Clutch Mod Question
 

Hey,
Long time lurker, first time poster here. 2012 JK Rubicon 137K miles. 6 Speed manual. Zero Mods (yet). Mostly highway miles. Never off road. I’m moving to St Thomas USVI in the next few months. Clutch is original, no issues. St Thomas is a very mountainous island with very steep and not so great roads. Some roads are so steep/bad that 4x4 must be used for short periods (1/2 mile at most) on dry surfaces. Thinking it’s best I replace the clutch before I go just because I have the luck that it will fail as soon as I get there and be super expensive to fix on island. Thinking of a heavy duty clutch but have no idea where to start my research. Any advice would be greatly appreciated. This may not be a permanent move so a clutch that will also possibly work on US roads as well would be ideal. Thanks in advance

There's nothing wrong with a factory clutch. LuK makes good clutches as well (OEM provider for some). Sachs makes your factory clutch, so that likely wouldn't fall into "heavy duty" but works. I'm using a Spec stage 1 (or 1+), and it's not bad. It grabs faster/ harder than the factory one did. It doesn't like a ton of activation though (stop and go traffic) but does great off-road. It just gets super touchy in heavy traffic. I think I'm at 100k on this clutch after putting 120k on the factory clutch. Both have been off-road, seen traffic, pulled trailers heavier than they should have, and run larger tires.

By coincidence, my next clutch is on the Fedex truck for delivery today. Trying a centerforce II this time, and my plan is to remove the centrifugal weights to lessen the pedal pressure at higher RPM's. Also going with their heavier flywheel because I'm mostly in steep hills, and will be towing as well. This flywheel has a sealed ball bearing rather than the usual roller type pilot bearing which I think will be better, less likely to have grease contaminate the clutch. This obviously isn't a recommendation yet, but what I would recommend is replacing the clutch fork, trans input shaft tube (that the release bearing slides on) and pivot ball along with the clutch + release bearing. The flywheel can be block sanded if it just has normal wear, rather than replaced.
:cheers:

Removing the centrifugal weights can let the clutch slip a little at the higher rpm where the torque builds higher. They are designed to grab more at those higher rpms

I emailed Centerforce a while ago and the weights contribute to about 10% of the rated torque capacity. This CF2 clutch is rated at 458 lbs-ft, so 458 x .9 = 412 lbs-ft without centrifugal weights. The engine puts out 240 lbs-ft @ 4000 rpm. 412 / 240 = 1.7 , which sounds like a decent safety factor. No plans for forced induction, so it looks good to me. Hate to do it, but my left leg has seen better days.
:cheers:

Honestly, the real failure point is the throwout bearing. 268,000 miles on my '07 and never had the clutch itself fail. But have had a couple TOBs that needed replacing, so just did the clutch at the same time. Been running the Centerforce Dual-friction clutch for the past 170,000 miles and do like it. It has a lighter pedal than the OEM clutch. Which works well now that I drive both the JK and a JT, which also has a similarly lighter pedal than the OEM JK clutch. Now, if I could only burn into my brain that reverse gear is on opposite sides of the shift pattern for each of those!

Anyway, back on your question: Yeah, I'd rebuild the clutch in your situation. But wouldn't worry about heavy duty parts. Probably should also replace the rear main seal and maybe even the front seal on the transmission.

I put the center force on when my first clutch went out. It did not last any longer than the factory one. I also made the mistake of putting on the heavy fly wheel. On my next clutch it will be coming off. The extra weight was not worth the performance gain. Price is also stupid on the center force. Currently running a LuK.

Get what you're saying about the heavy flywheel. Your Jeep has a lot more rotating mass than mine in other places, and it all adds up. I'm in a mood to experiment a bit...

:cheers: