate]

Here I was beginning to think I was way off base when I suggested it was the rear diff, lol.

 

[HotRodPC]

Real lucky. I am suprised when that crossshaft came out, and as the carrier was spinning at highway speed, it didn't break the carrier. Thankfully the shaft sheared instead, but yep, does look like someone didn't locktite the retaining bolt, and that allowed the crossshaft to fall out. A trip to a pull it yard, a few pocket parts and you're up and running again. If you do this, be sure to get all 4 spiders from the same axle. Don't mix and match them if used.
Also, make sure you're getting 28 splines outter spiders and not 30 or your axles won't go back in. I think its 87 and down are 28, 88 and up are 30 spline.

 

[usar17]

Sorry third pic didn't post....the carrier is cracked and missing a chunk too

 

[usar17]

ok the first photo is the carrier now. The second is a photo i took last month when i change the fluid. (Sound was there before i did that, so i know i didn't cause this lol)

 

[HotRodPC]

yeah, I figured it would be hard to shear that crossshaft by hitting the case and not damage the carrier too. Now you get to proceed with the 3/4 ton axle huh?

 

[usar17]

Trying to shop around now.

Anyone ever buy an old military 3/4 ton for parts? They are going for around 200$ here


Any reason why they wouldn't work? Are they any different

 

[HotRodPC]

Trying to shop around now.

Anyone ever buy an old military 3/4 ton for parts? They are going for around 200$ here


Any reason why they wouldn't work? Are they any different

A parts CUCV for $200??? By all those you can and fast !!!

If it's a true 3/4 ton and not a 1 ton rated at 1.25 as in the CUCV, then yes it'll work.

You can get a rear end out of a C20 of a K20 and it bolt right in with a driveshaft mod at the rear, or if you can get the driveshaft from that vehicle if it has the same drivetrain components as yours. I think you have to shorten the driveshaft a bit and I'd have the 3/4 ton U joint put on the end of the shaft too, otherwise you'll have to run a conversion U joint. Those are usually a hassle to get a discount parts stores, and about double in cost too.

 

[usar17]

How can I tell with these military trucks. What are the numbers and models etc.