"Pacing myself" build

She's smooth as glass with the rear drive shaft out, and vibe city with the front shaft out, so I don't see how a front hub kit would solve my vibes. I'm still working on the theory that my operating angles have something to do with it. Why else would the vibes get better when I lower the t-case. That was how I decided to add a MML (Motor Mount Lift). I lowered the t-case skid 1", which gave me the biggest improvement. Why my jeep is so sensitive is beyond me. Your drive shafts think you have a 6"+ lift with your 4" springs and UCF TT, so I just don't get it. Heck, when I first lifted mine many moons ago, I had to lower the skid 3/4", and that was just a 2.5" lift. Add the increased RPM speeds post regear, and I have a recipe for a back massage.
I have it now where I can just hear it a little above 55 mph, and not feel it until 65mph. If I had the soft top on I wouldn't be able to hear it with the added noise level. Hard top seems to amplify it. Maybe I should sell the hard top and get a Bestop twill top and call it solved, lol!

There is something to your theory reg operating angles. Mine vibed with either shaft out in the past. After I did the suspension upgrade, things definitely improved. I was nearly vibe free without front shaft. After rubicrawler, I'm completely vibe free without front shaft. I threw in the towel after that and ordered the hub kit. Whatever changed, I just want to keep it here.

They were supposed to get installed this week but 2 of the cheap steel wheels I ordered came in bent due to shipping damage 🤬

I've been driving without front ds and I've been enjoying it.
 
Screw you JKS! I ain't giving you free advertising! Lol!
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Headed up Bartlett Springs Rd. To High Valley. Lot's of switchbacks and wash board trail. Pleasantly impressed with the JSPEC shocks! We aired down to 15 and disco'd. Shocks did a great job on the small and large events, and made the jeep feel very planted. Even with the sway bar disco'd the sway felt very controlled on the turns. For a $45 shock I'm pleased with their performance. Better than the Rancho's? I'm leaning to yes. I picked the JKS shocks for their travel lengths, which fit well with my 3" lift, and give a good 50/50ish bias. That may have some advantage over the Ranchos, plus my Ranchos are 3 years old with about 30k on them, so I can't say anything bad about them. If you wan't an affordable shock for a 3" lift that will give you a good travel bias, go with the JSPEC shocks and use the 3" lift option for the rear, and the 2" lift option for the front.
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Headed up Bartlett Springs Rd. To High Valley. Lot's of switchbacks and wash board trail. Pleasantly impressed with the JSPEC shocks! We aired down to 15 and disco'd. Shocks did a great job on the small and large events, and made the jeep feel very planted. Even with the sway bar disco'd the sway felt very controlled on the turns. For a $45 shock I'm pleased with their performance. Better than the Rancho's? I'm leaning to yes. I picked the JKS shocks for their travel lengths, which fit well with my 3" lift, and give a good 50/50ish bias. That may have some advantage over the Ranchos, plus my Ranchos are 3 years old with about 30k on them, so I can't say anything bad about them. If you wan't an affordable shock for a 3" lift that will give you a good travel bias, go with the JSPEC shocks and use the 3" lift option for the rear, and the 2" lift option for the front. View attachment 204906
View attachment 204907
View attachment 204909
Softer or harder on small events? (Pot holes and road blemishes)
 
Softer or harder on small events? (Pot holes and road blemishes)
Softer. On the really hard events about the same as the Ranchos. They did a good job of gliding over the wash board stuff. Usually with the wash board sections you get a good rattle felt in the steering wheel and seat. I didn't feel that. What surprised me most was how planted the jeep felt going around some of 90*, 180* switch backs disco'd. Got quite a bit of lean with the Ranchos. I got nowhere near the lean with the JKS shocks, and I was pretty aggressive on some of the turns on purpose. I've been on this same trail not too long ago with the Ranchos. I definitely noticed a difference. I was not expecting that, especially with an equally priced shock. Gotta take it a grain though. New shocks vs. well loved older shocks. I'd be curious to feel if there's a difference with the JSPEC dual rate springs vs. my OME's. I'm pretty happy with the handling so far, so I think I'll run with this for a while.
 
Softer. On the really hard events about the same as the Ranchos. They did a good job of gliding over the wash board stuff. Usually with the wash board sections you get a good rattle felt in the steering wheel and seat. I didn't feel that. What surprised me most was how planted the jeep felt going around some of 90*, 180* switch backs disco'd. Got quite a bit of lean with the Ranchos. I got nowhere near the lean with the JKS shocks, and I was pretty aggressive on some of the turns on purpose. I've been on this same trail not too long ago with the Ranchos. I definitely noticed a difference. I was not expecting that, especially with an equally priced shock. Gotta take it a grain though. New shocks vs. well loved older shocks. I'd be curious to feel if there's a difference with the JSPEC dual rate springs vs. my OME's. I'm pretty happy with the handling so far, so I think I'll run with this for a while.
Thank you for the review! I will keep them on my short list.
 
I believe the JKS jspec shocks are rebranded skyjacker black maxx or one of the other shocks. It has the same compressed and extended length as one of their models. Not a bad price for sure.
 
I believe the JKS jspec shocks are rebranded skyjacker black maxx or one of the other shocks. It has the same compressed and extended length as one of their models. Not a bad price for sure.
Yeah, it was more about finding the right travel length shocks for my particular lift height to give me a close 50/50 travel bias. A 3" lift is a bit of a red headed step child when it comes to shock choices, so for the price, I took a gamble.
 
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Yeah, it was more about finding the right travel length shocks for my particular lift height to give me a close 50/50 travel bias. A 3" lift is a bit of a red headed step child when it comes to shock choices, so for the price, I took a gamble.
Yup exactly, im in the same boat and will probably be trying out the teraflex vss shocks which is diff than the recommended. As long as they ride good and do the job. 👍

Edit: in my research I noticed the jspec, teraflex and quadratec nitros were probably the most ideal for a 3-3.25
 
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@Alex01, do you still have your old 231 t-case? I'm pretty much ready to throw the towel in on this fucking jeep! I've been playing around with lowering the t-case skid 1/4" at a time and readjusting pinion angles. Nothing is helping. I just keep getting varying degrees of harmonic and vibes no matter where I put it. Gonna try one more adjustment, then giving up.
 
I'm for trying another 231 tcase. What if there's something imbalanced in the output shaft?
 
@Alex01, do you still have your old 231 t-case? I'm pretty much ready to throw the towel in on this fucking jeep! I've been playing around with lowering the t-case skid 1/4" at a time and readjusting pinion angles. Nothing is helping. I just keep getting varying degrees of harmonic and vibes no matter where I put it. Gonna try one more adjustment, then giving up.
Sold it a few months back to free up space. @Lonewolf may have his laying around still since his atlas swap.

Have you checked for vibrations with the shafts attached like @psrivats discussed a while back?
 
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