uHu
Bridgeburner
That is correct for the part of this earth called the U S A. The rest of us had it as an option from the very beginning of the LC 100 series in 1998.
Last edited:
Updating AHC system (1 Viewer)
- Thread starter jjrowe
- Start date
This site may earn a commission from merchant affiliate
links, including eBay, Amazon, Skimlinks, and others.
here is a comparison of stock lx470 and 80 series springs. Doesn’t seem as tall as the 100 springs
It's been a year, at least, since I bought amd installed LC springs on my 05 LX. It had been doing OK on the pressures, but would sometimes bump into L when i hooked up my smallish trailer, loaded up. Tried the TB adjust.
Spoke to Slee, bought some used LC springs,
and the result has been mixed. The springs were quite longer. Of course the AHC no longer is selectable, and the ride is stiffer. But my trailer issues were mitigated. If I have the energy, may put the original springs back in and try spacers.
Spoke to Slee, bought some used LC springs,
and the result has been mixed. The springs were quite longer. Of course the AHC no longer is selectable, and the ride is stiffer. But my trailer issues were mitigated. If I have the energy, may put the original springs back in and try spacers.
For a trailer, you should be trying airbags. Get your neutral pressures without the trailer and without bags at the very bottom of spec. Use king and or rear spacers to get you there. Then add the air bags and adjust air bag pressures as needed.
Refreshing the topic.
How come the KTRS-79 springs (free coil height 430 mm) can fit plug-and-play TLC AHC rear coils (500 mm free spring height)?
Isn't it going to drop the standrd height on the back a bit, then?
Trying to get more AHC occasional load here (max +150 kg) so thinking about putting KTRS-79 as predecessors did.
Will it fit then, as King Springs state - they are AHC dedicated no-lift springs?
How bad is the "no extra load" ride? (my usual daily setup)
With no extra load will it still drop to LOW?
Thanks for any experience.
How come the KTRS-79 springs (free coil height 430 mm) can fit plug-and-play TLC AHC rear coils (500 mm free spring height)?
Isn't it going to drop the standrd height on the back a bit, then?
Trying to get more AHC occasional load here (max +150 kg) so thinking about putting KTRS-79 as predecessors did.
Will it fit then, as King Springs state - they are AHC dedicated no-lift springs?
How bad is the "no extra load" ride? (my usual daily setup)
With no extra load will it still drop to LOW?
Thanks for any experience.
I believe, if you're at stock height, the KTRS-79 springs will handle vehicle load fine. They may be shorter, but they are also stiffer so don't compress as much with the standard weight on them. Ditto with extra load in the rear.
But, I added 2" poly spacers to my rear when I added the KTRS-79 in order to allow me to lift the truck and keep my AHC pressures in a happy place. This also allows me to tow a 2000 lbs trailer with about 300lbs of tongue weight without AHC overloading.
The kings were noticeably stiffer than the stock springs, but the furthest thing from harsh. The kings + cranked t-bars yielded a very nice ride with or without extra weight.
In order to fix an unrelated issue, I later added non-ahc front t-bars. This stiffened things up considerably up front, but left the rear very noticeably softer.
I recently removed the king springs and added in the longer LX450 rear springs, which should be around 150 lbs/in vs the kings at 130 lbs/in. Unfortunately, with my non-ahc t-bars, the spring balance is still off, and the rear feels significantly softer than the front. I'm working with someone local to get his 80 series LC springs once he swaps in something aftermarket, which should be 170 lbs/in and will hopefully even out my front to rear spring bias a bit.
With all these various combinations, I've never had AHC drop to low, even when moving from Florida to Colorado with a completely full trailer and trunk and back seat.
Has anyone considered a custom spring setup for their AHC-equipped Hundy? By nearly every account, the Kings springs are too stiff for unloaded driving, and OEM springs are slightly under-sprung occasional trailer-towing etc. Firestone bags would work (and be adjustable), but it also seems that springs with the correct rate would be the best solution.
The biggest issue IMO is that there aren't any choices for higher capacity AHC torsion bars. There was a thread on here recently where someone talked about getting some custom made that would hopefully split the difference between the light AHC bars and the relatively heavy non-AHC bars.
Personally, I didn't think the kings were a bad thing with an empty truck: noticeably stiffer without being anywhere near stiff.
I've slowly made my way up this table through literally every spring here, and just installed the 80 LC springs yesterday. They've done a pretty good job balancing my too-stiff t-bars. I also set my front AHC pressure at the low end of the spec to help keep the stiffness down. Adding the LC rear springs forced me to lift the whole truck an inch or so to get the rear AHC pressure to the right spot, followed by cranking the front and adjusting the sensors to level the truck.
I've got a list somewhere, but spring rates that 'work' with AHC are as follows (
| Name | Rate | Free Length |
| OEM 100 AHC Rear Springs | 90 lbs/in | Didn't record |
| King KTRS-79 | 130 lbs/in | 17 3/8 inch |
| 80 Series LX450 | 150 lbs/in | D 18 1/2, P 17 1/2 inches |
| 80 Series LC | 170 lbs/in | Didn't measure when I had them out |
Last edited:
There is clearly less flex with the new rear springs + cranked non-ahc t-bars. I haven't quite dialed in the front yet, however - the pressures were a little over 7 mpa here. I'll be getting them more like 6.4-6.5 before calling it good, i just ran out of time yesterday after breaking an adjuster link and kludging a fix together with zip ties.
The 'nice' thing, as it were, is my minimum clearance to the body is a little higher now thanks to the decreased compression, particularly in the rear.
Here's the rear compression with the LX450 springs (on a bigger rock as well though):
The 'nice' thing, as it were, is my minimum clearance to the body is a little higher now thanks to the decreased compression, particularly in the rear.
Here's the rear compression with the LX450 springs (on a bigger rock as well though):
I have not read this read through, so forgive me if its covered.
Not sure your ID and length, but the eibach motorsports catalog or the OME spring catalog may be your friend. Find your own rate and length to meet your needs.
I have not read this read through, so forgive me if its covered.
Not sure your ID and length, but the eibach motorsports catalog or the OME spring catalog may be your friend. Find your own rate and length to meet your needs.
OME spring catalog - Google Search - https://www.google.com/search?client=firefox-b-1-d&q=OME+spring+catalog ...around page 150
Do they even make torsion bars? Someone elsewhere mentioned sway-away would build custom t-bars for the 100 in whatever diameter I watned for around 500$, but as for the rear springs, there are generally enough options to allow someone who wants to keep AHC to find a decent option for their vehicle weight. Plus, the rear springs are different diameters at each end.
On the TB's, Not sure TBH. My response was around rear springs and to advise that there are more than the 4 options noted in the table.
I did change my rear springs to non-AHC used LC100 springs many years ago.
The reason was that the car dropped to low with a loaded car and camper trailer. With these springs never had an issue anymore.
The reason was that the car dropped to low with a loaded car and camper trailer. With these springs never had an issue anymore.
n=1 here and that's not our experience at all. When compared to our previous LC with 2" lift and Dobinson springs, it's a magic carpet ride.
The big advantage for us is towing our 180kg ball weight camper trailer and a load in the back, the AHC copes really well having the King Springs.
However our globes are in excellent condition, with ~12 gradations (graduations?) between L and H.
