Front end broke, transfer case shift fork confirmed too I think.

[lowtrac]

I was driving Saturday morning and started feeling and hearing some popping that was not normal. The previous owner didn't take very good care of it so I've been fixing little things along the way. Pops and clunks are not uncommon but this was different. I pulled into a parking space and slid under the front to shake some things. I noticed the driver's side sway bar end link was loose, but I had it disconnected it when changing the CV axle on that side so I wasn't too alarmed. Then I noticed the CV boot on the hub-end of the axle was twisted. It looked like the hub spun and the diff didn't or vice-versa. I then tried to limp it home but only got about 200 feet before it quit pulling. I tried all three 4WD modes and nothing. Finally after sitting blocking traffic for a few minutes and moving the transfer case from neutral back to 4-high lock I was able to start moving again so I pulled it into a parking lot and it quit pulling again.

Three towing companies I called said it'd be "a couple of hours" before they could get there, so I called in a family member with a tow strap. I put the transfer case and transmission in neutral and he pulled me home. Something in the front end sounded like rocks in a blender while being pulled. I know I could have potentially damaged something worse by pulling it, but I figured I didn't have much to lose.

I had suspected a broken shift fork prior to this since I experience regular front end binding. I assume that's confirmed at this point (or some other TC issue) since it wouldn't pull in 4HL or 4LL either. Obviously there's something broken in the front end too, so my plan of attack is as follows:

Remove both CV axles, drain diff and open the cover to survey the damage.
Drop transfer case and replace shift fork
Reinstall transfer case and verify function by driving in 4HL
Address the broken parts in the front end. I'm assuming a rebuild will be necessary.

Does this seem sound logically? I don't have a ton of money so I'm trying to repair rather than replace as much as possible. Thankfully I have another vehicle to drive so I have the luxury of time somewhat, but I'd like to get it moving under its own power soon.

Any other ideas?

 

[atvspeed4]

Check front drive shaft CV up near the transfercase. That can produce the same sound and issue you described.

A broken CV axle can also do the same thing

Ive broken the aluminum "coupler" block and end of splined shaft that is on the long side of the diff (driverside) same symptoms.

If all that checks out as okay then remove diff and open up to check for damage

 

[alrock]

atvspeed is right on target.

Your attack plan is good as you're hitting the three most likely culprits - CVs, diff, transfer case - and you'll be handling the fourth item, the prop shaft. It's possible that you had a diff or TC failure that caused a CV failure, or a CV failure that maybe caused a failure upstream.

 

[4speedfunk]

No mystery...the twisted cv boot clearly points to a broken CV on the outer end of the DS half-shaft. I'm betting that's all (at least initially). Seems logical to start with the DS half shaft...I say this because that's what you just recently replaced, and lots of guys have issues with aftermarket replacement shafts. Plus the twisted boot cannot happen unless the cv itself has blown and separated. This would most certainly make popping and grinding sounds. It would also make the drivetrain "freewheel" in 4Hi-street mode.

If you could cycle the t-case through all modes, it's probably not the shift fork. Usually a front driveline break will free spin in 4Hi-street mode, and you must use either lock mode to move. Sometimes there will be severe binding...but only until you grind the broken stuff into dust. It gets smoother after that! You probably did that on the way home. That's the downside of full time 4wd.

 

[lowtrac]

Thanks guys. I'm planning on diving into it in the morning. As for the shift fork, it was freewheeling in all 4wd modes, but sometimes it would move. That's why I'm thinking it's broken. Doesn't it engage a sleeve in there that moves to lock the TC? Maybe the fork can move it some but not all the way so it'll slip in and out of 4H and 4HL.

 

[atvspeed4]

Thanks guys. I'm planning on diving into it in the morning. As for the shift fork, it was freewheeling in all 4wd modes, but sometimes it would move. That's why I'm thinking it's broken. Doesn't it engage a sleeve in there that moves to lock the TC? Maybe the fork can move it some but not all the way so it'll slip in and out of 4H and 4HL.

Sometimes you cannot shift into 4hi lock when a CV axle or driveshaft is broken. The collar wont shift over correctly due to the difference in speed of the components rotating/ accelerating.

 

[4speedfunk]

Yeah that's a good point. You might have to shut it off and cycle the t-case with the key on but, not running.


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[lowtrac]

Outer axle CV is in chunks. Everything else seems pretty good except for totally blown out center diff bushing. Still buttoning stuff up and working on temp fix for the bushing. Will post a couple of videos later.


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[lowtrac]

4speedfunk wins again. Also I believe atvspeed4 was correct on the 4H/4HL thing.

I jacked it up this morning and once the driver's side tire was off the ground, this:

[video=youtube;prV9MCTFwws]https://www.youtube.com/watch?v=prV9MCTFwws&feature=youtu.be[/video]

[video=youtube;RWfNcPuX7K0]https://www.youtube.com/watch?v=RWfNcPuX7K0[/video]

I know the center diff bushing is shot, but once I got the new CV installed the park to reverse to drive clunk was MUCH more pronounced than before. I've got a replacement bushing, but needed a shadetree fix until I can get access to a press. I was trying to figure out something that I could use as a spacer to lock the diff down to the crossmember. I used a hole saw that was large enough to contact the metal of the crossmember and had a hole in it large enough for the factory bolt.



Everything seems fine after a short test drive. I'll stay close to home with it for a few days to make sure though.