I had to do an axle swap(old one had a bent c-yolk). I didn't know that the old axle was straight when I bought the one I put on there. I do know they both have 3.55gears. I was wanting to know how to hook up the vacuum locker. Another thing I want to do is convert the vacuum for the straigh becuase I have heard the stock vacuum lockers can't hold up off-road. I would like to know if it is possible to convert my vacuum to straight? If not how do I hook up the vacuum? It is a 1995 XJ AW4 tans, NP242 t-case, d30 front, C8.25 rear.

 

All I can say is my 90 has 2 ports. One gets vacuum from the switch to engage it. The second port switches vacuum to the light switch when the fork has actually moved over, to let you know it went.

Confusing when your fork is broken, the 4WD light comes on, and you are still stuck! Hope this helps, D.

 

just take the vacuum motor apart and throw some washers in there, it will be like it didnt exsist

 

FUNNY! Are there more tricks to get up to 7 MPG?

 

The way to figure it out is to leave the engine running in 2WD and put your finger on the ends of the tubes. The one with vacuum goes on the passenger side. The one the has vacuum in 4WD goes on the driver side. As far as them holding up when wheeling, they do. That is probably the last part that will break. The only issue is when the vacuum motor gets a leak in it, then it won't work.

 

uh.. where do I put the washers??

 

thats what i did to mine, very easy!!.....theres a thread some where around here with the info on how to do it, theres also a few other ways other than washers...

 

Yeah, theres cable kits you can buy. A little pricey but better than sticking with vacuum. The reason for putting the disco in is to save gas and tires during cornering. With the axles connected all the time, the outside tire during turning wears faster due to the tires turning at the same speed. This is more effective if you have a front locker.

 

This is FREE:
https://www.cherokeeforum.com/f51/fr...ss-91-a-38629/

The above link makes the early XJ more like the later XJ. The ONLY way both front tires would always be turning the same speed would be if the front diff was locked or welded. The OP has the 242 TC with the "full time" 4wd option in addition to 4 hi and 4 low.

You could go the cable actuated route, but that doesn't seem necessary.

Later XJs didn't have vacuum disconnect and didn't suffer from poor fuel mileage or abnormal wear on tires. My '96 Sport is on its 4th set of tires and the first 3 sets averaged in excess of 50K miles per set without regular roatation.

 

Yeah, but if you have a detroit like I do... It's best to have the cable disco kit. Trust me on this one

 

i did this just after i got my jeep and havent looked back the only draw back i have is that i dont have a locker atleast i dont think i do but when i back up it feels like i drag the inside wheel every time like its in 4wd

 

My 84 and my 90 in (a combined), 48 years have had 1 broken fork, had it welded. The vacuum lines fall off about every 2 miles, or about 236,000 times! (I did put on a big zip-tie to hold them last month).

 

That vacuum disconnect front axle gave us fits at the dealership. Always failed on customers when it snowed and they needed their 4WD the most.

Factory had a weak shift fork problem. They bent.

Factory had a fork design problem which caused the slider gear to "stick" on the outer axle splines not allowing the vacuum to pull it to the inner axle and engage.

The vacuum plug on the shift motor always got deteriorated from oil spilling on it during oil changes due to the upside down oil filter on the 4.0s.

I just slide the gear over and I'm done with it. Takes a half hour if you've never done it before. There are some links that have been posted above and there is a write-up with photos in the "Technical Write Up" section on this forum.

 

95 didn't have the vac disco from factory. neither did the 242 option xj's.
you should install the cable because you won't have any vac lines from your t-case.

also, these vac axles use the smaller 260 joints, so adding a locker is only asking for broken u-joints... i've been there, broke a lot. now i have a straight axle in place (without the locker).

or you can just do the cheap perma-lock options using a gear clamp, washers or a simple bolt to hold the fork in the locked position.

 

Hey there cruser. So if I don't have a locking diff, you're suggesting just leaving the axle whole? So what's the down side, wonder why they designed it that way in the first place. Thanks, D.