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front axle swap- d30-suggestions?

bcmaxx

NAXJA Forum User
Hi I currently have an 89 xj with a non disconnect d30 with 3:55, I just got a complete d30 disconnect axle with 4:10's to swap in (out of a 88 xj). Just a few questions:
-Is there anything I can strengthen up as I was told they are not as strong as the non disco? I will be beefing up the upper control arm mounts.
-I have heard of people welding there spiders and using the disconnect on the highway. Good idea or bad? I am a weekend wheeler in the rockies.
-I am planning on installing precision double strength u-joints, anything better out there?Some people say buy oem from the dealer.
-Anything else that might help me out Thanks All!!:guitar:
 
The passenger side UCA mount is way stronger on the disconnect axle. One problem(weak link)with the disco D30's, is they use smaller axle u-joints. An upgrade to latter model one piece axles results in a stronger assembly(larger u-joint and one piece), but you loose the disco feature. Search this forum RE D30.
 
I only have one question left- can I weld the spiders and still highway drive and weekend wheel? Thanks
 
Don't weld the spiders unless you have lock-out hubs on the front. You are not an idiot for wanting to be locked. Lock rights are cheap.
 
There are people who have welded the spiders and use the disconnect....be aware....the driver side axle will always be locked and the driveshaft will always run...no problem??? the original axle is a non-disco??? With the passenger side axle discoed....on the highway it can get a bit squirrely..the drive side will have drag and the pass side will not....could tend to pull left unexpectedly....And here is another fact...the disco will be more difficult to engage...and even more difficult to disengage with the diff welded...stock disco axles unlock easily because of the spider gears and the front shaft being freerunning in high or neutral....if you have the axle in a bind of any kind, the vacuum wont pull it out of engagement...and if you get a pull cable, you will break the cable or shift fork trying to disengage it under any bind...

If what you are after is the better gear ratio...4.10 is not a lot better...you don't say what size tires you run, or plan to run...if over 30...you need more gear anyways...never mind the mall crawler opinions...If you are after strenght, the disco Housing is stronger...but the U-joints are small and the inner shaft is prone to breaking under heavy load...

I faced the same questions...I used a nondisco....(a nondisco with ABS HAS the 297 U-joints)...braced the pass side CA mount and added a truss...tossed in a Aussie....good to go...
 
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If all you're after is the gears I think you could take the 4.10 ring and pinion and have someone put it in your axle, and at the time, rebuild it, if it hasnt been rebuilt lately.
 
I never thought about the binding and inability to easily lock unlock the disconnect, I am going 33's I currently have 31'a with 3:55 which arent bad right now, I have already got these 4:10's laying in my garage so I'm keeping them. I can't afford better right now I just dumped $1200cnd into a shortblock.
 
If you are going to 33's...you need at LEAST 4.56....preferably 4.88....
 
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