Michigan 2018 Sport Unlimited JL - Moderate Budget - Maximizing Wheeling

[bllprk]

So what is still wrong with my JL?

1. Gearing is too tall.
2. I don't have lockers
3. I only have 35's

Option 1: Buy rubi take offs. It gives me two lockers. It makes my gearing better. And maybe later I could run 37's. Problem is, there are few available right now. Prices are high, and even after paying the price, I would only have 4.10's, which are still too tall for what I would prefer.

Option 2: Re-gear. Professional re-gear ($2400) and a Eaton Locker ($1400). Good option. BUT, a lot to invest in a Dana 30, which may decide to grenade.

Option 3: Re-gear myself, with open box gearing parts. Super cheap, discounted price. If I really mess up the gearing, or grenade my D30 then I am only out time and a few hundred bucks.

So, as of right now, Option 3 it is... BUT what size gear? I think the ideal set is 4.88's with 35's and a manual trans. 100 crawl ratio! BUT I found some 5.13's for pretty much half off. So, the goal is 5.13's.

Below is an image of the D44 verses D30 ring and pinion. I can see why people don't love the D30.

So, here is my commitment to the community. I am going to run a dana 30, with 35's, and 5.13's and see if they break.

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[bllprk]

Another project... can I tow my jeep with my other jeep? The answer is, yes its possible, but it does not feel safe enough for me.

The GC is a 3.0 CRD.

Edit: The plan is to flat tow the black jeep with the red one. Details to come soon.

 

[bllprk]

Got a new bumper. Had to test it out. Open box deals at Extremeterrain.

 

[DEdney1775]

Great build!! I'll be following! I'm originally from Moline, Michigan. I've always wanted to go wheeling @ Drummond Island.

Here to see how the D30 holds up!

 

[TylerV76]

Great build thread! Love to see what the sport axles are actually capable of.

 

[bllprk]

Gears are in! What a project. Thanks to @chevymitchell for all his write ups and videos. I studied them like a hawk. Amazingly helpful.

2018 Sport. Dana 30 / Dana 44.
I went with 5.13's because I got a good deal.
When I dis-assembled the rear, I found the oil slinging spider gear washer was failing. Chunks of metal in the diff. My fastest option was finding a Trac-Lok at a local dealer.

A friend allowed me use of his garage / lift / heated. This was very nice.

Revolution Gears and Master Install Kits

Some notes / observations:

• Time
  • It took me 27 hours to do the job. That includes about 7 hours due to finding the new part due to the broken oil slinger shim.
  • I had help, who contributed about 15 hours.
  • We wasted at least a few hours making a setup bearing, and pipes to help press bearings.
  • Front axle build took significantly more time than the back.
• Gears / Pattern
  • Heating the ring worked perfect. It dropped right now.
  • The D30 pinion shims were under the bearing. The Revolution gear did not have a little step under the head. We did make a fit bearing. Without that, I don't think a bearing puller would have worked.
  • The factory shims, almost produced a good pattern right away.
  • D30- factory pinion was spot on. Had to adjust backlash quite a bit.
  • D44- factor pinion was about .003 shallow. Then adjusted backlash.
  • D44 - had no carrier pre-load (from factory). It just fell out.
  • All factory shims were a single shim. There were no packs.
  • The Master Install Kits, did NOT have enough shims and enough combinations. Especially on the D44. The D30 was good but uses the same shim on both sides of the carrier allowing for more shim combinations. I was limited on adjusting the pattern due to shims on the D44.
  • The D44 Pinion Shims were under the outer race / housing. That worked pretty well for pinion depth changes.
  • The D44 axle shafts were hard to get out. Using the disc, it took a lot of beating to get them to slide out (63,000miles on the jeep)
  • My D30 pattern looked very good. My D44 pattern just looked good.
  • Crush Sleeve on D30 was terrible. Massive breaker bar. Painful
  • Crush sleeve on D44 worked with impact.
• Results
  • I went from 3.45 to 5.13
  • I am running 35's (Cooper SST Pro)
  • 1st gear with the 3.45 required much feathering, and required a higher RPM before shifting to 2nd. If you shifted too soon, then you would bog and have no power. The high way, 4th gear was king. 5th maybe at 75mph, until you hit an incline. 6th is nope.
  • With the 5.13's. First gear is short. 0-17mph. I can skip first and just start up in 2nd just fine. 70mph, in 6th gear is 2500rpm. (a little taller would be nice) Merging onto the highway was amazing.
  • I am most excited about the crawl ratio:
    • Factory for sport is 48
    • Swap the t-case with a rubi is 71
    • Adding in 5.13's is 105
  • I can't hear the gears. (I do have some tire noise)

Hard to say if I would try that again. I learned a lot. I had a great time. I saved some money. But it was hard.


5.13 next to 3.45

Broken washer on D44 (open diff)

D30 and D44 Rings

D30 and D44 Sets

D30 and D44 Pinion

 

[Mudduck]

Awesome!

 

[bllprk]

Great build!! I'll be following! I'm originally from Moline, Michigan. I've always wanted to go wheeling @ Drummond Island.

Here to see how the D30 holds up!

I am breaking it in currently. We have Moab in June, Drummond Island in August, but I am going to have to fully test it before June. I need to get 500 miles on this ASAP!

 

[bllprk]

Did some testing. The crawl ratio is at 105:1. In 4 Low with a rubicon TC. This video shows the crawl speed. No clutch, no brake, and no gas. Just crawling. I did use some gas at one point to kick in the limited slip.

I am very pleased. It just walks. Even when you start the engine, I can use the brake and clutch to start moving. No gas needed.

 

[bllprk]

Attempted towing my Wrangler with my Jeep Grand Cherokee. Ended up being a fail. I think the weight differential was too little. Steering to the left or the right causes a chain reaction. Jerkiness. Wet and curvy roads felt like it would be easy to jackknife.

Setup:
Blue OX Towbar with adapter for D-rings on my bumper.
NSA RV Brake
TOAD Taillight Wiring thru Jeep

 

[bllprk]

Rival Gas Tank Skid... Went with Rival aluminum due to my less concern with a gas tank skid, the low price, and the light weight nature of aluminum. Looks good. Setup pretty good. Lost clearance.

https://www.rival4x4usa.com/collections/jeep-wrangler-jl

I am using this skid with the Rough Country steel set for transmission and engine.

 

[bllprk]

Did my 500 mile gear fluid replacement and inspection. Grey fluid. Everything was tight. Backlash was good. Hopefully this pattern is still good? No clue. I think its great.

 

[bllprk]

Purchased a Centerforce clutch. This is going in soon. Got it open box at Extremeterrain. Its heavy. Hoping to do a rear main seal at the same time as this.

 

[bllprk]

Install started. Found an oil leak either on the rear main seal or the upper oil pan. Corrected it.

 

[bllprk]

Centerforce Clutch - Self Install Review

Jeep Details:
Jeep Sport 2018 3.6L 6Speed Manual Transmission. 2 inch lift. 35" tires. M186 / M220 5.13 Gears. Rubicon Transfer Case. Open Front / LSD Rear. Crawl Ratio of 104:1 65,000 miles

Background:
I go off-roading as much as I can. I try the hard stuff. But remember, I drive a Sport on 35's.

Stock Clutch: I didn't mind it. I like the light clutch pedal. I did burn it up a few times off roading. I went to a crawl ratio of 104:1 to help avoid that. Maybe it would very slightly slip at 5k rpm on heavy acceleration. I replaced the stock clutch because I didn't want it slipping and exploding on a trip to Moab. I was also excited to get the heavy flywheel. I did NOT love the stock flywheel. This jeep was so easy to stall. The other note is the clutch was very on or off in terms of engagement. It didn't really feather.

Install:
Centerforce ® II, Clutch and Flywheel Kit Item #: KCFT157077. I installed this myself. Total install time was about 11 hours and that included changing the rear main seal. I also had to remove and re-install skid plates. Install was straight forward. Pain points included the top fasteners on the bell housing and the bracket. I did separate the transfer case. I did not disconnect the shifter linkage. I had tons of room to put the transmission to the side. I installed this on the floor of my garage.

With respect to mounting the flywheel: use one of the old flywheel bolts and cut the head off. Use that to hold the flywheel in place (and while trying to align the holes). I also purchased 2 long bolts and cut the heads off to align the bell housing to the engine. With respect to bleeding the clutch, follow Centerforces instructions exactly. It was a very straightforward install. I have only installed one other clutch in a TJ.

Performance:
My first comment is that the clutch feels like a clutch. It engages smoothly, pedal force is a bit higher (to push down the pedal) than stock, but it feels like a traditional single disc clutch.

This clutch feels right. Right now I am trying to teach my son a manual transmission. On the factory clutch, he could never feel it engaging. Even with the 5.13's he still struggled with stalling. He loves this new one because he can tell when it's starting to grab.

I have 600 miles on it now. I did some simple off-roading obstacles at a friend's house. First thing to note wasn't I didn't stall a single time. I have one video of the engine running very low RPM due to me being on the brake, and while it was lugging, it kept going. The other thing I noticed was I could actually control speed with the clutch itself. I could let it slip a bit, and it performed beautifully. While rock crawling, with my crawl ratio and the Centerforce clutch, I don't need the accelerator at all. I know not to slip the clutch while driving. But, it's nice to know that on the hardest obstacles, I have an additional tool to get up it. Jeeping with the Mopar twin disc clutch, I had forgotten you could do this with a clutch.

I will be disabling the ESS at some point. I just want to save the wear and tear on the starter due to the heavier flywheel.

I did run into some questions about bleeding the hydraulics. Centerforce was on the phone with me almost immediately to help me work through the issue. The support was top notch.

So, in conclusion, I am happy to have the risk of a Jeep fire removed. In addition, I gained some amazing off-road capability. Very happy to have a solid flywheel and a single disc clutch!

Video of me not stalling...

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