Seems like the move is to add rear spacers if you are going to attempt the sensor lift to help keep ahc pressures in spec?
AHC Sensor Adjustment for Lift
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Or, add king springs. Depends on what you intend to do with it...
Spacers if you just want the lift and no additional weight changes to the rear of the vehicle
Stiffer / taller springs if you want the lift and add weight
Both, if you want more height and anticipate even more weight. E.g. replacement rear bumper/armor with swingout tire carrier, gas cans, etc.
Yes, but really you should be measuring pressures. If you do a sensor lift and we assume you are starting with good pressures (you have to measure otherwise the more accurate assumption is that your pressures are terrible), you need to compensate for that with stiffer springs or spacers to maintain that pressure balance.
AHC is a combo of mechanical and hydraulic support. They work together to hold the car up. The hydraulic support force is relatively fixed. If you want to raise the vehicle you have to run higher pressures (which is dumb) or you have to modify the mechanical support (spacer or higher spring-rate springs, like King).
Regardless of doing a sensor lift or not, get your pressures. They're often wrong and very easy to fix.
I decided to try and give the rear a little bump up to get the rake back. And I couldn’t get the nut off. And the linkage kinda twisted in a way I’m not positive it should. Does it kind of have some twist to it to account for the movement? I sure hope so. Either way it’s soaking in on blaster and I have a new link sub assembly ordered just in case I broke something. I need to stop touching stuff 
Edit: it looks like the threading sticking out from the arm does have some wiggle/rotation to it, huh? Okay maybe I didn’t break anything. I’ll just stick with the pb blaster for now.
Edit: it looks like the threading sticking out from the arm does have some wiggle/rotation to it, huh? Okay maybe I didn’t break anything. I’ll just stick with the pb blaster for now.
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I'm wondering if someone can ellaborate on this process a little to get to 2.5" sensor lift in front? I mean specifically shortening the helm joint... A cut off wheel?
Attached is a photo of my setup currently, arrows pointing to the things I assume they're referencing, and then the photo for reference from this quote showing the result.
Yes will get you to about 2.5", but I would not recommend going past 2". Be prepared to lose some handling characteristics & your CV boots will most likely leak. In addition, I installed some SPC adjustable upper corntrol arms to help me get back the caster that I lost with the 2:" lift.
Just did mine, here are some pictures;
Shortened the L&R joints, before and after measurements;
Added a bracket in the rear to raise the eye level of the joint, rear Ironman 30mm trim packer is also visible;
Before and after front AHC shock mount spacer.
Rear AHC shock spacer;
Shortened the L&R joints, before and after measurements;
Added a bracket in the rear to raise the eye level of the joint, rear Ironman 30mm trim packer is also visible;
Before and after front AHC shock mount spacer.
Rear AHC shock spacer;
I only want 1" or so of sensor lift
LCT
SILVER Star
Thanks for sharing the pictures! Do you have dimensions on that rear bracket? Also, are shock spacers required to stuff 34/35's?
Just installed 295/70/18 rt trails and getting ready to do all the mods needed to avoid rubbing.
Yes I did the shock spacers because I moved up from 275/70R18 to 35x12.5R18. I don’t have measurements of the DIY bracket I made for the rear height sensor, but I think eye-to-eye is 2-inches and then you can just move it up and down depends on how much rake you want in the back.
Thanks for the pics. I am getting ready to do exactly what you did here and use the Toyko 4x4 spacers. Do you feel like the 30mm spacer was enough in the rear?
*Japan 4x4. Oops
For now yes it fits my needs, don’t have a 300+ Lbs steel bumper w/ swing outs at the back and 100+ Lbs. storage system. I haven’t installed my 35” spare tire in the oem underbody location yet and will decide from there if I will swap to LC oem springs or Kings KTRS AHC springs.
I did this yesterday, gained about 1.5” in neutral. Didn’t have to lift the truck, just adjusted the sensors when the vehicle was off.
I’d argue it rides much smoother even though some have claimed it’s more stiff. I didn’t shorten the sensor bolts or extend the track in the rear, just maxed out what was already there. Truck still has the LX feel in comparison to my LC.
Thanks for the write up!
I’d argue it rides much smoother even though some have claimed it’s more stiff. I didn’t shorten the sensor bolts or extend the track in the rear, just maxed out what was already there. Truck still has the LX feel in comparison to my LC.
Thanks for the write up!
Keep in mind as @suprarx7nut mentioned above.
When doing a sensor lift. You must also set AHC Mpa (pressures) within spec. Failure to do so. You'll be riding on excessive AHC pressure. You will blow your globes. How long until they blow. Depends on load (weight) and age of globes.
With a full rear sensor lift, when NOT adding extension brackets to height sensors. You'll want King AHC coils with ~20mm donuts (spaces) on top of coils, when at stock weight. With weighted cargo area, iron bumpers, spare tire carrier swing out ect. adding weight. You may want 30mm spacers. Goal is 5.6 Mpa (ideal, globes last the longest) to 6.7 (high limite) Mpa rear.
You'll then set, front height sensors, so you have at least 3/4" of rake (front-end lower than rear-end, AKA: Stink bug look).
Then crank up T-bars. By turning 30mm adjust bolt clockwise (CW), until cross leveled in N and correct pressure reached of 6.9 +/-0.5Mpa
Tips:
Clean threads of T-bar adjuster bolts, and lube threads.
Cross level and read pressures while on level ground with tire pressure check/set evenly side to side.
Jack up front end or set AHC to H. To take weight of T-bars, as you turn adjusting bolts CW.
When doing a sensor lift. You must also set AHC Mpa (pressures) within spec. Failure to do so. You'll be riding on excessive AHC pressure. You will blow your globes. How long until they blow. Depends on load (weight) and age of globes.
With a full rear sensor lift, when NOT adding extension brackets to height sensors. You'll want King AHC coils with ~20mm donuts (spaces) on top of coils, when at stock weight. With weighted cargo area, iron bumpers, spare tire carrier swing out ect. adding weight. You may want 30mm spacers. Goal is 5.6 Mpa (ideal, globes last the longest) to 6.7 (high limite) Mpa rear.
You'll then set, front height sensors, so you have at least 3/4" of rake (front-end lower than rear-end, AKA: Stink bug look).
Then crank up T-bars. By turning 30mm adjust bolt clockwise (CW), until cross leveled in N and correct pressure reached of 6.9 +/-0.5Mpa
Tips:
Clean threads of T-bar adjuster bolts, and lube threads.
Cross level and read pressures while on level ground with tire pressure check/set evenly side to side.
Jack up front end or set AHC to H. To take weight of T-bars, as you turn adjusting bolts CW.
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How many splines are you going to offset on Patch’s torsion bars? I was thinking of going with 5.
Looking to do this on my 05. I just want to adjust the ahc enough to level the front out. Will the torsion bars need to be adjusted to help hold the weight of the front end? Also, how do you find out the pressure of the globes are at?
First there is suppose to be at least a 1/2 in rake for the truck to ride well.
2nd. Yes if you raise or lower anything it will effect the AHC presures . And consequently torsion bar adj. is needed.
3rd. You'll need a OBDII scaner to read the presures.
2nd. Yes if you raise or lower anything it will effect the AHC presures . And consequently torsion bar adj. is needed.
3rd. You'll need a OBDII scaner to read the presures.
I recently re-cross leveled and after getting the pressures to 6.3-6.4 front and 6.1-6.2 rear while filled with a full tank of gas, but no other gear. I mostly use the truck for longer 4wd trips and when fully loaded I am seeing 6.7 front and 7.7 rear. I have king springs at the rear but I don't have spacers. I have sliders, skids, drawers but no bumpers. Is 7.7 way out of line for the rear - should I try cranking the tb's cw to take some more pressure off the ahc before going to spacers?