Who wants upgraded AHC torsion bars?

[krispykritter]

Edit: @cruiserpatch has pre-orders up on his site for the 27mm AHC upgrade bars. Here's a link to his post in another thread: Custom Diameter Torsion Bars (Sway-A-Way) - https://forum.ih8mud.com/threads/custom-diameter-torsion-bars-sway-a-way.1307056/post-15966820

And here's a direct link to the pre-order: Cruiser Patch 100 Series AHC Land Cruiser & LX470 Torsion Bar set (116 - https://www.cruiserpatch.com/products/cruiser-patch-100-series-ahc-land-cruiser-lx470-torsion-bar-set-1160mm-length-27mm-diameter?_pos=2&_sid=6fb55d013&_ss=r

Hello all -

This post is mostly to try and gauge interest specifically in upgraded AHC torsion bars. Anecdotally, it seems like most people decide to rip out the AHC suspension and go with standard and/or lift-kit suspension on the 100 series. Some folks (like me) really like the AHC and plan to keep it as long as possible. However, I've run into the limits of the OEM AHC torsion bars + extended travel IFS, and had to swap over to the non-AHC torsion bars, which solved my bump-steer issues, but made the front end a lot stiffer than I really want.

I contacted Sway-away a while back and tried to get some pricing on new t-bars, but the numbers were kinda extreme for a one-off set. More recently, @cruiserpatch has put in an order for a batch of 29.5mm bars as an OEM-upgrade for the non-AHC suspension, and has suggested he'd be willing/is going to eventually get to a set of AHC-upgrade bars.

If you're interested, I did the math on what that might look like here
@cruiserpatch 's post is here and includes a link to where you can purchase the non-AHC upgraded bars

So, this post is mostly to help cruiserpatch figure out how much demand there might be for the AHC bars. He's stated that the cost for a pair of bars should be similar to the non-AHC bars, which is currently $530. I was to stress that this is NOT a certain figure just yet.

Also, he mentioned turning the bars to 27mm, which would be 26% stiff than the OEM 25.5mm bar. I also calculated that 32% stiffer would make a 27.33mm bar. Dunno if anyone has a thought on those values, but I'd take either. For reference, the non-AHC OEM bar is 63% stiffer than the AHC bar.

The question is - who wants this AND is willing to shell out 500-600 dollars to get it? I'm hoping if there's enough interest or people will to pay a deposit, that @cruiserpatch would be willing to get this project started sooner rather than later. Also - I'm asking for forgiveness rather than permission from cruiserpatch for this post!

People who have expressed interest:
Me! Take my money!
@trdcorolla
@hoser
@paco01
@jtb517
@ranchero7 - interested

Please let me know in this thread.

 

[kevgentile]

As far as price goes, I highly doubt the AHC version will ever be less expensive than the alternative since so many folks seem to delete AHC (worst mistake I ever made on my '99 LX470). For intense rock crawling like I do, AHC would have been perfect for low spring rate, lots of flex- oh well. Live and learn. Perhaps on the next build

Reading thru torsion bar threads as I'm considering converting from AHC to a full Dobinsons MMR/MMA set-up.
I love the AHC and agree with this idea.
Our recent shop field trip to Moab left one truck stranded after an air spring corner failure. After getting off trail I started considering converting since I run 35's, and considering 37's. Would be very challenging on 35+ tires with a similar AHC failure.

 

[ranchero7]

I would be interested. I was skeptical of AHC, but I like it so far. My 2006 is 100% stock, but not for too long. Anticipate aluminum front bumper, winch, campteq top and light interior build. 34s or 35s maybe.

 

[jaewastooshort]

I'm curious whether there is any kind of post-machine heat treat on the TB's, as that would make machining them a much less likely option... If not, I'm curious whether having a set of non-AHC TBs turned down to 27.3mm OD would be a reasonable solution.

 

[krispykritter]

I would be interested. I was skeptical of AHC, but I like it so far. My 2006 is 100% stock, but not for too long. Anticipate aluminum front bumper, winch, campteq top and light interior build. 34s or 35s maybe.

I do love the AHC - it's a surprisingly resilient system. I'll add you to the list.

I'm curious whether there is any kind of post-machine heat treat on the TB's, as that would make machining them a much less likely option... If not, I'm curious whether having a set of non-AHC TBs turned down to 27.3mm OD would be a reasonable solution.

They are heat treated - that was the concern of the guy at sway-a-way about simply turning down a set of their thicker bars. They can (supposedly) turn them down a bit without worrying but too much turning removes too much of the treated layer.

 

[krispykritter]

Reading thru torsion bar threads as I'm considering converting from AHC to a full Dobinsons MMR/MMA set-up.
I love the AHC and agree with this idea.
Our recent shop field trip to Moab left one truck stranded after an air spring corner failure. After getting off trail I started considering converting since I run 35's, and considering 37's. Would be very challenging on 35+ tires with a similar AHC failure.

How did the failure occur? I'm at 200k miles and have replaced all four shocks/rams (around 170k) and all four globes (at 198k), and the system just keeps right on working. This is with it lifted and towing all kinds of ridiculous crap behind the truck. This is on 33s but I plan to go to 35s in the near future, but that's gonna involve extended bump stops to ensure full compression will still avoid mashing a tire into the body/frame.

I am NOT gentle on the AHC system.

 

[kevgentile]

How did the failure occur? I'm at 200k miles and have replaced all four shocks/rams (around 170k) and all four globes (at 198k), and the system just keeps right on working. This is with it lifted and towing all kinds of ridiculous crap behind the truck. This is on 33s but I plan to go to 35s in the near future, but that's gonna involve extended bump stops to ensure full compression will still avoid mashing a tire into the body/frame.

I am NOT gentle on the AHC system.

I beat-up on my AHC as well, especially this most recent trip to Moab. I was hitting several sections of whoops at 30+, never missed a beat.
My only real concern is "if" a failure was to occur with 35"-37" tires it would be very difficult to get off trail. I severely rub when in low as it is.
Probably going to Dobinsons triples soon, and grab a set of Patch'sT-bars. I live full-time out of the LX and it's my only vehicle. While I am
a big pro-AHC fan I can't afford any failures or down-time. The system while relatively healthy has started to get a little glitchy.

 

[krispykritter]

I beat-up on my AHC as well, especially this most recent trip to Moab. I was hitting several sections of whoops at 30+, never missed a beat.
My only real concern is "if" a failure was to occur with 35"-37" tires it would be very difficult to get off trail. I severely rub when in low as it is.
Probably going to Dobinsons triples soon, and grab a set of Patch'sT-bars. I live full-time out of the LX and it's my only vehicle. While I am
a big pro-AHC fan I can't afford any failures or down-time. The system while relatively healthy has started to get a little glitchy.

Yeah fair enough - there's no doubt that AHC adds complication and more failure points to the suspension. Realistically I only ever change height to hitch trailers or work on the LX, and I have a spare car or two!

 

[kevgentile]

Yeah fair enough - there's no doubt that AHC adds complication and more failure points to the suspension. Realistically I only ever change height to hitch trailers or work on the LX, and I have a spare care or two!

Up until the last trip I had plained on retaining AHC forever. I bought brand new rams since the fronts had some corrosion on the shafts. Must of trapped some water between the bushings. Globes are still original to the truck, while in good condition, are nearing the end. The height control is starting to act up and will randomly raise the front end. Been thru the system and data but nothing stands out as the cause.

Hopefully Patch gets the T-bars going soon to compliment the conversion.

 

[hoser]

I beat-up on my AHC as well, especially this most recent trip to Moab. I was hitting several sections of whoops at 30+, never missed a beat.
My only real concern is "if" a failure was to occur with 35"-37" tires it would be very difficult to get off trail. I severely rub when in low as it is.
Probably going to Dobinsons triples soon, and grab a set of Patch'sT-bars. I live full-time out of the LX and it's my only vehicle. While I am
a big pro-AHC fan I can't afford any failures or down-time. The system while relatively healthy has started to get a little glitchy.

If you index the front torsion bars to give it some "leeway," should a front end AHC failure occur, you can crank the stock t-bars enough to give it a decent ride height. The rears... maybe just run timbrems for failsafe insurance.

 

[krispykritter]

If you index the front torsion bars to give it some "leeway," should a front end AHC failure occur, you can crank the stock t-bars enough to give it a decent ride height. The rears... maybe just run timbrems for failsafe insurance.

Yeah I was going to suggest that cranking the t-bars would alleviate the failure case, but realized that didn't work for the rear.

My non-ahc t-bars would handle the front weight fine if the AHC died but most folks aren't running them. Also - are the front and rear systems separate enough that one end could retain pressure even if the other end blew apart?

 

[hoser]

AFAIK, The AHC accumulators are somewhat interchangeable.... as in, if you only carried a rear spare, it can be used in the front position.

Some AHC delete "kits" retain the AHC T-bars. Not really suggested long term, however, they can work short term and as long as the front weight is not excessive. Also, granted there is enough threads on the adjustment bolts and/or they are indexed to work. Carrying a 30mm socket would be needed.

When my LH front height control sensor went out, I disconnected it and test drove for 10 miles, while waiting for my new sensor to arrive. The dash AHC "OFF" light flashed the entire time but the front height was in normal position. I did not really explore that any further but it is worth looking into. Try it out, see how long you can drive with one, good front sensor.

 

[zipdoa]

Interesting. I bought used non-ahc oem t-bars and springs from a 100 a couple years ago.

The springs are stiff unloaded, but perfect for a full set of drawers/fridge/expo load + tongue weight.

I've just added an ARB + Warn 16.5TI-s to the truck, and will be installing the non-ahc bars asap. If it rides like s*** I'm very interested in some 'in between' torsions for AHC trucks.

 

[JohnMed]

I have a bone stock lx470 with original T bars and vehicle has 340k miles. All of my AHC pressures are in good spec, but I had to crank adjustment bolts all the way. So I think these bars are probably fatigued and there is no room for further adjustment. If I were to get the AHC+ T-bars (32% stiffer than stock), I presume that I would be able to get pressures within spec WITHOUT having to crank adjustment bolt much at all? Am I correct in this assumption? However, the ride would be stiffer than (less comfortable?) than replacing with OEM AHC T Bars?

 

[jaewastooshort]

I have a bone stock lx470 with original T bars and vehicle has 340k miles. All of my AHC pressures are in good spec, but I had to crank adjustment bolts all the way. So I think these bars are probably fatigued and there is no room for further adjustment. If I were to get the AHC+ T-bars (32% stiffer than stock), I presume that I would be able to get pressures within spec WITHOUT having to crank adjustment bolt much at all? Am I correct in this assumption? However, the ride would be stiffer than (less comfortable?) than replacing with OEM AHC T Bars?

I'm curious as to what would be expected as well. After adding a front bumper, winch, and RTT, my front feels very stiff/bouncy, and while I haven't checked again yet, I'm assuming my hydraulic pressure is way too high (even after adjusting preload about as far as I can without re-indexing). The rear feels noticeably better after I upgraded to stiffer coils several months back to account for the steel rear bumper and 5th wheel swingout. So, if it feels really stiff and bouncy due to hydraulic pressure being too high and undersprung, I'm not sure what I'd expect out of a higher spring rate with less weight... maybe it would end up under-dampened as the TB would be taking enough load to leave the shocks way under spec.

Looking forward to getting the AHC+ TBs in to hopefully get everything back in spec.

 

[David310]

I went ahead and ordered Patch’s AHC+ torsion bars. With the steel bumper and 12K winch, my front pressure is currently at 7.2. The torsion bars are cranked but haven’t been reindexed. If I lower the ride height back to stock, I can probably bring the front pressure down to around 6.9. Right now, I’m sitting at 20.5” from the center of the front hub to the bottom of the fender, which is about a 0.75” sensor lift.