TreatSmash
SILVER Star
FWIW I spent the weekend wheeling with senior Toyota development engineers at Overland Expo East and they told me to keep my AHC.
I have a 2006 LC w/165k, it's still working fine, and I like it.
The ABCs of AHC - How to Measure, Flush, and Adjust all in one place (3 Viewers)
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FWIW I spent the weekend wheeling with senior Toyota development engineers at Overland Expo East and they told me to keep my AHC.
I have a 2006 LC w/165k, it's still working fine, and I like it.
TreatSmash
SILVER Star
I really, really want to figure out how to make it cycle with the rear hatch open.
AHC is awesome. You will not find a better ride with any aftermarket solution. I have 300K on mine. I replaced the actuators last year and everything is great!
Read and learn how to maintain it here and you won’t regret it.
AHC is awesome. You will not find a better ride with any aftermarket solution. I have 300K on mine. I replaced the actuators last year and everything is great!
Read and learn how to maintain it here and you won’t regret it.
That's way too much.
Even here in Australia a 2.5 liter AHC fluid was less then AUD$50.
Suggest keep in mind that
AHC pressures – whether high or low or as FSM-specified – tell nothing about ‘globe’ condition. If the measurements were made correctly after height movements N > LO > N, then these numbers just indicate that excessive share of the vehicle weight is being carried by the AHC part of the suspension system, and, too low share of the vehicle weight is being carried by the mechanical part of the suspension system (meaning front torsion bars and rear coils springs), OR, it means that the after-market additions to the vehicle have made it very heavy.
Either way, correction requires front torsion bar adjustment (and/or possibly re-indexing), and, at least pre-loading the rear springs with spacers (and/or upgrading the rear springs such as with KING KTRS-79 replacements).
Excessive AHC pressures mean poor damping performance and less than best ride comfort. It also risks leakage at valves and seals, especially the internal seals in the ‘shock absorbers’.
Graduation change – the FSM-specified guidance for change in AHC Fluid level at the AHC Tank between “HI” height and “LO” height applies when the AHC pressures are within the FSM-specified ranges. Then ~14 graduations difference between "HI" and
"LO" means ‘globes are as new’. When the reading declines to 7 graduations it means ‘replace all globes' – because nitrogen pressure behind the membranes in the ‘globes’ is now too low for effective damping performance.
When AHC fluid pressures are excessive for whatever reason, then the change in graduations test is not comparable with FSM-specified guidance. For example, if AHC fluid pressures are high, then the nitrogen pressures behind the membranes in the ‘globes’ are less able to push fluid back to the tank than when AHC fluid pressures are correct. This will result in a lower reading than when AHC fluid pressures are within FSM-specified ranges.
The nitrogen pressures behind the membranes in the ‘globes’ cannot be measured directly because there is no valve fitting on the ‘globes’ to enable gas pressure to be measured. Instead, the FSM offers this indirect approach to indicate the overall condition of the four ‘globes’ taken together (meaning, using fluid displacement to indicate indirectly whether or not the remaining nitrogen gas pressure is adequate for reasonable damping performance and ride comfort).
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I flushed my AHC fluid today and ran a few pressure checks. I’m getting very low pressure readings every few tests. PO said he replaced the globes a couple years ago but when I ran the graduation test it says they need to be replaced. Anybody have a similar situation? I don’t know if my graduation test is accurate with the pressure jumping around.
How did you do the test?
Did you go from N to H?
Did you go from N to H?
I ran it twice once from high to low and then from low to high. As you can see it didn’t move much.
From my understanding, you need to run it from N to H, N is the standard height which should have the pressures in spec.
But indeed, it hasn't moved much if that is from Low to High.
But indeed, it hasn't moved much if that is from Low to High.
PabloCruise
SILVER Star
I thought graduation test was between L and H?
And pressure test was from L to N?
And pressure test was from L to N?
PabloCruise
SILVER Star
This is a great post and confirms my above points about testing.
But pay attention to the idea that if pressures are not w/in spec, graduation test is not valid.
Agreed -- as mentioned in my post #325 above -- "the FSM-specified guidance for change in AHC Fluid level at the AHC Tank between “HI” height and “LO” height applies when the AHC pressures are within the FSM-specified ranges".
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I added a circuit interrupting switch into my hatch so that I could leave it open with the lights off (without switching from DOOR) and now my AHC will cycle with the door open. It was really easy: cut the sensor wire coming from the lock and install a SPST switch. When the switch is closed, it will bypass the open sensor, thinking the hatch is closed and *all associated functionality will resume (lights turn on as expected, AHC cycling, etc.) When the switch is open, it will think your hatch is open, regardless, so that triggers various things like automatic re-lock if a door isn't opened within 20seconds(?) of unlocking with the fob, AHC won't cycle, etc. I'll open mine up and take some pictures if that will help.
Update: Wow, friends...such an incredible difference!!
My accumulators arrived from IMPEX Japan on Wednesday so I spent a couple hours that night bleeding, draining, lubricating, torquing, removing, replacing, etc. and then I decided to work on the AHC. (jk) It was about a 2 hour job for me with the truck on the ground, no jack stands. Both of my front accumulators were completely failed and full of fluid...and the fluid collected was almost black.
I immediately took the truck for a spin and was blown away by the extreme difference. It felt like I was riding on a magic carpet. Upon return home I did a complete post-test-drive safety check, too, so don't worry about that.
This may sound reckless and immature but I'm going to share anyway: since Wednesday I've been hunting for worse and worse road conditions, potholes, speed bumps, speed humps, arrogant cyclists, etc. just to see how fast I can fly over them. Guys....I can't. believe. the difference. The truck was smooth before the front accumulators failed, but I don't remember it being this velvety.
Thank you to all of you who helped and encouraged.
Full cost details below.
I will connect to techstream later today and share the new numbers in case anyone else is interested.
Thanks again, especially @LndXrsr, @PabloCruise, @mazdababy, and @IndroCruise for the extra detail
Walker
My accumulators arrived from IMPEX Japan on Wednesday so I spent a couple hours that night bleeding, draining, lubricating, torquing, removing, replacing, etc. and then I decided to work on the AHC. (jk) It was about a 2 hour job for me with the truck on the ground, no jack stands. Both of my front accumulators were completely failed and full of fluid...and the fluid collected was almost black.
I immediately took the truck for a spin and was blown away by the extreme difference. It felt like I was riding on a magic carpet. Upon return home I did a complete post-test-drive safety check, too, so don't worry about that.
This may sound reckless and immature but I'm going to share anyway: since Wednesday I've been hunting for worse and worse road conditions, potholes, speed bumps, speed humps, arrogant cyclists, etc. just to see how fast I can fly over them. Guys....I can't. believe. the difference. The truck was smooth before the front accumulators failed, but I don't remember it being this velvety.
Thank you to all of you who helped and encouraged.
Full cost details below.
I will connect to techstream later today and share the new numbers in case anyone else is interested.
Thanks again, especially @LndXrsr, @PabloCruise, @mazdababy, and @IndroCruise for the extra detail
Walker
TreatSmash
SILVER Star
Please give me some more details and a picture or two. It's crazy that you just posted this because I literally was working on my car today and kicking the tire because I couldn't raise and lower it with the back hatch open.
Hey, I'm looking to get new globes too. At IMPEX, when I key in the front globe part number and rear, it shows the price at only $120. Is that per globe, so do I need to add two of the front and rear? Or is it the whole rear kit that includes two globes??
That is the price for each globe. You'll need 2 of the front and 2 rears
Hmm...that's weird. I just looked again and the current USD to JPY conversion puts them at $112 each for me. If you're going to replace all four globes, you will need two of 49141-60010 and two of 49151-60010.
(In my opinion, the term "kit" is misleading as there's only one part in each "kit.")
TreatSmash
SILVER Star
Are these the only parts you should buy other than fluid? What other parts of the AHC system are wear items that could be replaced as part of a re-haul?
I currently get 7 graduations and will probably be replacing the globes next spring.
Height Control Sensors always come to mind -- see a few thoughts at Post #2 at the link below:
03 LX470 AHC issue, shop diagnosis?
Evening Fellas, I suppose I could write a novel but I’ll try for the quick and dirty. We had our clean 03 Fla LX470 into the most local Lexus Indi in Portland Maine today for a harsh ride issue in the front end. I was thinking the torsion bars needed adjustment or possibly a globe issue. The...
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