Posi-lok issues?

[IslanderOffRoad]

I just finished insalling a 4x4 Posi-Lok system on my Jeep.

I've got a 94 Cherokee, which has an 89 Disco front axle in it. I bough this axle as it was cheaper than re-gearing to 4.10s. I bought the posi lok setup as 2-low appealed to me.

Anyways, I've found a few issues with it.

1. I bought the one for lifted Jeeps, it states its for 3" lifts, I'm at about 4.5", and the cabe is way too long

2. I first installed it with the axle disengaged. When I went to test it, I found that it would not engage. I re-installed it with the axle engaged, and found that it will not disengage.

I thought no big deal, at least my 4wd works. Then I took it for a test drive. while the collar at the CAD was engaged when I put it on, it seems like it is not now. I put it in 4wd and just got vibrations and grinding noises, obviously not right.

Did anyone else have issues when installing one of these? What should I do to correct this?

Thanks in advance.

 

[Foxmotorsport]

I've had mine for about 4 month's, no engagement issues, but, I do agree that the cable seemed way long for the app.... I currently have 4 and a bit", and had a helluva time hiding/routing the cable

 

[Rev Den]

Sounds like it is one of 3 things...

Needs to be adjusted.

Is missing one of the three snap rings that hold the fork in place.

The AL fork is worn and needs to be replaced, preferably with the steel fork.


Rev

 

[OverlandZJ]

In addition to Rev's...i'd check the cable routing. A sharp turn in the cable can tighten it up and make it tough to operate.

 

[IslanderOffRoad]

Sounds like it is one of 3 things...

Needs to be adjusted.

Is missing one of the three snap rings that hold the fork in place.

The AL fork is worn and needs to be replaced, preferably with the steel fork.


Rev

Snaps rings are all there, fork seems ok, but I'm not sure how to tell if its worn.

How do I adjust it?

 

[Rev Den]

You can tell if the fork iw worn because it will rock on the shaft.
It is adjusted by screwing or unscrewing the cable from the housing?

No manual?

Rev

 

[OverlandZJ]

Heres how i adjusted my son's in his YJ.

The pull knob, make sure it is fully seated IN and turned all the way to the right.

Adjust the threaded end of cable into the housing till the 3rd clip almost touches the side of the housing. Tighten locknut.

Install the new housing to axle making sure the fork sits in valley of the shaft collar. Tighten the bolts up and you should be ok.

Now keep in mind you may not be able to engage or disengage while sitting still, we have had an easier time of it when slow crawling and pulling/pushing the control knob GENTLY. If you try to force it your going to bust the stock type forks.

 

[IslanderOffRoad]

You can tell if the fork iw worn because it will rock on the shaft.
It is adjusted by screwing or unscrewing the cable from the housing?

No manual?

Rev

I have the instructions, but I'm incredibly dissapointed in them. They're vague and dont give you much information IMO. It says things like "force may be necessary" to remove the vaccum motor, but gives no advice on how to accomplish this.

I set it up as the manual said, 3rd clip touching the side of the housing, tightened the locknut and installed into the valley.

Maybe the fork is worn... I guess I'll pull it apart and check again.

 

[MudDawg]

Hopefully the cable hasn't gotten against the exhaust an gotten burned...I have found with mine, the best way to get clean engagement is while rolling slowly in 2wd....and disengage it in a similar way...I broke several forks trying to engage it in 4x4.

 

[IslanderOffRoad]

Hopefully the cable hasn't gotten against the exhaust an gotten burned...I have found with mine, the best way to get clean engagement is while rolling slowly in 2wd....and disengage it in a similar way...I broke several forks trying to engage it in 4x4.

I've only driven it for about 5 min since installing it, so I doubt the exhaust burned it already.

I should have searched more before I bought this... all the brolken forks and difficulty engaging make me think I should have just put the one piece shaft in.

 

[Rev Den]

I put in the steel fork when installing mine, and never had an issue with it in 5 years.

Rev

 

[OverlandZJ]

http://www.naxja.org/forum/showthread.php?t=56016&highlight=posi

In the above link XJeeper links to a source for the HD Fork cheaply. The post itself may help you.

 

[IslanderOffRoad]

ok... good news bad news time.

I drove the jeep to a buddy's house tonight, and after some driving things must have loosened up as I can now engage and disengage the posi-lok... it makes a bit of a noise on engagement, but this seems normal as a "non moving" part (the collar) is trying to slide on to a "moving" part (the intermediate shaft)

The bad news is when i put it in 4wd it still doesnt feel right, the jeep wants to stop right away, just slows down as I drive in 4wd and makes a grinding noise. I bought the front axle used from the same person I bought the rear axle from, was told both were 4.10... I'm thinking the front may not be 4.10. Does this sound like a symptom of running mismatched axles, or is there an issue with the axle itself (i.e chipped teeth on the pinion gear, damaged shafts, etc)?

 

[jrowell]

ok... good news bad news time.

I drove the jeep to a buddy's house tonight, and after some driving things must have loosened up as I can now engage and disengage the posi-lok... it makes a bit of a noise on engagement, but this seems normal as a "non moving" part (the collar) is trying to slide on to a "moving" part (the intermediate shaft)

The bad news is when i put it in 4wd it still doesnt feel right, the jeep wants to stop right away, just slows down as I drive in 4wd and makes a grinding noise. I bought the front axle used from the same person I bought the rear axle from, was told both were 4.10... I'm thinking the front may not be 4.10. Does this sound like a symptom of running mismatched axles, or is there an issue with the axle itself (i.e chipped teeth on the pinion gear, damaged shafts, etc)?

The Posi lok will not make any noise when engaging. The collar is actually spinning at about the same speed as the axle. Once it lines up it will slip in place. Should not take much force on the lever. you should be moving and might need to bump the gas to get it in. If you are hearing any noise, something else is wrong, which I'm guessing you are starting to figure out.
I've had my Posi for 6 years, and just broke my first fork. Time for a steel one!

 

[IslanderOffRoad]

Did some troubleshooting this weekend...

Opened up the posi lok unit, opened the diff as well... diff is fine, no chipped teeth, no metal parts in the bottom. I manually engaged the collar and verified that everything works fine when spinning the tires or the DS, no noises at that time

Put it back together and I had the same issue as before... briefly. The jeep was clunking, felt like the front axle was locking up/wouldnt turn, and was pulling hard to the rt. One big final clunk, and then it drove normally. However... now the posi lok cable engages with no issue, and if I'm in 4wd and take a tight turn I don't get any binding... leading me to believe something is seriously effed up in my front axle. Did I break the fork? Or something worse?

No weird noises when driving, tracks straight, it just seems like the 4wd isnt engaging at all now. I've never had t-case issues so I'd be surprised if this came out of nowhere, it has to be the new axle.

I'm about ready to give up and take this to a shop to fix... I'm tired of screwing with it and just want to wheel the Jeep.

 

[IslanderOffRoad]

Update

Replaced the shift fork with a cast iron one.... the old fork had broken in that last big clunk I heard.

However.

I'm back to my originial issues. The 4wd Is working, and the posi-lok works, however it makes a noise when engaging, and while I'm in 4wd the Jeep pulls to the right and makes a whining/binding noise. This is while driving (or attempting to) drive straight. I noticed that the collar for the disconnect was stuck all the way right, and it took some serious prying to get it to move.

I'm positive at this point the issue is with the axle. I also get a slight death wobble from the rt front at around 40mph.

Whats the best course of action on this? What part is likely causing the problem?