lualchro

Quick question

I have an 89 4.0 Renix with vacuum disconnect front differential.
Someone has removed some of the vacuum lines, and currently there are no vacuum lines to the front differential or the blower inside the cabin.

My question is regarding the front differential, if no vacuum is applied when selecting Hi or Lo 4WD, what will be the effect?
I got two thoughts:
1. Front diff will act as an open differential, allowing for one of the wheels to spin
2. Right tire will not engage, being a 4X3 traction

please help me to get me out of my ignorance!!!

I plan to run a manual disconnect, just want to know what is the current situation with no vacuum to the diff.

Thanks a lot

cruiser54

Here's how you fix it. If you don't do this, and have a vacuum issue, you will have only 2wd.

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

lualchro

Thanks a lot Cruiser

One more question to understand this a little better.

The vacuum lock, or the locking collar will connect the front differential with the driveshaft coming from the transfer, is that correct?

Also, comes to my mind, normally on my Jeep, going into 4WD will require two actions together, the 4WD to be engage by the driver and the locking collar to displace and engage the front diff to the transfer, correct?

do you recommend to leave it in the lock position permanently, or with some time to correct it either with the vacuum or the manual cable fix?

cruiser54

No. The passenger front axle is 2 pieces. It connects the 2 pieces together. The lever you pull in the cabin engages the transfer case to teh front driveshaft.

Leave it in the locked position per the write-up. It's what the factory did in about 1991 when they realized what a mistake the original design was.

lualchro

Thanks a lot for the info Cruiser