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Want to get rid of my Vacuum assist

RabidRabit said:
What do I need to do to change my D30 from a vacuum assist to a non vacuum assist?
Click to expand...

Ya had me worried there - you want to go from CAD to non-CAD.

A couple ways to do it - you either run a manual control cable down to the CAD actuator and run it manually, you convert to non-CAD using later-model shafts, and I think there is a kit or two on the market that will give you a clean solution (but they're not horribly cheap.)

When you said "Vacuum assist," I thought you were talking about your brakes - to get rid of your vacuum assist, you'd have to install a hydraulic assist (GM calls it "Hydroboost") using boneyard parts. A lot more work - and you don't want to leave your rig with "manual" brakes, since the XJ (particularly the earlier years) are underbraked anyhow!
 
Justink said:
Heres a good write up:
http://www.comancheclub.com/forums/viewtopic.php?f=9&t=18415
Click to expand...

It appears this link is now dead but thanx for at least trying to send me in the right direction. I've looked at the JP mag article and I don't feel comfortable with the drill and pin idea, and don't want to pay the bux for the superior kit. I might as well go with Chrommoly axles if I'm going to spend bux. I mostly just wanted to upgrade the u-joints to the spicer 760 u-joints to save me from blowing the weak ones I have now.
I tried to find the following:
95 Wrangler ABS shaft to upgrade this axle to 297/760 joints and keep the disconnect feature.
Dana part numbers for this are 75589-1x for the right side and 75815-1x for the left.
To upgrade to the shafts with the bigger joints, you just need shafts from any TJ dana 30, or 92-95 XJ front shafts from a rig with ABS, or any 95 and up XJ shafts.
I had a hard time finding the axles I needed as no one wanted to sell just the axle stubs when parting out. I understand their reasoning as it would be harder to sell the axle tubes and diff without the axle, more of a hassle than most people want or need.
I have the 4x4posi cable but that doesn't deal with the weak u-joints. I ended up with the axles out of a 95 XJ with ABS. This D30 had no vacuum disconnect. So I can keep searching or go to the solid axle swap which I found a write up for here:
http://www.stu-offroad.com/axle/yjd30convert/yjconvert-1.htm
This looks the easiest so I'm going to give it a try, plus it's got pictures which is a big bonus to retards like me.
My goal is to keep my rig and it's build budget as low as I can. So far it's not being going that way as much as I'd like.
Hope this helps someone else that isn't into spending all their paychecks into upgrading the stock D30 the easiest and cheapest way possible.
Thanx to those that responded to the post.
 
I would then have to change the gears over, uninstall and reinstall the front end etc. I did get through with the link this time and it still doesn't get rid of the weak u-joints. I'm thinking that the way I'm going will be the cheapest and best way to go. Again I don't want to fork over the money for the Superior 30 kit or the Chrommoly axles. I'll have solid axles and bigger u-joints with very little effort or money. I'll also do away with the problem ridden vacuum disconnect, and I'll have a Posi4x4 that I can sell and make enough money for beer for the bar-b-que at the end of the day.
 
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One of the reasons to go non-disco front axles is that they have the larger 297 type joints. I have been wheeling XJ's for 13 years and have never seen the actual disconnect break, only the ujoint ears or right behind. I used to run a disco axle shaft from a SWB Jeep that had the 297 axles. Don't remember the year they came on but I am sure someone will chime in. Then you can keep the old small ujoint axle as a spare.

The easiest way to make it totally non-disco is to simply put washers on the shift fork shaft to force it to be engaged all the time.
 
For some reason 95 YJ comes to mind for a D30 CAD with 297s.
 
old_man said:
One of the reasons to go non-disco front axles is that they have the larger 297 type joints. I have been wheeling XJ's for 13 years and have never seen the actual disconnect break, only the ujoint ears or right behind. I used to run a disco axle shaft from a SWB Jeep that had the 297 axles. Don't remember the year they came on but I am sure someone will chime in. Then you can keep the old small ujoint axle as a spare.

The easiest way to make it totally non-disco is to simply put washers on the shift fork shaft to force it to be engaged all the time.
Click to expand...


I used the washer method for my D30 vacuum disco. A temp solution until I get done trussing my D30 non vacuum disco...Still on the work bench as of currently.

If you try to do the one piece conversion then keep in mind you have to install/replace the axle tube seals as well. They are a total PITA from what I researched thats what inspired me to do the washer method.
 
The disco is actually a stronger housing/bracket system.
 
I didnt really read through all the sugestions. I put a vac disco d30 in my 95 (free parts yay) and the motor was still good so i just pushed the collar over to lock the axle shaft and moved the shift fork over and plugged all the vac motor ports. I've beat on it a few times out and hasnt given me any trouble. Total cost = $0 stuff just sitting around the garage.
 
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