Coil springs for AHC (3 Viewers)

[jahawk]

Yes that’s what I use: iCarSoft TYTii
$149 on Amazon

Sweet! Buying one tonight.

Jim

 

[kwon-offroad]

Interestingly enough I installed brand new OE Purple/Brown on a 2006 LC (140k) and the pressures didn't change. I was sitting at top of the spec at 6.7.
Now I've ordered spacers (which was kinda what I was trying to avoid in the first place) to get to the pressures I'm after. Seemed odd to me, and a waste of $$$ for the new OE springs. I'm thinking I should've gone Kings to begin with.

I guess if anyone is looking for a set of used but still apparently good OE springs, I've got a set for ya.

Edit: Rookie move. Didn't unplug the temp sensor and now I'm at 6.1mpa. Nothing to see here...

 

[Sargy]

It is a struggle figuring out what the best way to go is here. My system is heavy enough that when I'm loaded, it reverts to low on the AHC. I have a heavy roof top tent (23 Zero walkabout 87), an ARB bull bar, 4 kids, and carry the equivalent of a heavy drawer system in the back, including a kennel with 2 dogs (a shiba and a husky), a Goal Zero 1000 power station and briefcase solar panel, 2 full coolers (1×50 qt. dry and 1x60 qt. Cold), 14 gallons of water, recovery gear, high lift jack, camp kitchen gear, coleman stove, pick, shovel, axe, personal day bags for the 5 of us, basic repair tools and some fluids. The water and 60qt. cooler go on a hitch mount tray.

I also want to get sliders and a rear bumper with swing gate, and I plan on building a drawer system to accommodate it all without a tailgate avalanche..

I like the AHC, but it does me no good in low. Is there any consensus on what the best way to go is? King springs, new OEM springs, spacers, 80 springs, combinations of them all? Reading more threads. I would love to chat with folks who have done similar and get pros and cons. I have the 80 coils in my shed, so that saves a few bucks for this single dad, but I don't want to muss it all up guessing.

Cheers.

Run the 80 springs since you have them. I'm running a Dobinson comfort spring for an 80 series and it works perfect for the heavy rigs out there.

 

[JJ_SC]

I have the Kings and spacers. I'm still a little high on the rear AHC reading. I have a rear bumper, RTT, a bunch of tools and gear, a winch... Kids and dog and the rest. Not as heavy as Otter seems to be, I don't think. But I feel like the truck kinda wallows around in the rear when it's all loaded. However, I have not hit the limit and overloaded since I installed the Kings and spacers.

Those Dobinsons look cool. Everything is so clean under there! I might go that route. I want to add drawer too. It just gets heavier and heavier!

 

[trdcorolla]

Interestingly enough I installed brand new OE Purple/Brown on a 2006 LC (140k) and the pressures didn't change. I was sitting at top of the spec at 6.7.
Now I've ordered spacers (which was kinda what I was trying to avoid in the first place) to get to the pressures I'm after. Seemed odd to me, and a waste of $$$ for the new OE springs. I'm thinking I should've gone Kings to begin with.

I guess if anyone is looking for a set of used but still apparently good OE springs, I've got a set for ya.

Edit: Rookie move. Didn't unplug the temp sensor and now I'm at 6.1mpa. Nothing to see here...

I did the exact same thing as you 3 years ago. New LC AHC Coils and a 30mm spacer. The FSM says to remove the temp sensor to get rear pressures, when I did that, my rears went down .8 more which got me down to 6.0

 

[2manycruisers]

Interestingly enough I installed brand new OE Purple/Brown on a 2006 LC (140k) and the pressures didn't change. I was sitting at top of the spec at 6.7.
Now I've ordered spacers (which was kinda what I was trying to avoid in the first place) to get to the pressures I'm after. Seemed odd to me, and a waste of $$$ for the new OE springs. I'm thinking I should've gone Kings to begin with.

I guess if anyone is looking for a set of used but still apparently good OE springs, I've got a set for ya.

Edit: Rookie move. Didn't unplug the temp sensor and now I'm at 6.1mpa. Nothing to see here...

Unplug temp sensor? Where? I’ve never done that and don’t seem to have any issues with pressure readings.

 

[trdcorolla]

Yup, the FSM says to unplug fluid temp sensor when checking rear AHC pressures. It's in the side of the reservoir, the most rear connector's with 2 wires. My pressure reading was 6.8 plugged in and 6.0 when unplugged. It looks like only some have to do this, I'm one of them.

 

[2manycruisers]

Yup, the FSM says to unplug fluid temp sensor when checking rear AHC pressures. It's in the side of the reservoir, the most rear connector's with 2 wires. My pressure reading was 6.8 plugged in and 6.0 when unplugged. It looks like only some have to do this, I'm one of them.

Thanks, I'll give that a try when I install spacers soon and see if it makes a difference.

 

[saudi]

Im going to install new coils in the rear in a couple weeks. Does anyone have a sense of how new OEM AHC coils compare to used and tired (180k) non-AHC coils? I can get a set of tired used springs for cheap, but I don't want a stiff ride. I may put a 150lb drawer system in the rear sometime this winter, but that's not really much heavier than the 3rd row.

Im running mostly stock weight now, with the exception of a heavy front bumper. Eventually I plan on running a little on the heavy side: extended range fuel tank, rear bumper with spare and swing outs, roof rack, and sliders. I'll probably do these in reverse order over a span of 3-4 years. (Or i go broke, which ever comes first.) With all this extra weight I expect I'll eventually be in the market for new non-AHC or 80 series springs. For now, for the next year or so, I'll be running more or less stock weight over the rear axles.

With whatever coils i put in, im also installing airbags for towing and other heavy conditions. Which should keep me in spec pressure wise between springs.

Thoughts?

I bought king springs from Australia they produce one for ahc but a little stiffer

 

[2manycruisers]

I installed my coil spacers and want to share what I learned. I would recommend coil spring compressors when you do the swap. I didn't use them replacing my coils or adding my spacers. My coils with spacers didn't fit easily, I had to pry them a little to get them in place. In the process, I forced the axle to droop enough to invert the AHC height sensor linkage and bend it. Don't repeat my mistake.

Unfortunately I couldn't access my TechStream before I added the spacer so I don't have before and after readings. I did finally access my TS and tested readings with the AHC temp sensor unplugged. When I first unplugged it I couldn't get any neutral pressure readings at all. After going through the heights a couple times I finally got neutral pressures but no accumulator pressure. Neutral pressures did not seem different than with it plugged in, so I guess I'm not one that has to unplug it.

 

[RainCityCruiser]

Run the 80 springs since you have them. I'm running a Dobinson comfort spring for an 80 series and it works perfect for the heavy rigs out there.

View attachment 2408395

Do you know the Dobinson part number by any chance? They have several rear springs and kinda confused if it's the variable rate or not. Thanks.

 

[Lasagnexl470]

For my 2c, installed kings ktrs-79 springs (ahc specific springs) pressures down at 5.4mpa unloaded,

somone should sticky the spring name.. Simply night and day for rigs that carry extra weight wile still retaining full ahc range, highly recommended.

 

[RainCityCruiser]

For my 2c, installed kings ktrs-79 springs (ahc specific springs) pressures down at 5.4mpa unloaded,

somone should sticky the spring name.. Simply night and day for rigs that carry extra weight wile still retaining full ahc range, highly recommended.

Was trying to find king springs but looks like it's not readily available here in the US. Already messaged some au sellers on ebay if they are willing to ship.

 

[saudi]

For my 2c, installed kings ktrs-79 springs (ahc specific springs) pressures down at 5.4mpa unloaded,

somone should sticky the spring name.. Simply night and day for rigs that carry extra weight wile still retaining full ahc range, highly recommended.

I’ve fitted same and airbags

 

[IndroCruise]

Was trying to find king springs but looks like it's not readily available here in the US. Already messaged some au sellers on ebay if they are willing to ship.

You may also want to try a direct inquiry to King Springs in Australia quoting the King Springs Part Number KTRS-79 and also mentioning the make (Lexus or Toyota), Model and Year of your vehicle. They should be able to tell you about distributors in USA, or Australian distributors who ship to USA -- should not be hard to get springs sent to Seattle.

Home - https://kingsprings.com.au/
Phone: +61 7 5539 6700
Fax: +61 7 5539 6881
For Australian Enquiries
E-mail: sales@kingsprings.com.au
For All Overseas Enquiries
E-mail: export@kingsprings.com.au

Similar to the post and pictures by @saudi, I also replaced original (old and tired) OEM rear springs with King KTRS-79 springs and added Firestone Coilrite airbags with kevlar sleeves inside the coils, running at 5 psi to hold shape when vehicle is not loaded. The KTRS-79 spring rate is about 130 pounds per inch compared with around 95 (?) pounds per inch for new OEM springs. In my case, this reduced the rear AHC neutral pressure to about 5.1 Mpa for the empty vehicle (almost stock with third row seats in place but no rear bar, no rear drawers, no driver, no pax, half-full OEM fuel tanks).

Unsurprisingly, the low rear AHC pressure makes the ride a bit "springy" in the unloaded condition but it is not unacceptable. The rear AHC pressure can be increased a bit by increasing height at the rear with some "sensor lift" while being careful of excessive rake affecting front end geometry. When loaded for touring with passengers and their stuff plus usual remote travelling paraphenalia (mainly recovery gear, tools, additional spare wheel), rear AHC pressures are well back into the FSM-specified range, the ride returns to normal and all is good. Damping variability works well and AHC raise/lower function aIso works properly at all three height settings.

I suspect that friction between spring coils and airbags may contribute to increased AHC raise/lower times, although the airbag supplier denies this.

For my purposes, I now think that the airbags are 'overkill' because I do not intend add a rear bar nor drawers, roof rack, trailer, super heavy loads etc. I am very happy with the springs but the airbags have never been put to serious use.

Others have settled for airbags to give load flexibility without spring replacement. However, all "100 series" vehicles with AHC are at least 14 years old, and almost certainly are in need of replacement of the tired, lightweight AHC original rear coils if not already done. If springs are to be replaced, it is worth considering the upgrade to King KTRS-79.

[The correct neutral rear pressure range specified in the Factory Service Manual is 5.6 MPa to 6.7 Mpa without sub-tank (or in my case 5.9 Mpa to 7.0 Mpa with the additional OEM sub-tank), all measured at standard conditions. Damping performance usually is better towards the lower end of the range -- and this allows for some load variation without developing excessive pressures].

 

[Lasagnexl470]

You may also want to try a direct inquiry to King Springs in Australia quoting the King Springs Part Number KTRS-79 and also mentioning the make (Lexus or Toyota), Model and Year of your vehicle. They should be able to tell you about distributors in USA, or Australian distributors who ship to USA -- should not be hard to get springs sent to Seattle.

Home - https://kingsprings.com.au/
Phone: +61 7 5539 6700
Fax: +61 7 5539 6881
For Australian Enquiries
E-mail: sales@kingsprings.com.au
For All Overseas Enquiries
E-mail: export@kingsprings.com.au

Similar to the post and pictures by @saudi, I also replaced original (old and tired) OEM rear springs with King KTRS-79 springs and added Firestone Coilrite airbags with kevlar sleeves inside the coils, running at 5 psi to hold shape when vehicle is not loaded. The KTRS-79 spring rate is about 130 pounds per inch compared with around 95 (?) pounds per inch for new OEM springs. In my case, this reduced the rear AHC neutral pressure to about 5.1 Mpa for the empty vehicle (almost stock with third row seats in place but no rear bar, no rear drawers, no driver, no pax, half-full OEM fuel tanks).

Unsurprisingly, the low rear AHC pressure makes the ride a bit "springy" in the unloaded condition but it is not unacceptable. The rear AHC pressure can be increased a bit by increasing height at the rear with some "sensor lift" while being careful of excessive rake affecting front end geometry. When loaded for touring with passengers and their stuff plus usual remote travelling paraphenalia (mainly recovery gear, tools, additional spare wheel), rear AHC pressures are well back into the FSM-specified range, the ride returns to normal and all is good. Damping variability works well and AHC raise/lower function aIso works properly at all three height settings.

I suspect that friction between spring coils and airbags may contribute to increased AHC raise/lower times, although the airbag supplier denies this.

For my purposes, I now think that the airbags are 'overkill' because I do not intend add a rear bar nor drawers, roof rack, trailer, super heavy loads etc. I am very happy with the springs but the airbags have never been put to serious use.

Others have settled for airbags to give load flexibility without spring replacement. However, all "100 series" vehicles with AHC are at least 14 years old, and almost certainly are in need of replacement of the tired, lightweight AHC original rear coils if not already done. If springs are to be replaced, it is worth considering the upgrade to King KTRS-79.

[The correct neutral rear pressure range specified in the Factory Service Manual is 5.6 MPa to 6.7 Mpa without sub-tank (or in my case 5.9 Mpa to 7.0 Mpa with the additional OEM sub-tank), all measured at standard conditions. Damping performance usually is better towards the lower end of the range -- and this allows for some load variation without developing excessive pressures].

this would be the best idea, if all fails this, im happy to look at exporting a bunch for forum members in a bulk buy being based in aus... might save on shipping

 

[RainCityCruiser]

You may also want to try a direct inquiry to King Springs in Australia quoting the King Springs Part Number KTRS-79 and also mentioning the make (Lexus or Toyota), Model and Year of your vehicle. They should be able to tell you about distributors in USA, or Australian distributors who ship to USA -- should not be hard to get springs sent to Seattle.

Home - https://kingsprings.com.au/
Phone: +61 7 5539 6700
Fax: +61 7 5539 6881
For Australian Enquiries
E-mail: sales@kingsprings.com.au
For All Overseas Enquiries
E-mail: export@kingsprings.com.au

Similar to the post and pictures by @saudi, I also replaced original (old and tired) OEM rear springs with King KTRS-79 springs and added Firestone Coilrite airbags with kevlar sleeves inside the coils, running at 5 psi to hold shape when vehicle is not loaded. The KTRS-79 spring rate is about 130 pounds per inch compared with around 95 (?) pounds per inch for new OEM springs. In my case, this reduced the rear AHC neutral pressure to about 5.1 Mpa for the empty vehicle (almost stock with third row seats in place but no rear bar, no rear drawers, no driver, no pax, half-full OEM fuel tanks).

Unsurprisingly, the low rear AHC pressure makes the ride a bit "springy" in the unloaded condition but it is not unacceptable. The rear AHC pressure can be increased a bit by increasing height at the rear with some "sensor lift" while being careful of excessive rake affecting front end geometry. When loaded for touring with passengers and their stuff plus usual remote travelling paraphenalia (mainly recovery gear, tools, additional spare wheel), rear AHC pressures are well back into the FSM-specified range, the ride returns to normal and all is good. Damping variability works well and AHC raise/lower function aIso works properly at all three height settings.

I suspect that friction between spring coils and airbags may contribute to increased AHC raise/lower times, although the airbag supplier denies this.

For my purposes, I now think that the airbags are 'overkill' because I do not intend add a rear bar nor drawers, roof rack, trailer, super heavy loads etc. I am very happy with the springs but the airbags have never been put to serious use.

Others have settled for airbags to give load flexibility without spring replacement. However, all "100 series" vehicles with AHC are at least 14 years old, and almost certainly are in need of replacement of the tired, lightweight AHC original rear coils if not already done. If springs are to be replaced, it is worth considering the upgrade to King KTRS-79.

[The correct neutral rear pressure range specified in the Factory Service Manual is 5.6 MPa to 6.7 Mpa without sub-tank (or in my case 5.9 Mpa to 7.0 Mpa with the additional OEM sub-tank), all measured at standard conditions. Damping performance usually is better towards the lower end of the range -- and this allows for some load variation without developing excessive pressures].

Thank you so much for the very informative reply. I'll give this a try.

 

[LXKevin]

KING SPRINGWORKS +61 7 5539 6700 (Mick Stubbings Export Coordinator)
sales@kingsprings.com.au
KTRS-79 (Cost About $278.00 delivered to the USA)
AUD $226.00
DHL Freight
AUD $155.00

 

[yngmrostrvile]

Wholesalesuspension.com.au has the KTRS-79 for 170 AUS$. Im waiting to hear how much freight is.

 

[flintknapper]

Yes that’s what I use: iCarSoft TYTii
$149 on Amazon

^^^^^

Use this also.

You can read AHC values with it, ABS codes and much more. But you'll want to download the latest updates and install them at the same time you register it. Its a little bit complicated....but once done....it works fine.