No more 4 wheel peel?

[Joopin]

I was driving home from work today when I got the hankering to put my YJ in 4Hi. I did so and started off again. I looked at my dash to see that the 4wd light wasn't on. I put it back in 2wd and drove home. When I got there I put it in 4wd again, drove, nothing. Then I tried 4Lo, rolled, the light DID come on. So I tried the 4Hi again, nothing. Then 4Lo and nothing.

This whole time it never seemed to "lock in" the way it used to... the Tcase shifter that is.

Now a couple weeks ago after I did my soa the 4Hi was working fine, I drove it for a week in "front wheel drive" even.

What happened here? Did the vaccum system finally go? Is there a way I can be sure it went if it did? I have no problem putting in hubs, I have heard the vaccum was bound to go so I have been prepared for this mentally, but my wallet is not. Any ideas?

 

[redrooster]

Take the vacuum hose off and put your finger over while getting one of your buddies to shift it. Another test is lock it in, get in some wet grass and stand on it while looking out the window. If you get dirt in your face then it's working.
Seriously, do the vacuum check first.

 

[Bounty__Hunter]

Manual hubs wouldn't be worth it for me, the vacuum system is easy to troubleshoot and work on. If you have an open diff or LS in the front you can always install a TJ or XJ passenger side axle shaft and cap off the vacuum disconnect.

Pull the vacuum lines from the front axle and have somebody shift from 2wd to 4wd and back with the engine running. Vacuum should be strong in one line for 2wd, and the other for 4wd. If not look for leaks in the vacuum lines. If the lines check out and you have manifold vacuum to the transfer case, then the vacuum switch in the top of the transfer case is probably bad.

 

[Joopin]

Why do so many people switch to manual hubs then? Don't get me wrong, I would rather just stay in the jeep and do the switch than go out to lock em in. I do have an open front diff, but I don't know what you mean by capping off the vacuum disconnect, what would be the purpose? I havn't fooled around with this part of the jeep yet, so I'm about to get a crash course in it. I have been learning about jeeps by working on all the crap that goes wrong with mine! Thanks for the input by the way. Keep it comin though!

 

[Snitty]

by "capping it off" he means to replace the 2 piece axle shaft of the yj, with a one piece axle from a tj or an xj... to do this, you remove the shift fork, and "cap off" the hole where it used to be bolted in... this makes the passenger side always engaged, and the 4x4 system would now be selected only at the transfercase... you MAY have to balance your front driveshaft for this, since the driveshaft will always be spinning.... but i would prefer to go with the manual disconnect before trying this

 

[skyjeeper]

get a posi-lok. it eliminates the vacuum actuator and replaces it with a manual fork. it also gives you the option of 2wd low.

they run a little less than $200.

you can find them at most off-road suppliers, even on ebay.

http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&category=33731&item=2452318224

http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&category=33585&item=2452561128

i'd go with one if i was keeping the stock axles and ever ran into a problem with the vacuum actuator.[/url]

 

[Snitty]

or make one yourself for WAY less than that

 

[Bounty__Hunter]

you MAY have to balance your front driveshaft for this, since the driveshaft will always be spinning....

My front driveshaft spins all the time due to the Lincoln Locker, and have no vibes. There are balance weights on it ('95) so it appears balanced from the factory. I'm thinking it may be a myth that YJ front shafts were not factory balanced.

The vacuum system is easy to work on, just jump right in, I'll walk you through every step if need be. Once you're familiar with it you won't waste your time or money changing it.

 

[GreenReaper93]

How do you make one of those "Manual Disconnects" Snitty? I've been looking into making one, but can't find a link for it.