4WD... need help.

[Joopin]

I posted a question last week about my 4WD going out, and someone responded to check my vaccum lines first to make sure there was no leak. Well today I finally did it, I had a guy in my jeep putting it from 4Hi to 4Lo... got sucktion on both. So that means I have no problems with my lines... what else could be causing this problem? Would it be in the t-case or the front end? Need fluid in the T-case maybe? Any ideas would help me out. I'm in the dark.

 

[frankiefire702]

if you're getting vaccum from the lines i would check the vaccum motor for the diconnect on the front axle next. from what i'm told they often go bad on the yj's. i just changed my little brothers out the other day on his 94 yj.

 

[west747]

yeah usually it is the shifter fork that is the culprit. take the motor out and spray her with some gold old wd-40 and work the fork back and forth a couple times. if it were me i would slide that fork over to the locked position and fix it in place.

 

[Joopin]

I just got done reading my chiltons repair manual, and it said "the shift motor should maintain the vacuum applied to the rear port for a minimum of 30 seconds, if the motor doesn't maintain the vacuum, replace it."

I didn't check for 30 seconds, I only tested to see if it was sucking. So it may be bad.

What is this shifter fork thing you are talking about west? I don't see it in any of the diagrams in the manual.

 

[monsterrd]

I had nothing but problems with my whole vaccum system, got a posi-lok setup for $150.00 no probs since, it takes about an hour to install. 8) 8) 8)

 

[west747]

take the vacum motor off of the axle housing and youll know what i am talking about right away.. the forks roll is to slide a sleeve over both axle shafts locking them together.

 

[Joopin]

I think I am going to try to fix the vacuum for now, I was thinking of getting a hub setup but maybe later. Plus I like changing over inside. Monsterrd, you installed them yourself?

 

[Bounty__Hunter]

Transmission spade plug?

Pull the 4 bolts holding the vacuum shift motor to the front axle, and catch what little gear oil comes out. Work the shift fork by hand while spraying WD40 into the vacuum ports. This will get your moisture out and lubricate the shift fork. Reinstall and it should work fine.

Worse case scenario is the vacuum diaghram is shot, but I've never seen it.

 

[monsterrd]

I think you are talking about posi-trac, posi lok is a cable that hooks to your shift fork, released from inside ,eliminates all vac. problems,since you no longer use vacuum. 8) 8) 8)

 

[Joopin]

Greasy...

Thanks guys, I'm gonna fiddle with the fork today. I hope it works!

 

[Bounty__Hunter]

Let us know how it turns out, and if you need any more help.

 

[Snitty]

Block Heater

if it is vacuum problems... a cable system will solve it all.. and give you 2wd lo capability

 

[Joopin]

Well I come to find out that the guy who put in my sye and lengthend my front shaft put some sort of nut or something on the t case shifter cause he thought it was too short after my lift. I told him that there is no body lift on it at all and no tcase drop so it should have been fine. He may have screwed it up in doing that, he is going to look at it monday morning since I am getting the rear main seal fixed at a shop literally next door to his shop. If he screwed up, then I get it fixed for free...

Whats the big deal about 2Lo anyways? I don't see any advantage, if you are going to use low then most likely you will need all 4 wheels goin'... just my thought.

 

[Snitty]

sometimes you want the low speed without burning your clutch by holing it halfway... and the high torque for pulling something a short distance, or for utility reasons... and often times... when you want that, you are on pavement, and we know that pavement and 4wd are a no no

 

[Joopin]

Aaah, touche' Mr. Snitty... touche'.

 

[Bounty__Hunter]

I use the manual disconnect on the front axle for 3wd, since the front diff is welded. Makes tight turns on the trail a LOT easier. Only need 3wd about 5% of the time on the trail.

 

[Joopin]

Well it ended up not having to do with the vacuum at all. I took it to a guy to check my rear main seal leak, I mentioed that the 4wd wasn't working and he just fixed it without me even asking. He said there was a lock nut missing and a cable from the t-case to the transmission was disconnected. I have no idea where that stuff is or what he meant but its fixed! Thanks for the input though guys.

 

[Bounty__Hunter]

Sounds like maybe the nut on the transfer case shifter rod was missing, allowing the rod to slip when you move the transfer case lever.