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Dana 30 Build: Sleeve, Truss etc.... for 35's

Dynatrac Pro Rock 44 or rockclimbers 30. Hrmm. ;)

Hopefully someone learns from his mistake.


That axle didn't even exist when my 30 was built. The components that went into it were the top of the line at the time.

And guess what... This Dana 30 has survived 2 jeeps both on 35" Tires with well over 150k miles on it. I have broken 2 things in the nearly 15 years this thing has been built, both the result of being stupid.
 
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Have enjoyed this tread and read it completely considering a upgrade to mine.

After 2 yrs. on a stock D30 with a Detroit Locker and 4.56 gear on 33" tires have not not had any issues so far. Most of my use are fire trails (marked impassible due to flooding washing out most all yrs. ago.), mountains (Ozarks), some rocks and off road parks with all levels of trails. I stay off the most difficult trails in the parks my ability not the XJ's.

Have decided to keep what I have till something breaks then build a spare D30 in a another XJ that I bought a year ago, a parts XJ. Have other went this route also, waiting that is till you deem it necessary?
 
If it ain't broke don't fix it. But if you feel the need to build a stout Dana 30 why wait if you have the spare housing? What if your current one never breaks? Will you be going bigger tires and wheeling harder trails? All things to think about.
 
Made a little progress Saturday and Sunday..

Off topic RE D30 but its my thread right?

Cross Member


Details of skid plate for bolts that hold the transmission mount. I cut out the studs and added nut plates that are welded to the mount. I made a spare to carry with me since its a custom item.



Installed looking from frame rail to frame rail. FLUSH.



View looking up from underneath



Of course the price you pay for all this is a big cut out in the trans tunnel. The transfer case has an inch clearance on top and off to the side it will have 2-3 inches under the cover that I have to fab up. The driver seat has to be moved back 3 inches for the seat frame to clear but the seat itself is no problem.



Framing in the cut out. 1x1/8th metal with rosette welds. Two will be placed side by side and then joined. This way the inner strap can "flare upward" or have a different curvature to follow the tunnel giving a lot more strength since it adds section thickness. The cuts in the sheet metal were welded up prior to putting this in. A strip of copper strap under the sheet metal joint made welding up the cuts in the sheet metal, including filling in the gaps a breeze.



John
 
If it ain't broke don't fix it. But if you feel the need to build a stout Dana 30 why wait if you have the spare housing? What if your current one never breaks? Will you be going bigger tires and wheeling harder trails? All things to think about.

Bigger tires and harder trails. Up to 35's from 31's. East coast guys will know the trails...stepping it up trails. Corum Special at the Cove is the max I can do on 31's (run it 3 times 4 hours, 2 hours, 45 minutes the last time on AT's). There are two I absolutely can not run on 31's, Rock Creek at Rausch Creek in Pa and Pennsyltuckian at the Cove in WVa. Both really do require 35's. Rock Creek is huge boulder field about 1/2 mile long, smooth granite bolders 3-5 feet with huge holes (6 feet deep) and lots of "smaller rocks" pointing up everywhere. Its a minefield. Drove it in a LJ on 40's (nicely built) and it was too easy. I think 35's will be sweet spot for keeping it difficult but not impossible. Pennsyltuckian is on a hillside (go up or down) with boulders the size of washing machines, another glacier generated rock fall.
 
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that is a very nice X member dude. Makes me want to rethink mine and copy yours and BS fabs. Did you clock the 30 at all or just leave factory position and still have to cut the floor to fit it flush with the frame?
 
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OH DID I EVER CLOCK IT. If you read the BS Fab thread on suspension build you will see that the drive shaft hit the long arm just a few inches forward of the cross member. If you look closely at the picture below you will see that the new holes in the AW4 extension housing are directly under the square casting recess. This is about TWICE as far away "around" from the stock holes as the one that BS Fab drilled. This rotated the transfer case twice a much, an extra inch an a half, maybe 2 inches up at the front yoke. Now I have not put the long arms in and I have not installed the shaft but I am pretty sure I wont have the same problem that BS Fab had. They only had to drop their cross member 3/4 of an inch to get the clearance back.



The transmission mount is only about an 1-1/2 inches higher than stock so its the combination of the mount going up and the "extreme" clocking that got the xfer case up into the tunnel. My mount sits on the "floor" of the cross member so its flush with the bottom of the frame rails. If you follow the Nova Jeepers link

http://novajeepers.net/index.php?topic=19484.0

you will see the entire build including the nut plates for the modified transmission mount.
Its a close copy of the BS Fab build other than the clocking, trans mount and my love or rosette welds on the unibody.

EDIT: I used a 2x4 box tube, they used 3x5 which I cant get locally. So I had to notch the sides for trans mount clearance and add doublers to get back the bending strength of the tube.
EDIT #2: I installed a TJ Rubicon 4:1 box (NP241J 4:1 ratio) which is several inches taller than the NP241 which also necessitated the increased clocking and cutting of the tunnel.

John
 
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Without having ever seen a 241J in person: are there any oil starvation issues with clocking it that much? What's it doing to your front pinion angle?
 
I couldn't imagine an oiling issue. The 241 has a great pump and lubrication system in it, far superior to our 231.
 
Thanks for the information! thats rad man.
 
blondejoncherokee,

Thanks for the compliment. WRT the cross member, a bit of it are my own ideas but the basics are from BSFAB. Really just standing on their shoulders and taking it up a couple inches. Same with the front axle. Cal did the original sleeved and trussed D30, I just copied and made what I think are improvements, time will tell.

John
 
Very entertaining and informative thread.

As opposed to beefing up a D30 I'm gonna hold out for a donor 76-79 f150 for it's ford 9" and HP d44.

I have that exact axle set up for a TJ (direct swap to an XJ) sitting in the shop (truss, high steer, parts mike, truss, narrowed etc) but no gears or locker. I picked it up after I started the D30 build and was going to put it in. When I really studied the D44 I realized that the spring perches and shock mounts were very very high giving up a lot of down travel. With 35's I would have less clearance under the tubes & diff of a 44 than I have with 31's on a D30. Of course the worry is the the R&P on the D30. A few west coast and a LOT of east coast guys get away with 35's on built D30 in rocks so I figured I would take the road lesser traveled and try the D30 before going to the D44.

John
 
After reading through this thread a bit and seeing all the bickering, it seems to me I could build 3 Dana 30's with gears and lockers for the price of one custom axle with all the pimpings.

That way if one breaks I can just swap in a new one. I guess...
 
Or just build it correctly and not have to worry about it breaking. I never took it easy on my Jeep and the only thing that ever broke on the 30 was a ring gear from a crappy, rushed gear install.
 
A properly built D30 will come in just under the cost of a decent d44 and well under the cost of a decent d60 at well under the cost. You will be limited but not very much if you stay with 35's.
 
Here is a chassis teaser to go with the axle. New cross member is flush with the bottom of the frame rails and I am raising the exhaust up into the pax area so I can run a flat belly skid from frame rail to frame rail while maintaining the cat.

Framing in the recess, note the webs on some of the framing between the tunnel and the angle that attaches to the floor.



All but the rear most cover welded in place.



Cat and muffler hung and plenty of clearance. At least one inch above the frame rail bottoms and 1-1/2 under the new exhaust tunnel.




John
 
Sessy. Will it force a lot of heat up through the floor though once your belly is bolted on?
 
awesome. I wheel my moderately built 30 pretty hard on low pressure 35's and have never had an issue.
(truss, chromos, 760x's, 4.56 and aussie)
I go most any where my buddies do with there full size front ends
 
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