WRITE-UP : JL WRANGLER 2.5" EVO Stage 4 Boost Lift & Control Arms INSTALLATION

[wayoflife]

If you've got a Jeep JL Wrangler and are wanting to install a small lift on it, this installation write-up will show you just how easy it is to do. For our purposes, Cindy and I decided to get an EVO 2.5" Stage 4 Boost Lift or 'coil spacer lift', as it comes complete with 2.5" coil spacers, bump stop extensions, shock relocation brackets, a new pair of rear sway bar links and front brake line extension brackets. Basically, everything you'd need to run a set of 35" tires on a Sport or Sahara or 37" tires on a Rubicon. Being that we are anticipating making more changes in the future, we also decided to get the 8 heavy duty adjustable control arms that are offered as an option as well. With all that said, the instruction you'll find on this write-up will pretty much be the same for most any lift kit of this size and/or type and should still be helpful regardless of which one you get.



Buy the EVO 2.5" Boost Lift here:
https://amzn.to/2JjGglL

What You will get with the EVO Stage 4 Boost Lift

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• (2) 2.5" Front Coil Spacers
• (2) 2.5" Rear Coil Spacers
• (2) Front Bumpstop Extensions
• (2) Rear Bumpstop Extensions
• (2) Front Shock Relocation Brackets
• (2) Rear Shock Relocation Brackets
• (2) Front Brake Line Extension Brackets
• (2) Rear Sway Bar Links
• Installation Hardware

Optional Components

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• (2) Front Adjustable Lower Control Arms
• (2) Front Adjustable Upper Control Arms
• (2) Rear Adjustable Lower Control Arms
• (2) Rear Adjustable Upper Control Arms

What You Will Need

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• 8, 10, 13, 15, 18, 19, 21, 22, 24mm Sockets & Wrenches
• 7/16, 1/2, 9/16, 5/8, 3/4" Sockets & Wrenches
• 1-1/2, 1-7/8" Wrenches
• Large Crescent Wrench
• Ratchet
• Short Ratchet Extension
• Long Ratchet Extension
• Ft. Lb. Torque Wrench
• Vicegrips
• Floor Jack
• Jack Stands
• Pry Bar
• Hand Drill
• Unibit or Metal Drilling Bits
• Cutting Oil
• Trim Pry Tool
• Dykes
• Hammer
• Duct Tape
• Antiseize
• White Lithium Grease


Preparing the Optional EVO Adjustable Control Arms

---

If you purchased any or all the heavy duty adjustable control arms that EVO offers as an options, the following information will help you to set them up and get them ready for installation.

1. To begin, take a control arm and remove the adjustable Johnny Joint from it.


2. Rotate the jam nut down a bit, apply antiseize to the threads and then work it in by rotating the jam up and down through it.




3. Reinstall the Johnny Joint and repeat Steps 1-2 on all the other control arms you got with your kit.


4. The length of the control arms will all need to be set. EVO does provides measurements for this but it should be noted that these are just starting points and addition adjustments may be required. To begin, take the front lower control arms and set them to 24-1/8" measuring from eye to eye (center of bolt hole to center of bolt hole).


5. When the control arm is set to the proper length, both zerk nipples should be pointing in the same direction as can be seen in this photo.


6. With the control arm set, tighten the jam nut by hand just to keep things in place.


7. Being that the front axle has bushings pressed into the upper control arm mounts, the adjustable front upper arms will have forks instead of Johnny Joints. Again, as an initial starting point and measuring from eye to eye, set these arms to 20-1/4". You'll want to make sure that the open end of the fork is facing the same direction as the zerk nipple on the opposite end. Once set, tighten the jam nut by hand for now.


8. Measuring from eye to eye, the adjustable rear lower control arms should be set to 19-3/4". Again, double check to make sure both zerks are pointing the same direction when set and hand tighten the jam nuts for now.


9. Last but not least, set the adjustable rear upper control arms to 17-1/2" measuring from eye to eye. Verify that the zerks are pointing in the same direction and then hand tighten the jam nut.


You're control arms should now all be set and ready to be installed.

Front Installation Instructions

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1. Unless you have a lift, you'll need to start this install by parking your Jeep JL Wrangler on a level ground, apply your parking brake and chock your rear tires.


2. Starting from the front of your JL, use an 18mm socket and wrench to remove the bolt and nut securing your driver side front sway bar links to the lower axle mount.


3. The passenger side front sway bar link is tied into the track bar mount and utilizes a flagged nut to help secure it in place. Because of this, you will just need an 18mm socket to remove the bolt.


4. Using a 21mm socket, a long ratchet extension and a breaker bar or impact wrench, remove the bolt securing the front track bar bolt to the axle.


5. Raise the front end of your JL Wrangler from the axle using a floor jack and then set the frame rails onto 2 jack stands, each placed just behind the transmission skid bar. For our purposes, we have a lift and are racking up our JL Wrangler but as you can see, the arms are still positioned in the same location.




6. Use a 22mm socket to remove the lug nuts securing your front wheels to the axle and then set them aside.


7. Use your floor jack to carefully lift the front axle just enough to help support the weight of it. You do NOT want to raise it to the point where your frame rails lift off the jack stands.


8. Using an 18mm socket and wrench, remove the bolts and nuts securing your shocks to the axle mounts.


9. Use a 10mm socket to remove the bolt securing the brake hard lines to the frame rail.


10. Use a 15mm socket to remove the nut securing the brake hose and speed sensor wiring to the lower control arms.


11. Use a trim pry tool to separate the push tab securing the locker wiring harness to the driver side upper control arm fork.


12. Again, use your trim pry tool to separate the push tab securing the locker wiring harness to the inside of the frame rail.


13. Unplug the front locker wiring harness by squeezing the gray locking tab and pulling straight back.


14. Moving over the passenger side, use a trim pry tool to separate the push tab securing the FAD wiring harness to the passenger side upper control arm fork.


15. Again, use your trim pry tool to separate the push tab securing the FAD wiring harness to the inside of the frame rail.


16. Unplug the FAD wiring harness by squeezing the red locking tab and pulling straight back.


17. Use your trim pry tool once again to separate the push tab securing the FAD wiring harness to the back of the unit.


18. Using your floor jack, slowly lower your front axle making sure that there aren't any wires or components getting hung up. Continue to lower your axle to the point that you can simply slip your coils out from their perches.


19. Remove the upper spring perch rubber isolators by slipping it down and off the bump stop towers. Set them aside for now as they will be reused.


20. If you are installing new heavy duty adjustable control arms, it'll be helpful to support the weight of your front axle with a couple of floor jacks or jack stands as shown here. I should note that this is not required but it will make things easier to work on.


21. Remove the bolt and nut securing the driver side front lower arm to the axle mount using a 21mm socket and 24mm wrench or large crescent wrench. An impact wrench or breaker bar will be required for this job.


22. Again, use a 21mm socket and 24mm wrench or large crescent wrench to remove the bolt and nut securing the driver side front lower arm to the frame mount . An impact wrench or breaker bar will be required for this job.


23. Making sure that the zerk nipples are pointing upward, install your new EVO front lower control arm onto the frame mount using the factory bolt and nut. I should note that the 16mm bolt will make for a tight fit and you'll need to encourage it through by giving it a few taps with a hammer.


24. You will now want to install the EVO front lower control arm onto the axle mount using the factory bolt and nut. Again, it'll be a tight fit and a few taps with a hammer will be needed to help it through.


25. Being that the EVO control arms use Johnny Joints, you can now tighten the bolts to 103 ft. lbs. of torque + an additional 50° but I would still recommend that you do a final torque check once the full weight of your JL is on the ground.




26. Repeat Steps #21-25 on the passenger side of your JL.

27. Moving over to the front upper control arms, use a 10mm socket to remove the 2 bolts securing the heat shields to the frame mount.




28. Using an 18mm socket and wrench, remove the bolt and nut securing the driver side upper control arm fork to the axle mount.


29. Again, using an 18mm socket, remove the bolt and flag nut securing the driver side control arm to the frame mount.


30. Making sure that the zerk nipple is pointing downward and that the bend in the arm matches the factory arm, install your new driver side EVO upper control arm onto the frame mount using the factory bolt and flag nut.


As you can see here, Jeep was nice enough to provide a viewing port in the frame rail to help you get the bolt threaded into the flag nut.


31. Place the EVO upper control arm fork onto the axle mount and secure it in place using the factory bolt and nut. Being that this mount utilizes a bonded rubber bushing, DO NOT tighten this bolt at this time.


32. Being that the EVO arms do use Johnny Joints and that they won't bind, I would recommend that you tighten the frame bolt to 41 ft. lbs. of torque + an additional 185° now. Once your JL is on the ground, it'll be a lot harder to reach this bolt.


33. Using a 10mm socket, reinstall the factory heat shield back onto the frame side upper control arm mount.


34. Using a 1-7/8" wrench or large crescent wrench, tighten your EVO lower control arm jam nut.


35. Using a 1-1/2" wrench or large crescent wrench, tighten your EVO upper control arm jam nut.


36. Repeat Step #27-35 on the passenger side of your JL.

[wayoflife]

38. The EVO 2.5" Boost Lift comes with coil spacers designed specifically to fit on each side your Jeep. The driver side front spacer is for the most part, round in shape but the top has a tab with a hole in it that extends straight out on one side and curves in on the other. See photo below to help identify the proper spacer.


39. Slide the EVO coil spacer up the driver side bump stop tower and then insert one of the provided bolts and washers through the existing hole on your JL's upper spring perch and through the tab on the spacer.


40. It'll take some effort but you will need to install one of the provided washers and nylocks onto the bolt you just slipped through and then secure everything in place using a 7/16" long socket and wrench.


41. Use a pair of dykes to cut off the nubs on the factory rubber isolator.


42. Reinstall the factory rubber isolator onto the bump stop tower and push it all they up to the base of the EVO coil spacer.


43. If your lower spring perch isolator came off with your coil, reinstall it now and make sure it's seated properly.


44. Take one of the front EVO bump stop extensions and slip one of the provided bolts and washers through the countersunk hole.


45. Place the EVO bump stop extension with the bolt and washer installed inside the bottom of your driver side coil as shown.


46. Slip the coil up the bump stop tower and then slide the bottom of it with the EVO bump extension onto the lower spring perch. Make sure that the EVO bump stop extension bolt goes through the existing hole on the center of the perch.


47. Rotate the coil until the base of it is properly indexed with the isolator.


48. Reaching up from the bottom of the spring perch, install one of the provided washers and stovers onto the bolt and then secure everything in place using a 9/16" wrench and socket attached to a short ratchet extension.


49. Repeat Steps #38-48 on the passenger side.

50. The passenger side EVO bump stop extension will be difficult to install due to the fact that it's near impossible to thread a stover onto the bolt. What I would recommend is that you tape the stover onto the open side of 9/16" wrench and use it to help you reach up into the lower spring perch and get it on.


51. Back on the driver side of your JL, you'll need to scoot the strap securing the axle breather hose to the brake hard line bracket up a bit to give it a bit more slack.


52. The brake hard line relocation brackets that EVO provides with the kit are universal and designed to be installed on either side of your JL. Use the factory bolts to secure them of the to the frame rails. A 10mm socket will be needed for this job.


53. Carefully pull the brake hard lines down just enough to get the index pin into the angled hole as shown in this photo and then secure it to the EVO relocation brackets using the bolt, wash and nyloc nut provided. A 7/16" socket and wrench will be needed for this job.


54. If you are installing EVO shock extensions, the front brackets are designed to universal. Starting on the driver side of your JL, place one of the brackets over the inside shock tab on the axle mount and with the closed end pointing outward. Place a provided bolt and washer through the hole on the bottom of the bracket and through the existing hole on the factory shock mount.


55. Thread one of the provided washers and stovers onto the bolt and then, using a 9/16" wrench, socket and ratchet extension, secure everything in place.


56. Place the provided crush sleeve in between the factory shock mount and EVO relocation bracket and then secure the two together using the factory bolt and nut. Use an 18mm socket and wrench to tighten them to 80 ft. lbs. of torque.


57. Use a pair of vice grips to firmly hold the brake hose/speed sensor wiring control arm bracket and then use a unibit to carefully drill out the mounting hole to 1/2". Take your time and be careful to not rip the bracket out of your hand and be mindful of the fact that the bracket will be VERY HOT when finished.


58. Use the bolt and washers provided to secure the driver side shock onto the EVO relocation bracket. Slip the drilled out brake hose/speed sensor wiring bracket onto the end of the bolt and secure it in place using the provided washer and stover.


59. Use a 3/4" socket and wrench to tighten the lower shock bolt and stover to 74 ft. lbs. of torque.


60. Repeat Steps #54-59 on the passenger side of your JL. Again, the EVO shock relocation brackets are universal and so on this side, the bracket will be placed over the outer shock tab as shown.


61. On the driver side of your JL, plug the locker wiring harness back into its socket on the back of the differential.


62. On the passenger side of your JL, plug the wiring harness back into the FAD.


63. Use an 18mm socket to remove both front sway bar links from the sway bar. These can now be discarded as they will not be reused.


64. Install your new wheels and tires. Use a 22mm socket and/or socket key to tighten your lug nuts to 130 ft. lbs. of torque.


65. Use your floor jack to help remove your jack stands and then set your JL back down so that the full weight of it is on the ground. Have a friend turn your steering wheel one way or the other as needed to help get your front track bar joint aligned with the mounting hole on the axle and then secure it in place with the factory bolt and flag nut.


66. Using a 21mm socket, long ratchet extension and torque wrench, tighten the track bar bolt to 52 ft. lbs. of torque + 155°.


67. Using an 18mm socket and wrench, tighten the front upper control arm bolts and nuts at the axle mounts to 41 ft. lbs. of torque + 185°.


68. Using a 21mm socket and 24mm wrench or crescent wrench, tighten the front lower control arm bolts to 103 ft. lbs. of torque + 50°.

[wayoflife]

Rear Installation Instructions

---

1. Just like up front, before you raise your JL and placing it back on jack stands, you'll want to remove a few components while the full weight of it is still on the ground. The first of which is the track bar bolt at the axle and you'll need a 21mm socket and an impact wrench or breaker bar to remove it.


2. Using an 18mm socket and wrench, remove your rear sway bar links from the axle mounts.


3. Using an 18mm socket, remove your rear sway bar links from the sway bar. Set these aside as you will be reinstalling them up front later.


4. You can now raise the rear end of your JL from the axle using a floor jack and then set the frame rails onto 2 jack stands, each placed just in front of the rear lower control arm mounts. For our purposes, we are racking our JL on a lift but as you can see, the arms are still positioned in the same location.




5. As before, use a 22mm socket to remove your lug nuts and set your wheels aside.


6. Use your floor jack to carefully lift the rear axle just enough to help support the weight of it. You do NOT want to raise it to the point where your frame rails lift off the jack stands.


7. Using an 18mm socket and wrench, remove the bolts and nuts securing your shocks to the axle mounts.


8. Unplug the rear locker wiring harness by squeezing the gray locking tab and pulling it out.


9. There are 2 couplers securing your rear locker wiring harness to the threaded end of 2 screw located on the cross member just above the rear axle. You can remove them simply by pulling them off the thread.


10. Using your floor jack, slowly lower your rear axle making sure that there aren't any components or wiring getting hung up. Once low enough, you should be able to pull your coils out with ease.


11. Using a 21mm wrench, socket and impact wrench or breaker bar, remove the bolt and nut securing your JL's driver side rear lower control arm to the axle mount.


12. Again, using a 21mm wrench, socket and impact wrench or breaker bar, remove the bolt and nut securing your JL's driver side rear lower control arm to the frame mount.


13. Making sure that the zerk nipples are pointing upward, install your new EVO rear lower control arm onto the frame mount using the factory bolt and nut.


14. Slip the EVO lower control arm Johnny Joint partially up into the axle mount and then, using a 1-7/8" wrench, tighten the jam nut.


15. Now, push the EVO control arm joint all the way up into the axle mount and secure it in place using the factory bolt and nut.


16. Repeat Steps #11-15 on the passenger side of your JL.

17. Using a 21mm socket and impact wrench or breaker bar, remove the bolt and flag nut securing your JL's driver side rear upper control arm to the axle mount.


18. Being that there isn't as much room to work with, a 21mm socket and a breaker bar will be needed to remove the bolt and flag nut securing your JL's driver side rear upper control arm to the frame mount.


19. Making sure that the zerk nipples are pointing up and that the bend in the arm is going the correct way, loosely install the EVO upper control arm onto the frame mount using just the factory bolt.


20. Feed the flag nut up into the frame rail and thread the bolt into it. If needed, use the viewing port located on the inside of the frame rail to help get things going.




21. Install the EVO upper control arm onto the axle mount and secure it in place using the factory bolt and flag nut.


22. Using a 1-1/2" wrench or large crescent wrench, tighten the EVO upper control arm jam nut.


23. Repeat Steps #17-22 on the passenger side of your JL. NOTE: The gas tank will block your view of the flag nut and this will make it more difficult to install the bolt into it. A tip that will help out is that the flag extending from the frame needs to be positioned in an angle as shown below. It should NOT be parallel to the opening in the frame.


24. Once again, because the EVO control arms use Johnny Joints instead of bonded rubber bushings that would otherwise bind, you can now tighten the lower control arm bolts to 74 ft. lbs. of torque + 50° using a 21mm wrench and socket. I will also do a final torque check of everything once the full weight of the JL is back on the ground.




25. Using a 21mm socket and torque wrench, the EVO upper control arms should also be tightened to 74 ft. lbs. of torque + 65° at this time especially being that the axle mount bolt will be near impossible to get to later.




26. The EVO rear coil spacers are made side specific and each one will only fit in the correct perch. Locate the driver side spacer, hold it up into the upper spring perch and then slip 2 of the provided bolts and washer through the existing holes. Place washers on the protruding bolts and thread on 2 of the provided nylock nuts as shown.


27. Using a 5/8" socket and wrench, tighten the bolts and nuts to secure the coil spacer to the upper spring perch.


28. Repeat Steps #24-27 on the passenger side of your JL.

29. With the factory rubber isolator on top of the coil and indexed accordingly, re-install the driver side coil.


30. Rotate the rubber isolator until the nub on top can be inserted into the hole on the coil spacer.


31. Repeat Steps #29-30 on the passenger side of your JL.

32. Place the EVO rear bump stop extension on top of the axle bump stop plates and position them so that they're angling toward the front of your JL. Then, use the bolts, washers and nylock nuts to secure them to the axle. You will need a couple of 1/2" wrenches for this job but a 13mm wrench can work for one of them as well.


33. Gather the EVO rear sway bar links, bushings and crush sleeves.


34. Apply a bit of white lithium grease onto the bushings.


35. Using a bench vice, press the bushing into the open ends of the EVO sway bar links.


36. Apply some white lithium grease to the crush sleeves.


37. And then again, use a bench vice to press the crush sleeves into the EVO sway bar link bushings.


What the EVO sway bar links should look like once assembled.


38. To being the installation of your EVO rear shock relocation brackets, you will need to first drill out the existing hole located on the lower control arm axle mount to 3/8".


39. Locate the driver side EVO shock relocation bracket, hold it up to the axle side control arm mount and insert one of the provided bolts through the second hole from the top.


40. Using the EVO shock relocation bracket as a template, mark the center of the lowest hole with a center punch.


41. Remove the EVO shock relocation bracket and then drill a 3/8" hole using a metal drilling bit and some cutting oil.


42. Use a piece of duct tape to secure one of the nylock nuts onto the open end of a 9/16" wrench.


43. Slide the wrench between the axle tube and control arm mount and fasten the bolt to the nut using a 9/16" socket.




44. Using the factory bolt and nut, install the EVO rear sway bar link through the sway bar axle mount and the EVO shock relocation bracket. You will need an 18mm socket and wrench for this job.


45. Using the bolt, washer and nut provided, install your new EVO rear sway bar link onto the factory rear sway bar. You will need a 19mm socket and wrench for this job.


46. Using your floor jack to help align the mounting holes on your rear shocks, secure it to the new EVO relocation bracket using the factor hardware. You'll need to use an 18mm socket and wrench to tighten the bolt and nut to 74 ft. lbs. of torque.


47. Unlike the front track bar which has a spherical joint at the frame mount, the rear track bar on a JL has bonded rubber bushings on both ends. Because of this, you will need to loosen the bolt at the frame mount enough so that the track bar can rotate down freely. You will need a 21mm wrench, socket and breaker bar for this job. This bolt and nut will be re-tightened once the full weight of your JL is on the ground.


48. You can now install your new wheels and tires. Use a 22mm socket and/or socket key to tighten your lug nuts to 130 ft. lbs. of torque.


49. Use your floor jack to help remove your jack stands and then set your JL back down so that the full weight of it is on the ground. Then, take your factory rear sway bar links and install them onto your front sway bar using an 18mm socket.


50. Using an 18mm socket and wrench and the factory bolts and nuts, secure the sway bar links to the axle mounts.


51. On the passenger side of your JL, you will only need an 18mm socket to secure your sway bar link to the axle mount being that the nut is flagged.


52. Just like up front, your JL's rear track bar will not line up with the mounting hole on the axle. Have a friend slowly push on the side of your Jeep until the holes line up and you can insert the factory bolt.




53. Using a 21mm socket and torque wrench, tighten the track bar bolt at the axle mount to 125 ft. lbs. of torque.


54. Again, using a 21mm wrench, socket and torque wrench, tighten the track bar bolt at the frame mount to 74 ft. lbs. of torque + 30°.


55. Using a 21mm socket and wrench, give your lower control arm bolts a final check to make sure they are tightened to 74 ft. lbs. of torque + 50°.




56. Using a 21mm socket, give your upper control arm bolts at the frame mount a final check to make sure they are tightened to 74 ft. lbs. of torque + 80° as well.


57. Finally, your steering wheel will be off center due to the fact that your JL has been lifted. It is important that you re-center this as failure to do so will cause your JL's computer to think you are in a slide and it'll activate your ABS system. To correct your steering wheel position, you will need to use a 15mm wrench to loosen the clamp on your drag link.


58. Have a friend sit in the driver seat and watch the steering wheel as you rotate the drag link adjuster. Rotating it downward will turn the steering wheel to the right and upward will turn it to the left. Once your friend lets you know the steering wheel is centered, use a 15mm wrench to tighten the clamp. I should note that it's pretty hard to get the steering wheel centered on the first try and you'll more than likely need to do this a few times before you get it right.


Make sure to double check that all your bolts are tightened to torque spec and be sure to go over all of them again after the first 100 miles. Aside from that, this is what your JL Wrangler will look like once all is said and done. Click on the link below to see more post install photos.


JET Li LIFTED PICS - EVO 2.5" JL Wrangler Boost Stage 4 Lift Kit

I hope you found this installation write-up to be helpful. Please let me know if you have any questions.


Will You Need to get an Alignment?

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Because the JL tie-rod is not connected to the drag link like it used to be on the old TJ Wrangler, there will be no change to your toe setting. Likewise, the track bar on the JL is not adjustable so no adjustment can be made to the very slight shift that your axles will have. Being that the JL has solid axles, no camber adjustments that will need to be made and unless you opted for adjustable control arms like us, no caster adjustments can be made either. In other words, with the exception of re-centering your steering wheel, a front end alignment will be NOT be needed. IF you did install adjustable control arms, additional caster can be set if needed but if you worked off the settings provided by EVO, I doubt you'll feel the need for it.

Post Install Info

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After doing an initial flex test, Cindy and I found that you will have some rubbing of the rear fender liner and it will need to be addressed. To see full details of our test and our fix, simply click on this link:

FLEX TEST : Will 37's Clear a JL Rubicon running 2.5" of Lift & Without Rubbing??

[OverlanderJL]

Very awesome write up! Thanks for sharing!


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[wayoflife]

Very awesome write up! Thanks for sharing!

LOL!! Thanks. A video of this is coming very very soon

[JTCO]

Awesome write-up. Thanks for taking the time to put this together.

[Strike Force Zebra]

Two questions, does this stick out of the frame? Do the “tails” stay out?IMG_4981.jpg

And I missed it but does the caster in the front go back to 4 degrees like the JK?




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[BillArnett]

<rant>
It seems like all the factory bolts are metric and all the EVO ones are “standard”. Life would be a lot easier if everyone just used metric!

It’s all Ronald Reagan’s fault. His predecessor started the US on metric conversion. Reagan canceled it. If we had just kept going it would all be done by now and inches and pounds would have receded into history along with cubits and stones. Grrrr.

God only knows how many billions of dollars it costs us each year to be using different measures than the rest of the world.
</rant>

With that out of the way, nice write up Eddie! I was wondering how to set the caster, imagining an angle finder tool or something. Just using the right length in the first place is way easier! (Of course, it will have to be readjusted if different springs are used later but for now, really easy :-)

Question: does the caster angle need to be changed if different sized tires are used?

[13_gecko_rubi]

<rant>
It seems like all the factory bolts are metric and all the EVO ones are “standard”. Life would be a lot easier if everyone just used metric!

It’s all Ronald Reagan’s fault. His predecessor started the US on metric conversion. Reagan canceled it. If we had just kept going it would all be done by now and inches and pounds would have receded into history along with cubits and stones. Grrrr.

God only knows how many billions of dollars it costs us each year to be using different measures than the rest of the world.
</rant>

With that out of the way, nice write up Eddie! I was wondering how to set the caster, imagining an angle finder tool or something. Just using the right length in the first place is way easier! (Of course, it will have to be readjusted if different springs are used later but for now, really easy :-)

Question: does the caster angle need to be changed if different sized tires are used?

The castor isn't directly related to tire size. You could put any tire you want on and if you don't lift it the castor will stay same.

Whenever you lift the vehicle, you are lowering the axle with respect to the frame so the castor will be off and you need to adjust it back. Even a small 1" lift will change it. If you don't the loss of castor reduces the auto centering of the tires and you steering feels flighty. One nice thing about the JL is with FAD the front driveshaft isn't spinning so u can run a tad mote castor and won't get driveline vibration in 2wd. Will still be out in 4wd so don't want to get too aggressive. On my aftermarket axles I had them set so I can run almost 10 deg castor, auto centering for days lol.

Sent via....

[notnalc68]

<rant>
It seems like all the factory bolts are metric and all the EVO ones are “standard”. Life would be a lot easier if everyone just used metric!

It’s all Ronald Reagan’s fault. His predecessor started the US on metric conversion. Reagan canceled it. If we had just kept going it would all be done by now and inches and pounds would have receded into history along with cubits and stones. Grrrr.

God only knows how many billions of dollars it costs us each year to be using different measures than the rest of the world.
</rant>

Yeah, those were the good old days, when we didn’t give a damn what the rest of the world thought. We were still individualists.


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