Pearl: The Unicorn XJ

[Buddy_Holly]

Nice seeing you posting again. Always enjoyed your build. And your rebuilds  [laugh]

Don?t call it a comeback 😀

 

[G Beasley]

Don?t call it a comeback 😀

LLucas?

 

[Buddy_Holly]

Housing is blasted, headed to Beasley?s tomorrow to get the truss fitted and weld everything up. Ring and pinion are deburred and waiting on REM treatment. Getting close!

 

[G Beasley]

Jeebus that?s clean , but by the end of tomorrow it will have Lucas prints all over it.

 

[Buddy_Holly]

Truss, LCA brackets, and gussets are welded on. Time to throw the bar in it tomorrow to confirm it hasn?t moved and then off for final blast and powder coat.

 

[G Beasley]

Looks good, time to get this pig squared up!

 

[Buddy_Holly]

Antirock and rear sway bar are on. Had to whip up some drop brackets for the front and modify the stock stuff to weld to the u bolt plates in the rear.

New metalcloak double adjustable uppers, and converted the JJ lowers to duroflex joints. Also welded the track bar bracket to the frame. Drives much better now! So much better that I had time to buff and wax the ole girl. This is likely the first wash since I was in Moab two years ago.

 

[Buddy_Holly]

And the subsequent clearance test:

 

[Buddy_Holly]

Housing is powder coated! Waiting on ring and pinion to get REM polished and then I can work on assembling.

 

[RokAddict85]

For those out of the loop, what is REM?  Jeep and axle work looks great!  Super clean. 

 

[Buddy_Holly]

For those out of the loop, what is REM?  Jeep and axle work looks great!  Super clean. 

So REM is a chemical superfinishing process thats very popular with racers. REM is actually the brand but it?s like calling a tissue Kleenex. There are a few others that do superfinishing. Some also add a coating to help retain oil film. MicroBlue is one that comes to mind that polishes and adds some sort of coating. Parts are put in a tumbler with certain chemical solutions and media and it micropolishes the part, creating a chrome-like finish that?s super smooth. It cuts down on friction and allows the oil to do a better job, thus reducing temperatures. It?s very slight, but it can also cut down on parasitic drivetrain loss which is why racers REM polish everything they can. It?s absolutely unnecessary for a jeep but I may as well do it since I can toss my gears in with the next batch of gears we do for a race team. I?ll get pics when this one is done to show what it looks like after it?s been polished. It?s pretty cool looking.

In addition, we also typically deburr every ring and pinion we do so I went ahead and did that as well. Pretty much means any square edge you see gets chamfered with a die grinder and sandpaper wheel. Supposed to help prevent cracks from forming under high stress.

An extra step in this process would be to get the gears cryogenically treated but nobody local here does them anymore. Cryo treating essentially freezes the parts to some absurdly low temperature which alters the metallurgical composition and strengthens the gears.  Think of it as a form of heat treatment, except with the opposite of heat. The surface of the gears are also slightly harder which means less prone to wear after having this done.

Is any of this worth it for a D30? Probably not [laugh]

 

[RokAddict85]

Very cool, thanks for the info.  It seems worth it from a longevity standpoint since you have access to do it.  Do you know how you bent the C?  In the pre-jk/jl era there was a lot more talk on cryo treating gears, but it seems with so many axle swap options less and less people bother.

 

[G Beasley]

Housing looks good , get up here and finish it!

 

[Buddy_Holly]

Very cool, thanks for the info.  It seems worth it from a longevity standpoint since you have access to do it.  Do you know how you bent the C?  In the pre-jk/jl era there was a lot more talk on cryo treating gears, but it seems with so many axle swap options less and less people bother.

It may have been from an accident before I got it, or it may have been from when I jumped it at Rausch Creek a few years ago [laugh]

 

[badmonkey]

Moater we're maished? 😀

 

[Buddy_Holly]

Ring and pinion are done! The lighting in the shop makes it hard to show accurately. It looks like chrome. In the second picture you can kinda see the deburr job on the ring gear teeth.

 

[G Beasley]

No dirty thirty here ?

 

[Buddy_Holly]

Progress! Gears are mostly installed and done. Have to swap the setup bearings for normal ones and confirm carrier preload is good. Then onto getting the housing dressed and ready for install! Ring and pinion are really sharp looking. Shame that nobody will ever see them.



Re-used the pinion shim from this housing with the old 3.07 gears and it looks like depth is spot on. Both my 4.10s and the original 3.07s in this housing were a +2. What?s wild is the pinion shim still was very different between the two gears. The 3.07 had a .027? thicker shim, which means the housings were quite different as far as the pinion machining goes. Backlash is pretty tight, on the lower limit. This would be too tight for something I would normally do, but the gear is used and the rem polish makes it so slick it would be hard to burn a gear up in normal use. This is more of an aggressive setup than most street vehicles normally run. Under hard loads it will be perfect.

Drive side:



Coast:



For anyone wanting a great tech video on pattern reading and manipulation, Carl Jantz did a great one and I still watch it every time I do a gear install.

https://youtu.be/nVb5WRUfM7Y

 

[Buddy_Holly]

It begins.

 

[G Beasley]

Chop chop! Killer little Dana 30 , very impressed with your work so far.