Improving Off road capability in AHC equipped AHC (1 Viewer)

[Moridinbg]

The HDJ torsion bars are proportionally thicker to compensate with bigger spring rate for the heavier engine, compared to the UZJ, so the stock starting point is about the same.

 

[jLB]

Quite interestingly I had a similar issue with my non-AHC 98, once I build it up with heavier stuff. The non-AHC TBs were able to hold the truck up when static but weren't able to handle the dynamic load very well and that caused the ride to suffer badly. Heaver gauges TBs remedied that!

To some degree, shouldn’t it be the shock valving’s (and swaybar’s) job to control the dynamic load, and the spring’s job to support the static load. Yes, you could add stiffer springs, but isn’t that just reducing active suspension travel?

 

[JJ_SC]

I really like the way the Wheeler Bump stops have made my AHC feel. Maybe it’s a quick and easy solution to the bottoming out issue. (Which I’ve never noticed - but, I only have a winch under the stock bumper, so maybe not quite as heavy.)

 

[jLB]

I really really wish I had non-AHC torsion bars, but in Europe we don't have LXs and all the LC 98-07 are AHC equipped so they are extremely hard to get. Petrol torsion bars are also a different length than diesel.

They probably wouldn’t be cheap, but shouldn’t they be available through partsouq?

 

[hoser]

@Moridinbg Yes, I agree they are thicker but probably not thick enough. The vast majority of TD 100's in Australia don't have AHC. Even the non-AHC Torsion bars are not enough.

But comparing your AHC HDJ to a Petrol AHC 100, it would be interesting to know if the suspension damping programs are any different between the two given the difference in weight and weight balance.

 

[ClassyJalopy]

To some degree, shouldn’t it be the shock valving’s (and swaybar’s) job to control the dynamic load, and the spring’s job to support the static load. Yes, you could add stiffer springs, but isn’t that just reducing active suspension travel?

Ideally the shock valving on AHC should also be re-programmed along with heavier springs but unfortunately I am not sure that is even do-able. I think the 'sport' setting on the AHC switch does make the shocks stiffer. I now run my truck at the one-click-from-stiffest setting all the time because the two softer settings make the truck bounce up and down a lot.

So my thinking here is that slightly thicker springs (rears are already King KTRS-79) will support he AHC through out the motion range of the suspension and not just at the resting height. This should improve the ride and allow me to be able to use the two softer settings on the AHC too!

I plan to source thicker TBs and try it out and report back my butt dyno readings! I know it made a huge difference on my non-AHC truck!

 

[hoser]

For those inclined, Sway-a-way offers custom torsion bars. They already offer them for the 100 in 31mm so perhaps it would be just as easy as a phone call and a credit card. 27mm would be right in between AHC and Non-AHC spring rate. They can also turn down existing Torsion bars and remove 1-2 mm off.

https://swayaway.com/

T-bar diameters (not diesel):
Ironman, TJM, Tough Dog 32mm
Sway Away 31mm
OME is 30.5mm
OEM, non-AHC 28.87mm
AHC 25.5mm

 

[Cantatan]

OP, what year is your 100? I completely disagree about lockers if you have ATRAC and want "just a little more offraod capable" that is good to go in "soft sand, snow, mud etc. only".

ATRAC works great, but IMO the biggest limiting factors on the 100 is ground clearance...it's nonexistent compared to my 4th gen 4Runner. And the cheesy plastic "engine cover" (wanna be skidplate) under the LX...wth is that? Can't imagine what running aired down does there.

My observations based on owning both an '04 V8 4Runner, and an '06 LX 470 the past 15+ years. My 4Runner has been all over Death Valley and Panamint Valley and a few places in Eastern Sierra. That's with a mild lift and slightly larger tires (265/70/17) still on stock wheels, Hanna sliders and a Shrockworks front bumper. I've barely offroaded the LX as it's the wife's pavement princess but there's no hiding the weak atributes of its poor ground clearance and poor underbelly protection.

I'm in the same boat as wanting to get my 100 at least slightly more offroadable. I'm hoping that going up to one of the largest size tires that'll fit on the factory wheels, and proper skid plates, will be all I'll need for my intended purposes of a few nights of camping/trail-running at a time. Will likely add step-sliders too. I'm hoping that the exta lift the AHC offers in 4WD will help tons on the ground clearance. Add Staun deflaters and an air tank or battery tire inflater and you should be good to go in "n soft sand, snow, mud etc. only."

I have an 06 with ATRAC, I am running Hancook Dynapro's AT 285/75/R16.

All Im doing is taking girlfriend to Anzo Borrego to look at wild flowers. I'm thinking getting some recovery boards, taking my hi-lift, snatch stap and garmin in-reach. I'm probably being over paranoid but if I don't have the equipment she will probably panic and not want to go.

Main concern is soft sand or mud, most likely will have another vehicle with us so snatch strap probably all I need.

 

[hoser]

If your buddy is going, all you need is a snatch strap, recovery points and a way to air up (pressure gauge too).... even then, you probably won't even use the strap.

 

[cryptyk]

I have an 06 with ATRAC, I am running Hancook Dynapro's AT 285/75/R16.

All Im doing is taking girlfriend to Anzo Borrego to look at wild flowers. I'm thinking getting some recovery boards, taking my hi-lift, snatch stap and garmin in-reach. I'm probably being over paranoid but if I don't have the equipment she will probably panic and not want to go.

Main concern is soft sand or mud, most likely will have another vehicle with us so snatch strap probably all I need.

Was just out there (slot canyon) last weekend and going again this weekend. If you're just looking at wildflowers, you'll be fine. The desert is pretty forgiving as long as you stay on the trails and don't try to show off
If you have an inreach and recovery boards, you're in even better shape. Just don't dig yourself in. Use them early if you get stuck. There shouldn't be any mud.

If there's one thing I would suggest it's an air compressor. Airing down your tires is really helpful out there, but you need a way to air them back up. That's only if you're spending a bunch of time out there are looking to offroad in the gnarlier sections.

Have fun and wave if you see a black LX470 go by!

 

[Cantatan]

Was just out there (slot canyon) last weekend and going again this weekend. If you're just looking at wildflowers, you'll be fine. The desert is pretty forgiving as long as you stay on the trails and don't try to show off
If you have an inreach and recovery boards, you're in even better shape. Just don't dig yourself in. Use them early if you get stuck. There shouldn't be any mud.

If there's one thing I would suggest it's an air compressor. Airing down your tires is really helpful out there, but you need a way to air them back up. That's only if you're spending a bunch of time out there are looking to offroad in the gnarlier sections.

Have fun and wave if you see a black LX470 go by!

Yup I have a compressor, thanks for all the advice

 

[JJ_SC]

I have an 06 with ATRAC, I am running Hancook Dynapro's AT 285/75/R16.

All Im doing is taking girlfriend to Anzo Borrego to look at wild flowers. I'm thinking getting some recovery boards, taking my hi-lift, snatch stap and garmin in-reach. I'm probably being over paranoid but if I don't have the equipment she will probably panic and not want to go.

Main concern is soft sand or mud, most likely will have another vehicle with us so snatch strap probably all I need.

You'll have a great time. It's beautiful out there. If anything, you'll probably use the snatch strap to pull your buddy out!

 

[jLB]

So my thinking here is that slightly thicker springs (rears are already King KTRS-79) will support he AHC through out the motion range of the suspension and not just at the resting height. This should improve the ride and allow me to be able to use the two softer settings on the AHC too!

I believe that the flaw in that logic, is that (if my math is correct) the 28.87mm non-AHC bars are ~64% increase in stiffness over the 25.5mm AHC bars. That seems like a rather large jump, but good luck with your experiment.

For those inclined, Sway-a-way offers custom torsion bars. They already offer them for the 100 in 31mm so perhaps it would be just as easy as a phone call and a credit card. 27mm would be right in between AHC and Non-AHC spring rate. They can also turn down existing Torsion bars and remove 1-2 mm off.

One of my “bitches” about this platform, is that everyone offers a variety of rear coils, and (1) petrol, (1) diesel torsion bar, due to the length difference.

If Sway-A-Way, can offer custom, or turned down bars, at a reasonable price, it would seem to give a much better option to tune AHC:

25.5mm
26mm +8%
26.5mm +16.6%
27mm +25.7%
27.5mm +35%
28mm +45%

It might even give non-AHC folks better options between:
Stock.
OME +25%
32mm +51%