Dana 30 Vacuum Disconnect Mod
#1
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Year: 1990
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Dana 30 Vacuum Disconnect Mod
Even though this is a "mod" it retains all the stock components,thats why I posted it in the OEM section. If this isnt appropriate,I ask that a mod move it.
So...That being said. I read up on this,and not sure it applies to all DANA 30 Front diffs,as it specifies RENIX ERA.
This applies to me as My XJ is a 90.
Reading this,the mod appears VERY simple.
Anyone ever performed it? Am I reading it correctly? I interpret that this will keep the front diff "locked" without installing a locker or any other aftermarket components.
If that is the case,how will driveability be on the street? Will there be binding when turning.Is this a "trail only" modification?
Is this an idea that could turn into a disaster(breakage),or could this mod be performed and the vehicle perform well on the street?
Anyway... Heres the write up.
http://emeraldgreen97.wordpress.com/...isconnect-mod/
Im very curious to know what the more experienced XJ owners have to say about this.
So...That being said. I read up on this,and not sure it applies to all DANA 30 Front diffs,as it specifies RENIX ERA.
This applies to me as My XJ is a 90.
Reading this,the mod appears VERY simple.
Anyone ever performed it? Am I reading it correctly? I interpret that this will keep the front diff "locked" without installing a locker or any other aftermarket components.
If that is the case,how will driveability be on the street? Will there be binding when turning.Is this a "trail only" modification?
Is this an idea that could turn into a disaster(breakage),or could this mod be performed and the vehicle perform well on the street?
Anyway... Heres the write up.
http://emeraldgreen97.wordpress.com/...isconnect-mod/
Im very curious to know what the more experienced XJ owners have to say about this.
#3
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Year: 1990
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It does not give you a "locker". It just keeps the right hand axle engaged all the time like the later models. Do it an don't look back as previously mentioned.
#5
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Not at all. It's NOT locking both sides of the diff together. It's locking the two halves of the right side axle together. Just do it.
#6
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Kind of a dumb question concerning the Vacuum stuff,but the write up doesnt cover it. Once you do this mod,where does the vacuum stuff come into play,or do you just ditch it(plug it)
So as I understand with this mod,when you want 4WD to be engaged,you just pull up on your lever in the console and go. No need for the vacuum to "slide" everything into place,which can take a couple of seconds, because the parts that "slide" are already engaged.Pulling up on the 4WD lever after this mod only engages the Transfercase...Correct?
This is more of a 4wd on demand modification?
Im totally planning on doing this mod,I just need (for some reason) to understand the concept of operation before the mod(stock configuration) and after the mod. Im just wierd like that. Id like to understand,so if I want to clue someone else in on the mod,I can explain what operational changes occur when the mod is completed.
I apologize for wanting to be so thorough. As I understand,this mod can be "Undone"... Correct? But really if the mod is an improvement,why would you want to go back to the stock configuration...
So as I understand with this mod,when you want 4WD to be engaged,you just pull up on your lever in the console and go. No need for the vacuum to "slide" everything into place,which can take a couple of seconds, because the parts that "slide" are already engaged.Pulling up on the 4WD lever after this mod only engages the Transfercase...Correct?
This is more of a 4wd on demand modification?
Im totally planning on doing this mod,I just need (for some reason) to understand the concept of operation before the mod(stock configuration) and after the mod. Im just wierd like that. Id like to understand,so if I want to clue someone else in on the mod,I can explain what operational changes occur when the mod is completed.
I apologize for wanting to be so thorough. As I understand,this mod can be "Undone"... Correct? But really if the mod is an improvement,why would you want to go back to the stock configuration...
Last edited by 90_cherokee; 10-12-2011 at 09:17 PM.
#7
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this mod just makes your pre-91 axle like the 91+ axles, jeep realized how crappy the vacuum stuff was and did away with it. and yes the mod makes the vacuum stuff unused. you will have no prob in 2wd after this mod as the spider gears in the axle will still make up for the difference in the tire speed during turning. so after this mod all you do is pop it in 4hi and bam instant 4x4 no time waiting for the little ring to line up.
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#8
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did this mod about 3 weeks after i bought my 90 havent looked back since
the only difference i have noticed is when i back up in gravel it makes like i have a locker and i know i dont have one so my only other think it could be is the ujoints
the only difference i have noticed is when i back up in gravel it makes like i have a locker and i know i dont have one so my only other think it could be is the ujoints
#10
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it does not lock the differental (unless u have a locker/lsd or something like that) it only makes the passenger side shaft solid
example take a 2wd with open diff and do a burn out and what happens only one wheel spins what happens is the path of lease resistance will spin well if u have a 2peice (or broke) axle your shaft will spininside the tube the only thing this will do is make a 2peice axle in to a 1 peice or solid axle
example take a 2wd with open diff and do a burn out and what happens only one wheel spins what happens is the path of lease resistance will spin well if u have a 2peice (or broke) axle your shaft will spininside the tube the only thing this will do is make a 2peice axle in to a 1 peice or solid axle
Last edited by K-SKI; 10-13-2011 at 06:06 AM.
#11
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Kind of a dumb question concerning the Vacuum stuff,but the write up doesnt cover it. Once you do this mod,where does the vacuum stuff come into play,or do you just ditch it(plug it)
So as I understand with this mod,when you want 4WD to be engaged,you just pull up on your lever in the console and go. No need for the vacuum to "slide" everything into place,which can take a couple of seconds, because the parts that "slide" are already engaged.Pulling up on the 4WD lever after this mod only engages the Transfercase...Correct?
This is more of a 4wd on demand modification?
Im totally planning on doing this mod,I just need (for some reason) to understand the concept of operation before the mod(stock configuration) and after the mod. Im just wierd like that. Id like to understand,so if I want to clue someone else in on the mod,I can explain what operational changes occur when the mod is completed.
I apologize for wanting to be so thorough. As I understand,this mod can be "Undone"... Correct? But really if the mod is an improvement,why would you want to go back to the stock configuration...
So as I understand with this mod,when you want 4WD to be engaged,you just pull up on your lever in the console and go. No need for the vacuum to "slide" everything into place,which can take a couple of seconds, because the parts that "slide" are already engaged.Pulling up on the 4WD lever after this mod only engages the Transfercase...Correct?
This is more of a 4wd on demand modification?
Im totally planning on doing this mod,I just need (for some reason) to understand the concept of operation before the mod(stock configuration) and after the mod. Im just wierd like that. Id like to understand,so if I want to clue someone else in on the mod,I can explain what operational changes occur when the mod is completed.
I apologize for wanting to be so thorough. As I understand,this mod can be "Undone"... Correct? But really if the mod is an improvement,why would you want to go back to the stock configuration...
There is a way you can plumb it to keep your 4wd light. I figure if you can't tell if you're in 4wd like we used to in the old days without a light, you oughta be driving a Honda. LOL The light is handy if you've got the NP242 t-case which has both full time and part time and your wife drives it.
#12
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I was going to do this but spent money on the vacuum motor instead. I kinda wish I had just clipped it locked but was weary of poor fuel mileage.
#13
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a "better" way of doing this is to remove the E-clips from the shaft which pushes the shift fork into place, and push the shift fork all the way into the engaged position, then reinstall the e-clips behind the shift fork. (it works I have done this on the trail when my old vac actuator gave up)
much better than having a foreign object (hose clamp) in there to possibly damage seals
much better than having a foreign object (hose clamp) in there to possibly damage seals
#14
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a "better" way of doing this is to remove the E-clips from the shaft which pushes the shift fork into place, and push the shift fork all the way into the engaged position, then reinstall the e-clips behind the shift fork. (it works I have done this on the trail when my old vac actuator gave up)
much better than having a foreign object (hose clamp) in there to possibly damage seals
much better than having a foreign object (hose clamp) in there to possibly damage seals
#15
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a "better" way of doing this is to remove the E-clips from the shaft which pushes the shift fork into place, and push the shift fork all the way into the engaged position, then reinstall the e-clips behind the shift fork. (it works I have done this on the trail when my old vac actuator gave up)
much better than having a foreign object (hose clamp) in there to possibly damage seals
much better than having a foreign object (hose clamp) in there to possibly damage seals