Arizona Rock Crawler

Nope what is that?
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Might not be your preference but it makes the shifter much easier to get to and use off road. The factory handle is low for legal/idiot reasons. You can put whatever knob you want on it.
 
This will be a story about vibes... So I’ve always had a vibration in my Jeep at 70mph since the day I got it. When I first got it I got my front driveshaft balanced and rebuilt. This helped the vibes become tolerable but still present. Fast forward a year to present day. I want a tummy tuck. I install tummy tuck. PO already had adjustable arms on. I measure front driveshaft at 7.5 degrees with my non digital angle finder. Set pinion to 7.5. Drives perfect up to 65 and still get that vibe. But this time it’s a little worse. I pull the driveshaft and vibes completely gone. It couldn’t be my angle because they were both equal and opposite 7.5 degrees. I go through all possibilities. I’m determined to get rid of this vibe and have a perfect ride. Well turns out the spot I was measuring on my shaft was giving me a different measurement than anywhere else I measured. So I measured further up the shaft and was really getting 9 degrees now. Raised my pinion up to 9.5 and almost entirely vibe free now. My pinion must have always been low relative to the shaft even before the tuck. I Will get a digital angle finder today and make sure everything is precise. I don’t really trust my needle one anymore.
Moral of the story is to measure all the way up the shaft tube to make sure you are getting the correct and consistent angle and use a digital finder. So happy to be vibe free now for the first time ever!
 
This will be a story about vibes... So I’ve always had a vibration in my Jeep at 70mph since the day I got it. When I first got it I got my front driveshaft balanced and rebuilt. This helped the vibes become tolerable but still present. Fast forward a year to present day. I want a tummy tuck. I install tummy tuck. PO already had adjustable arms on. I measure front driveshaft at 7.5 degrees with my non digital angle finder. Set pinion to 7.5. Drives perfect up to 65 and still get that vibe. But this time it’s a little worse. I pull the driveshaft and vibes completely gone. It couldn’t be my angle because they were both equal and opposite 7.5 degrees. I go through all possibilities. I’m determined to get rid of this vibe and have a perfect ride. Well turns out the spot I was measuring on my shaft was giving me a different measurement than anywhere else I measured. So I measured further up the shaft and was really getting 9 degrees now. Raised my pinion up to 9.5 and almost entirely vibe free now. My pinion must have always been low relative to the shaft even before the tuck. I Will get a digital angle finder today and make sure everything is precise. I don’t really trust my needle one anymore.
Moral of the story is to measure all the way up the shaft tube to make sure you are getting the correct and consistent angle and use a digital finder. So happy to be vibe free now for the first time ever!
Awesome news!
 
Awesome news!
I just got off the phone with Tom woods and wow do they have the best customer service on the planet. They explained everything I wanted to know in maximal detail even though I wasn’t ordering anything. I told them about how tilting my pinion up decreased my front driveshaft vibes. And their answer was super interesting And great info for everyone to know. First off they said you actually don’t want to run a u joint at 0 degrees. You want about a 1 degree difference between differential angle and driveshaft angle. So I’m at 9.5 at the front diff and 8.5 at the shaft. This is perfect.

Here’s the interesting part though especially for people who deal with vibes. They said the geometry correction I did isn’t what fixed my vibes. That subtle geometry correction would fix vibes for a Driveshaft under load, which the front shaft is not while in 2WD. What fixed the vibes was actually that tilting the pinion up actually pushed the slip joint further in and put the slip joint in a better more stable position that the shaft likes better at high speeds. He emphasized the difference between vibes you get from a driveshaft that’s under load and how that is what is effected by geometry whereas a passive but spinning driveshaft vibe is effect more by its balance and the position of the slip joint.

Key takeaways are:
You don’t want your ujoint at 0 degrees. You want a degree of difference. Ideal Pinion angles are 1 degree lower in rear and 1 degree higher in front.

Geometry change is how you fix a driveshaft vibration UNDER LOAD.

Balance and position of the slip joint is how to correct vibrations from a spinning driveshaft NOT under load.
 
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Did my final button up today and finalized all the little details like last pinion angle tweaks and an alignment and a little more trimming I had to do on the skid for driveshaft droop. I am DONE. Tummy is tucked and since I went through and adjusted everything on the Jeep it drives better than ever. Vibes are gone and every detail is accounted for. Shoutout to @Midnight LJR and @mrblaine for motivating me to stay patient, and do things right. I can’t tell you how many times I got frustrated because had to completely redo something to get it it perfect but it was so worth it.

I’m dying to go offroad but after driving in my Jeep my dad wants me to go through his Jeep tomorrow and set his up perfect as well. He is experiencing some weird vibes that I will have to spend some more time diagnosing.
 
Did my final button up today and finalized all the little details like last pinion angle tweaks and an alignment and a little more trimming I had to do on the skid for driveshaft droop. I am DONE. Tummy is tucked and since I went through and adjusted everything on the Jeep it drives better than ever. Vibes are gone and every detail is accounted for. Shoutout to @Midnight LJR and @mrblaine for motivating me to stay patient, and do things right. I can’t tell you how many times I got frustrated because had to completely redo something to get it it perfect but it was so worth it.

I’m dying to go offroad but after driving in my Jeep my dad wants me to go through his Jeep tomorrow and set his up perfect as well. He is experiencing some weird vibes that I will have to spend some more time diagnosing.
Like I said, my main skill is perseverance and patience as you've discovered. Nice work.
 
Did my final button up today and finalized all the little details like last pinion angle tweaks and an alignment and a little more trimming I had to do on the skid for driveshaft droop. I am DONE. Tummy is tucked and since I went through and adjusted everything on the Jeep it drives better than ever. Vibes are gone and every detail is accounted for. Shoutout to @Midnight LJR and @mrblaine for motivating me to stay patient, and do things right. I can’t tell you how many times I got frustrated because had to completely redo something to get it it perfect but it was so worth it.

I’m dying to go offroad but after driving in my Jeep my dad wants me to go through his Jeep tomorrow and set his up perfect as well. He is experiencing some weird vibes that I will have to spend some more time diagnosing.

Good job!
 
You know something is wrong when your dad sits in your Jeep (which has a lopro Mount) and he says how smooth the idle is. Dropped his jeeps skid and found this!
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bushings just fell right out. No wonder his Jeep felt rough 😂 Good thing I have a spare now that I just put in my lopro!
 
Wow, that mount is toast! You've given me new hope that with a little more fine tuning, I might be able to fix my vibes. My front DS is 1.3* lower, and my rear DS is at 0*.
I might even consider doing some measuring to see what range the DS needs and have a custom length made to get better spline engagement.
 
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Wow, that mount is toast! You've given me new hope that with a little more fine tuning, I might be able to fix my vibes. My front DS is 1.3* lower, and my rear DS is at 0*.
I might even consider doing some measuring to see what range the DS needs and have a custom length made to get better spline engagement.
Nice yeah see what they say about your spline engagement. Do you have an aftermarket front DS? Mine vibed at 1* low and vibes went away at 1* high. Driving in the wind today definitely could feel the loss of caster a little bit but probably to be expected at a 9.2* pinion angle. I may end up getting a tom woods front at some point and seeing if I can run the pinion a little lower with it and still be smooth but will have to recover my pocket a little after this tuck.
 
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I've been thru 2 new Adams front shafts, and am on my 3rd Adams rear shaft in 3 years. I went so far as to send my front DS to Tom Woods to have them check it out. They balanced it a bit better and sent me new yokes for the t-case to try out. I have replaced all the yokes now. I have a Barnes 1" raised t-case skid. I'll try moving the front pinion angle up 1.5* and lower the rear 0.5*, but I've been down this road, so I'm not hopeful.
 
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Well we put my old tranny mount in my dads Jeep and it drove good as new. He was so happy! Next I need to cycle his suspension and get that all dialed in for him. Once my dads Jeep is dialed in we are hoping to drive down your way @bobthetj03 and conquer the Rubicon at some point. He wants to do some 4.88 gears and a rear locker first though. Already locked in front
 
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I've been thru 2 new Adams front shafts, and am on my 3rd Adams rear shaft in 3 years. I went so far as to send my front DS to Tom Woods to have them check it out. They balanced it a bit better and sent me new yokes for the t-case to try out. I have replaced all the yokes now. I have a Barnes 1" raised t-case skid. I'll try moving the front pinion angle up 1.5* and lower the rear 0.5*, but I've been down this road, so I'm not hopeful.
Sheesh. And no vibes when you take off the front shaft?