The 80 series springs I have have 215k on them and were pretty squishy when removed. the 100 series springs have 88k and were quite firm when removed. I figured that gives me some variety with what I can do. I will start with the older softer 80 series springs first with a 30mm spacer and see how it rides and what the pressures are.
Towing with AHC
- Thread starter LandCruiserPhil
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This is perfect and exactly what I was hoping would happen. I guess I assumed it was a little too easy and would likely work out different.
For a more leveled look but retaining weight bearing capabilities, could the front height sensors be adjusted front torsion bars be turned with the addition of the 30mm rear spacer?
I don't see why not. I adjusted the front sensors to about 2.25" of extra height and then turned the tbars 5 full turns to get me back close to stock pressure. The front has about .75" of adjustability built into it without any modifications to the sensor. That might be enough to get you close to level. I would do around 2 full turns on the tb's and call it good.
Can you PM me with your setup? Pictures would be awesome as well
I've PM'd taco. But for those interested... I didn't do anything special other than using an lightweight Anderson 'No Sway' weight distribution hitch. Absolutely no sway. And of course, I had done preventative maintenance by making sure my AHC system was re-calibrated to be in spec.
I figured I would update this thread. I picked up a camping trailer this week and wanted to get some stiffer springs out back to help the AHC with the trailer. I had some heavily used 80 series spring that I tried first. I have about 2" of lift out back and am running 30mm spacers on top of the stock AHC springs. I simply swapped out the springs (leaving the spacers). Guess what? Bad idea. The 80 series springs are WAY too stiff with the AHC AND 30mm spacers. It road like crap and I could not get the AHC to even go into the "L" mode in the back. The vehicle could literally not push the springs down enough to get into low. The light would just flash and then eventually go back to N. I will be removing the 30mm spacers in the morning and see how that goes. If that doesn't work then I will just go back to how I had it and hope the AHC can handle the new trailer. I'm just worried with the BIOR rear bumper, 33.5" spare, trail gear, camping gear, AND a trailer the AHC is going to crap itself.
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- Thread starter
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What dont you like about air bags?
Absolutely nothing. I'm just broke and was trying to get creative with what I had laying around in the garage. Every cent I had went to the trailer. I will try the 80 series springs with no spacers tomorrow and see how that rides. If it rides good and the AHC goes up and down then I will load up all the gear and trailer and go for a drive. If all is good then it will stay that way. If I run into issues then I will start a fund for the air bags.
So I pulled the 30mm spacers out and just ran the 80 series springs. I really thought this was going to be the perfect balance. Wrong!! Now the AHC wont budge. I push up to go into H and it just flashes for a few seconds and then the upper light goes off the the middle light stays on. I push into the "L" mode and the same thing happens. I then got out and realized the LX is already in the "L" mode yet the dash light shows "N". What the hell? I figured the AHC must REALLY hate the 80 series springs so I swapped in the factory stock AHC springs with the 30mm spacers. Been running this set up for a few months without issue. I figured all would be good again once I went back to the working set up I had before. I started the car and the same issue persists. I decided to go for a drive to see if a drive would correct the issue. About 100 yards into my drive the AHC is now flashing "off". I have zero control of the system and it is stuck in the "L" position front and back. Any ideas what went wrong. My hope is that since the pressures jumped around so much between one spring to another that the system freeked out. I decided to disconnect the battery in hopes to "re-set" the system. I am typing this message now as I have the battery disconnected. I doubt this will fix it. Could I have damaged the rear sensor in my removing and installed of the rear coil springs?
I have techstream and have used it in the past but not for error codes. Unfortunately my laptop to run it is at work so this will all have to wait until then. I just reconnected the battery and the issue persists. I also replaced the two fuses under the hood still no go. I I think I replaced the two under the dash but I'm not sure. My fuse cover under the dash is missing so I don't know what fuses are what. I looked at a pic from an old thread and did my best guess. Does anyone know for certain which fuses under the dash control the AHC? Hopefully techstream will help me out tomorrow.
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I'm looking through old threads and realizing that the fuse panel under the dash can be very different between years. I have an 03 LX470. If anyone can snap a pic of the diagram on the cover from an 03 I would greatly appreciate it.
Never mind on the fuse panel pic. I found the problem. I destroyed the rear height sensor. I kept it attached to the control arm when I dropped the axle to remove the coil springs. The severely bent the sensor arm which through the sensors WAY outside the norm range. I bent it back and then damaged it even more in the process of bending it back. It will at least now allow the car to ride in the "N" setting but it's in really bad shape. I have to replace it. Hopefully I can find a used one. Anyone got a use rear AHC sensor laying around?
This was probably the cause of the issues you were having with the other springs as well.
Yep. That means I have to start over with testing the different coil spring combinations. Entire day wasted.
So the trip I referenced earlier in this thread has arrived and we leave Saturday. As such I've got a couple of stupid little questions I thought I'd ask here.
I bought a Prodigy P3 brake controller off the local classifies used in good shape and picked up the harness from Amazon. I have a white wire thats hanging off the wire loom that I'm not sure what to do with. Do you guys have one of these and where is it supposed to go? I can't say I read the instructions and they have now been misplaced. (Pic for reference)
I did get the spacers installed and they helped my numbers but I know I need to crank my torsion bars a bit. I thought I read somewhere that you need to get an alignment after you do that but I've put it off too long and don't know that I'll have time before the trip. Because of this I haven't adjusted the front. Is this correct? Do I need an alignment if I turn the TBs?
Lastly, more of a comment then a question. I did a test tow about a month ago just for a few miles near my parents house. Obviously power wasn't what I was used to towing a brick but the biggest thing I noticed was how bad visibility was. I couldn't see anything! I mentioned it to my co-worker and he brought me some extended mirrors to borrow. These are the ones he lent me. When I picked up the trailer earlier this week I stuck the mirrors on and found them to work well. The suction seemed strong and I was really pleased that they could be adjusted with the electronic controls in the cab. Do you guys have experience with this style mirror? They did fine on the short trip I did on the freeway but my trip is going to be just over 2000 miles.
Anyway, thanks for the info in this thread, I'm a little anxious about towing the trailer with my rig but know that it'll handle it just fine. I had wondered whether I should just borrow my parents 2010 crewmax Tundra (with the cute 4.6 V8) but want the comfort of my rig for this trip.
I bought a Prodigy P3 brake controller off the local classifies used in good shape and picked up the harness from Amazon. I have a white wire thats hanging off the wire loom that I'm not sure what to do with. Do you guys have one of these and where is it supposed to go? I can't say I read the instructions and they have now been misplaced. (Pic for reference)
I did get the spacers installed and they helped my numbers but I know I need to crank my torsion bars a bit. I thought I read somewhere that you need to get an alignment after you do that but I've put it off too long and don't know that I'll have time before the trip. Because of this I haven't adjusted the front. Is this correct? Do I need an alignment if I turn the TBs?
Lastly, more of a comment then a question. I did a test tow about a month ago just for a few miles near my parents house. Obviously power wasn't what I was used to towing a brick but the biggest thing I noticed was how bad visibility was. I couldn't see anything! I mentioned it to my co-worker and he brought me some extended mirrors to borrow. These are the ones he lent me. When I picked up the trailer earlier this week I stuck the mirrors on and found them to work well. The suction seemed strong and I was really pleased that they could be adjusted with the electronic controls in the cab. Do you guys have experience with this style mirror? They did fine on the short trip I did on the freeway but my trip is going to be just over 2000 miles.
Anyway, thanks for the info in this thread, I'm a little anxious about towing the trailer with my rig but know that it'll handle it just fine. I had wondered whether I should just borrow my parents 2010 crewmax Tundra (with the cute 4.6 V8) but want the comfort of my rig for this trip.
No need for an alignment. Your front height will stay the same, youre essentially transferring some of the weight from the shocks onto the torsion bars.
You'd only need an alignment if you adjusted the front height sensors.
You'd only need an alignment if you adjusted the front height sensors.
The white wire is a ground wire.....needs to be grounded. One of the many metal screws under the dash work well.