Lift install, while I'm there stuff to replace

Stock FSJ Tech Area

Topic author
blueday
Posts: 31
Joined: Wed Apr 13, 2022 10:14 am
Location: Louisiana

Lift install, while I'm there stuff to replace

Post by blueday »

Hey fellas,

I have a 1990 Grand Wagoneer. If there's anything I've learned from my C3 corvette and 05 gmc is replace what you can while you're there (within reason).

I'll be going with a 4" lift (skyjacker) with all 4 new springs, drop pitman, extended brake lines, etc. If like to replace other Suspension related parts while I'm there. Is there a parts list to swap out or just go to rock auto and get some part numbers for tiered ends, and other bushings, Ball joints, u joints etc?

Thanks for any advice.

Ryan

sierrablue
Posts: 1208
Joined: Wed Nov 30, 2022 8:02 pm
Location: MN/CO

Re: Lift install, while I'm there stuff to replace

Post by sierrablue »

Only other thing that should really be coming out would be the shackle bushings--you'll wanna replace those while everything's out. Also are your driveshafts long enough that you won't need new ones?

Tie rod ends/drag link are good, but shouldn't need messed with for a lift install (unless they're already bad). Easy enough to replace later if you need to; unlike the Vettes and stuff you can do a lot w/o jacking it up, esp. with the lift. Funny thing about leaf springs...you replace the springs and the shackles and you just replaced the entire suspension system (except the tires obv) lol

I mean you COULD go through and do every single u joint, ball joint, rebuild the axles, and put in a whole brand new steering box and everything, but if there's nothing wrong with that stuff, it's wasteful.

If you're doing the brakes anyway the one thing is I might consider new pads and rotors if they're kind of worn--and if you do the rotors I'd do the wheel bearings.

You might also check the track bar bushings--do you have to get a new track bar for the lift? Or are you just taking it off altogether (probably what I'd do)?
'71 Wagoneer (DD)
-B350 (HEI, iron 4-barrel, Edelbrock 1406), TH400, D20
-'74 D44 front (nonpower discs)
-custom headliner
-Front shoulder belts (rears eventually)

viewtopic.php?t=23070

There are 2 major differences between new Wranglers and FSJs. FSJs are meant to be both utilitarian and capable, not just capable. FSJs are also rarely initially recognized as Jeeps by the average American.
User avatar

Stuka
Site Admin
Posts: 11789
Joined: Thu May 12, 2011 5:53 pm
Location: CA
Contact:

Re: Lift install, while I'm there stuff to replace

Post by Stuka »

As SierraBlue said, the shackle bushings should be done, as that requires unbolting the leaf springs to get to.

The other stuff you note might be bad, but they are independent of the suspension. A lift will typically make a borderline u-joint bad. But TRE and ball joints are not impacted by the springs. And the springs done have to be removed to fix them. But if they are bad, you should consider doing them.

As for the track bars, unless you plan on towing, or spending a lot of time at freeway speeds, I would just remove them. You will need to drop brackets just to allow them to bolt up after the lift. The other suspension bit is the sway bar end links. You will need longer ones.
2017 JKU Rubicon
Pevious Jeeps: 1981 J10, 1975 Cherokee, 2008 JK, 2005 KJ, 1989 XJ
User avatar

tgreese
Posts: 7118
Joined: Fri Jun 08, 2012 6:31 am
Location: Medford MA USA

Re: Lift install, while I'm there stuff to replace

Post by tgreese »

I'd be most worried about the caster angle. Loss of caster seems to happen a lot, increasingly with more and higher lift. The axle is bolted rigidly to the spring; this sets the caster angle. Sufficient caster is essential for the wheels to track straight ahead. Too little caster makes the wheels unstable at center, and you'll need constant corrections to keep the Jeep going in the same direction.

Could not find the caster spec in the later manuals, but earlier books call for 4 +/-1 degrees. In my experience, the 5 to 7 degree range is good for highway stability. Better a little too much than not enough.

I doubt the spring manufacturers consider how their spring geometry affects the caster, especially with lots of lift. I expect they are more concerned with getting a uniform arch to achieve the advertised lift.

You'll need to measure the caster after the lift is done, then add shims to correct the angle. Maybe you can do this with an angle finder on the knuckle, or your local tire shop can help though you'll have to pay them. They can adjust the toe-in and center the steering easily - ask for the printout from the machine. You can add the shims, or pay additional for them to unbolt the axle and put shims in. Be sure to use steel, not aluminum, shims.
Tim Reese
Maine beekeeper's truck: '77 J10 LWB, 258/T15/D20/3.54 bone stock, low options (delete radio), PS/PDB, hubcaps.
Browless and proud: '82 J20 360/T18/NP208/3.73, Destination A/Ts, 7600 GVWR
Copper Polly: '75 CJ-6, 304/T15, PS, BFG KM2s, soft top
GTI without the badges: '95 VW Golf Sport 2000cc 2D
Dual Everything: '15 Chryco Jeep Cherokee KL Trailhawk, ECO Green
Blockchain the vote.

J7M46sn
Posts: 42
Joined: Tue Nov 30, 2021 8:46 am

Re: Lift install, while I'm there stuff to replace

Post by J7M46sn »

I JUST finished installing a 4" Skyjacker (all four springs) kit yesterday on my Jeep J20 truck! As far as your question 'what other stuff to replace while I'm in there' goes, I agree with what's posted already. On mine, I did have to service all of the U joints and grease slip/shafts. On the transfer case, the big nut that holds the yoke on was about a thread loose, which I wasn't even aware of, initially. I also had to replace my transmission and transfer case mounts, and I replaced all shackle bushings as well. The kit came with new extended brake lines, so I replaced all of my original factory ones (sheesh, they were SOFT). I did install a new dropped pitman arm as well. My steering linkage seemed OK at stock ride height, but I don't know if that will change now that it's lifted. I need to re-center my steering wheel too. Because I finished the install late in the day, I didn't want to drive the truck for the first time in the dark, so I don't know what it feels like yet.

I was generally satisfied overall with my experience with Skyjacker, I have nothing bad to report. Anyway, good luck with your install!
Mike
1977 Jeep J20, 360, T18, D20, D44, D60, 4:10s

sierrablue
Posts: 1208
Joined: Wed Nov 30, 2022 8:02 pm
Location: MN/CO

Re: Lift install, while I'm there stuff to replace

Post by sierrablue »

tgreese wrote: Mon Mar 27, 2023 8:43 am I'd be most worried about the caster angle. Loss of caster seems to happen a lot, increasingly with more and higher lift. The axle is bolted rigidly to the spring; this sets the caster angle. Sufficient caster is essential for the wheels to track straight ahead. Too little caster makes the wheels unstable at center, and you'll need constant corrections to keep the Jeep going in the same direction.

Could not find the caster spec in the later manuals, but earlier books call for 4 +/-1 degrees. In my experience, the 5 to 7 degree range is good for highway stability. Better a little too much than not enough.

I doubt the spring manufacturers consider how their spring geometry affects the caster, especially with lots of lift. I expect they are more concerned with getting a uniform arch to achieve the advertised lift.

You'll need to measure the caster after the lift is done, then add shims to correct the angle. Maybe you can do this with an angle finder on the knuckle, or your local tire shop can help though you'll have to pay them. They can adjust the toe-in and center the steering easily - ask for the printout from the machine. You can add the shims, or pay additional for them to unbolt the axle and put shims in. Be sure to use steel, not aluminum, shims.
Isn't the caster is only messed with if you install shims to correct the driveshaft angle? And then it's not that hard to adjust it to toed in 1/16" or so. After that you drive it as is and should only need to adjust the drag link to put the wheel back to straight--which should be roughly the same distance you moved the tie rod end. Or am I way off on this?
'71 Wagoneer (DD)
-B350 (HEI, iron 4-barrel, Edelbrock 1406), TH400, D20
-'74 D44 front (nonpower discs)
-custom headliner
-Front shoulder belts (rears eventually)

viewtopic.php?t=23070

There are 2 major differences between new Wranglers and FSJs. FSJs are meant to be both utilitarian and capable, not just capable. FSJs are also rarely initially recognized as Jeeps by the average American.
User avatar

tgreese
Posts: 7118
Joined: Fri Jun 08, 2012 6:31 am
Location: Medford MA USA

Re: Lift install, while I'm there stuff to replace

Post by tgreese »

sierrablue wrote: Mon Mar 27, 2023 2:46 pm Isn't the caster is only messed with if you install shims to correct the driveshaft angle?
No. True if you intentionally tilt the pinion up, you reduce the caster, unless you rotate the knuckles. That's right. Similarly, the caster changes depending on the springs if the angle of the mounting surface changes. Toe is not related to caster angle.
Or am I way off on this?
Depends on your definition of "way off."

Have you watched Easy Rider? There's a scene where they ride hands-off on the highway. The extreme caster of a chopper makes this possible. Changing the springs carries the caster angle along with the spring mounting surface of the axle. It depends on the arch of the spring, the mounting angle, and the shackle length.

Bicycles are the same way. The angle of the head tube affects stability. A racing bike with a near-vertical head tube is twitchy (maneuverable) while a touring bike where the head tube tilts back is stable.

If you want anecdotal evidence, BDS lift springs on my CJ-6 (a modest 2.5" lift) reduced the caster from the factory 3 degrees to about 1 degree. Not enough caster. Seems universal (a pun) that CJs get lift springs and the caster goes away. Maybe FSJs are different, but I doubt it considering how many threads I've read where adding caster helped handling a lot. I have not kept track, but I expect those Jeeps were lifted.
Tim Reese
Maine beekeeper's truck: '77 J10 LWB, 258/T15/D20/3.54 bone stock, low options (delete radio), PS/PDB, hubcaps.
Browless and proud: '82 J20 360/T18/NP208/3.73, Destination A/Ts, 7600 GVWR
Copper Polly: '75 CJ-6, 304/T15, PS, BFG KM2s, soft top
GTI without the badges: '95 VW Golf Sport 2000cc 2D
Dual Everything: '15 Chryco Jeep Cherokee KL Trailhawk, ECO Green
Blockchain the vote.

Rc4mike
Posts: 8
Joined: Sat Dec 24, 2022 4:19 pm

Re: Lift install, while I'm there stuff to replace

Post by Rc4mike »

Interesting on the caster issue. I just put a BDS 4” on my84 waggy and it’s very twitchy. It had another very old 4” lift and drove fine. I wondering if my caster is now messed up. How much is the wagoneer supposed to have? 3 deg?

sierrablue
Posts: 1208
Joined: Wed Nov 30, 2022 8:02 pm
Location: MN/CO

Re: Lift install, while I'm there stuff to replace

Post by sierrablue »

About 1/16" closer together in the front than in the back.
'71 Wagoneer (DD)
-B350 (HEI, iron 4-barrel, Edelbrock 1406), TH400, D20
-'74 D44 front (nonpower discs)
-custom headliner
-Front shoulder belts (rears eventually)

viewtopic.php?t=23070

There are 2 major differences between new Wranglers and FSJs. FSJs are meant to be both utilitarian and capable, not just capable. FSJs are also rarely initially recognized as Jeeps by the average American.
User avatar

Scotty54
Posts: 98
Joined: Sat Dec 10, 2022 6:08 pm

Re: Lift install, while I'm there stuff to replace

Post by Scotty54 »

While I did a recent BJ's 2" lift, I also replaced all the fuel hoses from the filler neck to the tank, since the fuel pipe had to be removed to remove the driver's side shock. I understand on later models the fuel tank may have to be removed to gain access to the front spring perch (??). If that's the case I would also replace fuel and vent hoses to the motor. Mostly what I did while the springs were out was a general clean up - rust removal, painting, etc. of spring perches and frame components.
1977 Cherokee Chief 401 QT
Northeast Tennessee

rocklaurence
Vendor
Posts: 2565
Joined: Sat Mar 30, 2013 6:53 am

Re: Lift install, while I'm there stuff to replace

Post by rocklaurence »

Caster set to 5-6 degrees is good for most FSJs--thats with the top of the knuckle leaning back towards the rear. My understanding is with 35" or taller tires 2-3 provides better results. Ive always tried to hit 5 degrees.
User avatar

tgreese
Posts: 7118
Joined: Fri Jun 08, 2012 6:31 am
Location: Medford MA USA

Re: Lift install, while I'm there stuff to replace

Post by tgreese »

sierrablue wrote: Wed Mar 29, 2023 5:46 am About 1/16" closer together in the front than in the back.
:?: :?: :?:

That's toe-in, not caster. Caster, camber and toe are all different angles, adjusted differently.
Tim Reese
Maine beekeeper's truck: '77 J10 LWB, 258/T15/D20/3.54 bone stock, low options (delete radio), PS/PDB, hubcaps.
Browless and proud: '82 J20 360/T18/NP208/3.73, Destination A/Ts, 7600 GVWR
Copper Polly: '75 CJ-6, 304/T15, PS, BFG KM2s, soft top
GTI without the badges: '95 VW Golf Sport 2000cc 2D
Dual Everything: '15 Chryco Jeep Cherokee KL Trailhawk, ECO Green
Blockchain the vote.

sierrablue
Posts: 1208
Joined: Wed Nov 30, 2022 8:02 pm
Location: MN/CO

Re: Lift install, while I'm there stuff to replace

Post by sierrablue »

NVM I guess. I know you adjust the toe in, and then for me I just adjusted the drag link until the steering wheel is straight when you're going straight down the road. I don't know what else there is to adjust there, outside of the steering box, which shouldn't change much. I mean you can rotate the knuckles and stuff but what else is there that's adjustable? Leaf springs and a solid axle--where is the other adjustment?
'71 Wagoneer (DD)
-B350 (HEI, iron 4-barrel, Edelbrock 1406), TH400, D20
-'74 D44 front (nonpower discs)
-custom headliner
-Front shoulder belts (rears eventually)

viewtopic.php?t=23070

There are 2 major differences between new Wranglers and FSJs. FSJs are meant to be both utilitarian and capable, not just capable. FSJs are also rarely initially recognized as Jeeps by the average American.

candymancan
Posts: 3652
Joined: Tue Mar 22, 2016 11:32 pm

Re: Lift install, while I'm there stuff to replace

Post by candymancan »

Do your body mounts. Make sure theyre good.. u jiints ball joints only go bad when thry go bad.

Lube the ones you can in the double cardan front drive shaft. And the ball joints and everything elss.

But im betting your body mounts are either gone or flattened
1998 Jeep Grand Cherokee 5.9L Limited 219k
1998 Jeep Grand Cherokee 4.0 I6 laredo 430k
1990 Jeep Grand Wagoneer 155k
1976 Jeep J10.. 85k(repaired)

sierrablue
Posts: 1208
Joined: Wed Nov 30, 2022 8:02 pm
Location: MN/CO

Re: Lift install, while I'm there stuff to replace

Post by sierrablue »

candymancan wrote: Wed Mar 29, 2023 6:34 pm Do your body mounts. Make sure theyre good.. u jiints ball joints only go bad when thry go bad.
Not true. U joints and body mounts have very little to do with each other.
'71 Wagoneer (DD)
-B350 (HEI, iron 4-barrel, Edelbrock 1406), TH400, D20
-'74 D44 front (nonpower discs)
-custom headliner
-Front shoulder belts (rears eventually)

viewtopic.php?t=23070

There are 2 major differences between new Wranglers and FSJs. FSJs are meant to be both utilitarian and capable, not just capable. FSJs are also rarely initially recognized as Jeeps by the average American.

will e
Posts: 5096
Joined: Sat Aug 18, 2012 8:21 am

Re: Lift install, while I'm there stuff to replace

Post by will e »

If you are considering slider bars for your rig, you'll need to temporarily move the gas tank to install them. You most likely will have to move the gas tank to get to the front driver bolt for the rear spring. I installed sliders when I did the lift for this reason.
81 Waggy 'WILL E' Retired
82 Cherokee WT - SOA/SF/high steer/Alcan springs/agr box/Borgeson steering shaft/AMC 401/performer/holley TA/HEI/BeCool/727/ALTAS (2.0/2.72/5.44)/D60 Snofighter(Yukon Zip,hubs,stubs,4.56)/14 Bolt (FF,BF shave, Discs, ARB,Artec Truss)/MTR 37X12.5/Corbeau XRS Baja & 5 point retractable harness/Hella Aux lights/tuffy console/killer32 sliders/Evil Twin bumpers, rack and roll cage/WARN 8000/TT Fabworks steering brace/dual batts/custom TC skid plate/ARB fridge
User avatar

tgreese
Posts: 7118
Joined: Fri Jun 08, 2012 6:31 am
Location: Medford MA USA

Re: Lift install, while I'm there stuff to replace

Post by tgreese »

sierrablue wrote: Wed Mar 29, 2023 3:35 pm ... Leaf springs and a solid axle--where is the other adjustment?
Suggest you read up about steering geometry.

You are correct that the only easily adjusted alignment angles are the toe-in and steering center. However, you can change the caster and camber by installing tapered shims. For caster, you attach the shim on top of (or under) the spring and the center bolt goes through it. This tilts the knuckle forward or backward, and the ball joint axis (caster angle) follows. Shims are commonly added to the rear axle to adjust the rear pinion angle with the driveshaft. No caster on a rear live axle, since there's no pivot. IRS will have a caster angle, though I expect it's much less important than the camber for IRS.

I try not to opine beyond my limited knowledge and experience. It's a skill. If I am in doubt, I do not post, or add extra text to explain my uncertainty.
Tim Reese
Maine beekeeper's truck: '77 J10 LWB, 258/T15/D20/3.54 bone stock, low options (delete radio), PS/PDB, hubcaps.
Browless and proud: '82 J20 360/T18/NP208/3.73, Destination A/Ts, 7600 GVWR
Copper Polly: '75 CJ-6, 304/T15, PS, BFG KM2s, soft top
GTI without the badges: '95 VW Golf Sport 2000cc 2D
Dual Everything: '15 Chryco Jeep Cherokee KL Trailhawk, ECO Green
Blockchain the vote.

sierrablue
Posts: 1208
Joined: Wed Nov 30, 2022 8:02 pm
Location: MN/CO

Re: Lift install, while I'm there stuff to replace

Post by sierrablue »

tgreese wrote: Thu Mar 30, 2023 6:28 am I try not to opine beyond my limited knowledge and experience. It's a skill. If I am in doubt, I do not post, or add extra text to explain my uncertainty.
That's nice.
'71 Wagoneer (DD)
-B350 (HEI, iron 4-barrel, Edelbrock 1406), TH400, D20
-'74 D44 front (nonpower discs)
-custom headliner
-Front shoulder belts (rears eventually)

viewtopic.php?t=23070

There are 2 major differences between new Wranglers and FSJs. FSJs are meant to be both utilitarian and capable, not just capable. FSJs are also rarely initially recognized as Jeeps by the average American.

candymancan
Posts: 3652
Joined: Tue Mar 22, 2016 11:32 pm

Re: Lift install, while I'm there stuff to replace

Post by candymancan »

sierrablue wrote: Wed Mar 29, 2023 6:58 pm
candymancan wrote: Wed Mar 29, 2023 6:34 pm Do your body mounts. Make sure theyre good.. u jiints ball joints only go bad when thry go bad.
Not true. U joints and body mounts have very little to do with each other.

Huh U joint only go bad when they go bad... Its either bad or not. Thats what im saying

The body mounts rubber are probably garunteed to be rotten squished or cracked by now. All i was saying is to look at the body mounts. And the steel they squish on which tends to rust out too. U joints dont have to be replaced if they arent bad which is easy to find out.

Did a FSJ owner die years ago when his body flew off his wagoneer in a accident ? Im shocked yours didnt fly off so yours must still be good. Which is great :-)
1998 Jeep Grand Cherokee 5.9L Limited 219k
1998 Jeep Grand Cherokee 4.0 I6 laredo 430k
1990 Jeep Grand Wagoneer 155k
1976 Jeep J10.. 85k(repaired)
User avatar

tgreese
Posts: 7118
Joined: Fri Jun 08, 2012 6:31 am
Location: Medford MA USA

Re: Lift install, while I'm there stuff to replace

Post by tgreese »

There were some spectacular pictures of a Wagoneer separating from its chassis on IFSJA. However, this Wagoneer was body lifted about 4" (?) above the frame. And the owner did not die; survived just fine in the intact shell that went rolling down the highway embankment.

Says something about body lifts though.
Tim Reese
Maine beekeeper's truck: '77 J10 LWB, 258/T15/D20/3.54 bone stock, low options (delete radio), PS/PDB, hubcaps.
Browless and proud: '82 J20 360/T18/NP208/3.73, Destination A/Ts, 7600 GVWR
Copper Polly: '75 CJ-6, 304/T15, PS, BFG KM2s, soft top
GTI without the badges: '95 VW Golf Sport 2000cc 2D
Dual Everything: '15 Chryco Jeep Cherokee KL Trailhawk, ECO Green
Blockchain the vote.
Post Reply