Builds The Story of Blue (5 Viewers)

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Time for a new rear sensor. I'd go genuine Toyota.


Ordered the rear height sensor. While waiting for it, I flushed the all 4 corners with fresh fluid. This is my second flush in 3 months. The fluid came out full of air bubbles! is that normal? I flushed almost 2 liters of fluid and it still was coming out foamy!
 
Ordered the rear height sensor. While waiting for it, I flushed the all 4 corners with fresh fluid. This is my second flush in 3 months. The fluid came out full of air bubbles! is that normal? I flushed almost 2 liters of fluid and it still was coming out foamy!
On all corners? Equally bubbly everywhere?

Could be dead globe(s), accumulator or bad pump seal.
 
Ordered the rear height sensor. While waiting for it, I flushed the all 4 corners with fresh fluid. This is my second flush in 3 months. The fluid came out full of air bubbles! is that normal? I flushed almost 2 liters of fluid and it still was coming out foamy!


Basically agree with @suprarx7nut -- have added a few more thoughts.

Bubbles mean gas, either air trapped in the system, or, the membranes in one or more old 'globes' are giving up and leaking nitrogen gas into the system.

Given reasonable difference in HI/LO graduations (11 mentioned previously -- done at correct AHC pressures?), expect that overall the four 'globes' are good -- but that does not completely eliminate the possibility of one 'globe' being bad.

Could use "16 Step Test" (formally called the "Damping Force Controlling Condition Check") per Pages 5 and 6 of the attachment to see IF suspension responses are different at different corners. Different response could be either (a) problems within Damping Force Control Actuators to which 'globes' are attached, or (b) one 'globe' is in a worse condition than the other three. As there are gas bubbles, that might suggest 'globe' rather than 'actuator'.

However, there are multiple similar stories on multiple threads which in the end are resolved by multiple cycles of bleeding to get persistent and reluctant air out of the system, involving four to six litres of fluid.

Here is one of my previous comments:

replacing AHC globes/accumulators - https://forum.ih8mud.com/threads/replacing-ahc-globes-accumulators.716383/page-19#post-13972824

Two other possible issues are worth mentioning:
  • a failed Rear Height Control Sensor is a common cause of AHC grief and can put the system into so-called 'fail safe' mode in which AHC does not work properly and damping is locked at Step 8 of 16 Steps. Ride then feels rough, especially at town speeds,
  • a combination of KTRS-79 rear coils and together with stiff tyres at high pressures will feel firmer than stock arrangements. (I have these springs plus BFG KO2 "E" rated tyres running at 40 psi -- noticeably firmer when vehicle is empty but not unacceptable, and very good when the vehicle is loaded for touring).
In addition to the questions by @suprarx7nut , is the AHC system working properly?
 

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Yo Classy, keep bleeding/recycling fluid until the bubbles are gone from the globes. You may be purging air from the tube accumulator the painful way. I feel your pain.
 
Had some free time today so drained and refilled both diffs and the transfer case.
Then noticed this gem: leaking front diff pinion seal. Welp no matter - disconnected the driveshaft, pulled the locking pinion nut, and replaced with new Toyota seal and locking nut - hopefully it will hold.

20210801_112605.jpg


20210801_121141.jpg
 
Had some free time today so drained and refilled both diffs and the transfer case.
Then noticed this gem: leaking front diff pinion seal. Welp no matter - disconnected the driveshaft, pulled the locking pinion nut, and replaced with new Toyota seal and locking nut - hopefully it will hold.

View attachment 2748086

View attachment 2748087
Ask the prior owner of he had a crush sleeve or solid spacer installed. If it was a solid spacer, you don't need to worry about the bearing preload.
 
Ask the prior owner of he had a crush sleeve or solid spacer installed. If it was a solid spacer, you don't need to worry about the bearing preload.
I carefully counted the number of turns in hopes of keeping the preload the same.
But it would be a good idea to ask about the spacer vs. crush sleave
 
Now if this all does mean that I need to replace the rear height sensor, then is AISIN good enough? is hst026 the correct AISIN part number?

AISIN is supplier to Toyota of a lot of Toyota OEM components. Toyota is a significant stockholder in AISIN -- see Stock Information & Ratings | AISIN CORPORATION Global Website - https://www.aisin.com/en/investors/stock/ . Toyota also is a significant stockholder in DENSO -- State of Shareholders | Stock and Corporate Bond Information | Investors | Who we are | DENSO Global Website - https://www.denso.com/global/en/about-us/investors/stock/overview/ . As seems to happen with Japanese companies, there are lots of cross-stockholdings, for example DENSO also is a stockholder in AISIN, and AISIN is stockholder in DENSO.

Anyway, my recently bought OEM Rear Height Control Sensor came in a Toyota packaging with the expected Toyota part number 89407-60010 -- and the brand AISIN stamped on the bracket! Don't know the AISIN number. Regardless of what goes on behind the scenes, for vital items I prefer to buy Toyota/Lexus parts -- but at a good price, sometimes from local Toyota/Lexus dealers, sometimes off-shore from known suppliers with a street address, an e-mail address and a phone number like Partsouq (UAE), Megazip (Singapore), Amayama (Japan) -- been burnt a few times with fake parts on eBay, but not saying all eBay suppliers are unreliable.

Rear Height Control Sensor Pic 1.jpg
 
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I wanted to get an accurate picture of the AHC parameters before I replace the rear height sensor. So I filled up the 40G LRA tank 🤑, connected the Techstream and the following screenshot. I do see the pressures higher than 6.7 front and 6 rear.

For fronts I tried to crank on the torsion bars but unfortunately, they are maxed out :( Now I need to re-index them too!

As for the rears, I think the King KTRS springs are probably too feeble for this heavy beast. I measured the coil thickness - Kings are 15mm and the OEM LC springs are 16.5mm. Also, the rear end pogo-ed a lot less with the LC springs. Looks like I will be swapping out the rear springs again!

Here's the screenshot for my AHC. For the record, it moves from L to N to H very quickly, never fails to raise the truck and has never blinked it's OFF light
4.PNG
 
Front needs about 4 more turns of the TB bars, and rear, maybe shim a 30mm coil spacer on top of the King springs to preload it some, and that should get your AHC back into spec. What the heck are you carrying bro, my last trip i loaded mine up with over 1500lbs of crap and my AHC with stock springs and a little shim was still in spec.
 
Front needs about 4 more turns of the TB bars, and rear, maybe shim a 30mm coil spacer on top of the King springs to preload it some, and that should get your AHC back into spec. What the heck are you carrying bro, my last trip i loaded mine up with over 1500lbs of crap and my AHC with stock springs and a little shim was still in spec.
yes - I will need to re-index the fronts, I just ran out of time and patience today!

I am pretty sure the rear Kings will have to get swapped out for the LC springs. Prev. owner installed the LC version torsion bars and rear springs and this might have been the reason.
Here's a list of all the additional stuff installed on the truck:
ARB Bull bar
ARB dual tire swing out with 35" tire on 18" Tundra steelie
Gamiviti full length steel rack
WKOR steel step sliders
Single ARB drawer
40G LRA gas tank
Twin batteries under the hood
ARB single compressor on the front bumper
WARN 12K lbs winch with nylon rope

I am sure I am forgetting a few things but these should be the major ones
 
yes - I will need to re-index the fronts, I just ran out of time and patience today!

I am pretty sure the rear Kings will have to get swapped out for the LC springs. Prev. owner installed the LC version torsion bars and rear springs and this might have been the reason.
Here's a list of all the additional stuff installed on the truck:
ARB Bull bar
ARB dual tire swing out with 35" tire on 18" Tundra steelie
Gamiviti full length steel rack
WKOR steel step sliders
Single ARB drawer
40G LRA gas tank
Twin batteries under the hood
ARB single compressor on the front bumper
WARN 12K lbs winch with nylon rope

I am sure I am forgetting a few things but these should be the major ones

Probably seen previously -- this is the guidance from the FSM concerning load limits of the AHC system on a stock vehicle ....

1627948977541.png

.... so anything above these numbers would need to be carried by the springs/torsion bars. There are a LOT of kilograms (pounds) in your list.

It seems like your AHC system is still working -- raising LO > N > HI normally (?) -- and that would suggest that you are within these AHC limits but high AHC pressures are indicating that more spring/torsion bar strength is required to carry the load, as you already suspect.

It goes beyond your posts, but you may need to see where you are concerning axle load limits etc. These are found at Page 214 in the Owners Manual for my 2006 LC100 in Australia, pasted below. The layout of the Owners Manual in USA probably is different but the load limit numbers are likely to be the same wherever they are found. It is possible that these numbers are detailed on the manufacturers plate on the vehicle. It is difficult to imagine an axle actually being broken -- the point is to keep an eye on potential fatigue cracking developing over time at various places on the vehicle, including around suspension connections. In particular, the torsion bar connections at the Lower Control Arms and the brackets and fittings around the torsion bar adjusters are well known problem areas.

In Australia we are stuck with an overall maximum allowable Gross Vehicle Mass (GVM) of 3,260 kilograms (7,187 pounds) on LC and LX 100 series vehicles (slightly different for LC105 series) including everything on or in the vehicle. This means accessories and additions, fuel, driver and passengers and all their stuff, everything -- beyond which the vehicle is deemed unroadworthy with all sorts of legal consequences and insurance problems, unless a Government-certified GVM Upgrade has been obtained and plated on the vehicle. The situation in USA may not be so restrictive.

LC100 Axle Loads.jpg
 
Looks like I should find a scale to weigh my truck!
 
In Australia we are stuck with an overall maximum allowable Gross Vehicle Mass (GVM) of 3,260 kilograms (7,187 pounds) on LC and LX 100 series vehicles (slightly different for LC105 series) including everything on or in the vehicle. This means accessories and additions, fuel, driver and passengers and all their stuff, everything -- beyond which the vehicle is deemed unroadworthy with all sorts of legal consequences and insurance problems, unless a Government-certified GVM Upgrade has been obtained and plated on the vehicle. The situation in USA may not be so restrictive.

View attachment 2748737
Interesting!

I recently did some napkin math for the weight of my truck with all the mods and such, and determined that I would be close to, but not above, GVM. My thoughts included a 10% increase to the realistic payload, as I thought that these trucks were underrated from the factory.

In the US, the 100 Series is given a payload of 1470lbs, which means the GVM (or GVWR as we call it) is 6830, or 357lbs less than the Australian GVM rating with the same engine. That's really interesting considering the suspension and axles are the same.

In the US, weight is more or less ignored for non-commercial vehicles, at least where I live. Nobody checks, and vehicle overload isn't policed or generally an issue with insurance. I've seen vehicles in accidents that were severely overloaded and their insurance didn't e even blink. I definitely think there's several built vehicles out there whose owners should think about weight more.
 
Interesting!

I recently did some napkin math for the weight of my truck with all the mods and such, and determined that I would be close to, but not above, GVM. My thoughts included a 10% increase to the realistic payload, as I thought that these trucks were underrated from the factory.

In the US, the 100 Series is given a payload of 1470lbs, which means the GVM (or GVWR as we call it) is 6830, or 357lbs less than the Australian GVM rating with the same engine. That's really interesting considering the suspension and axles are the same.

In the US, weight is more or less ignored for non-commercial vehicles, at least where I live. Nobody checks, and vehicle overload isn't policed or generally an issue with insurance. I've seen vehicles in accidents that were severely overloaded and their insurance didn't e even blink. I definitely think there's several built vehicles out there whose owners should think about weight more.

Mmmmm – I am not sure that I really can explain these differences in weight numbers but here is a the basis of a guess ….

For obscure reasons, Australian Government officials have certified all 100 series Independent Front Suspension (IFS) variants with same Gross Vehicle Mass (GVM) of 3,260 kilograms (7,172 pounds). They did not differentiate the GVM of these IFS variants – all are the same. (Earlier variants and the 105 series with the rigid front axle and different front suspension similar to 80 series have a slightly different GVM).

The IFS 100 series included variants with the 1HD-FTE 6 cylinder turbodiesel engine and variants with the 2UZ-FE V8 petrol (gasoline) engines.

The 1HD-FTE engine (not sold in USA) is more than a 120 kilograms (240 pounds) heavier than the 2UZ-FE engine, so this has to be included in the GVM – and maybe Toyota negotiated some allowance with the certifiers.

In addition, Australian-delivered 100 series with 2UZ-FE come with a main tank 145 litres (38 US gallons) plus the “subtank” of 50 litres (13 US Gallons). There was a slight difference in the Australian-delivered vehicles with 1HD-FTE – main tank 141 litres plus sub-tank of 45 litres. Full fuel also has to be included in the GVM.

Suspect, but not sure, that US-delivered 100 series came with 96 litre (25 US gallons) main tank -- seems low? And no sub-tank?

So, my guess is that the GVM allocated to the Australian IFS 100 series was a one-size-fits-all, intended to cover all the variants with one GVM, with some included allowance for the heavier variants. Maybe that is why the Australian GVM looks so different to the US GVWR.

The kerb weights published by Toyota (stock vehicle, full fuel, no persons, no load, no accessories, no fittings) for the Australian-delivered IFS 100 series variants range from 2,356 kilograms (5,183 pounds) to 2,735 kilograms (6,017 pounds) for the top-of-line model with all the trimmings. GVM is fixed so payload reduces to 525 kilograms (1,155 pounds) at the top-of-line model called ‘Sahara’ in Australia. Compliance is ‘challenging’ when armour, passengers and their gear are loaded!!

Maybe the main focus should be on the Toyota-recommended axle limits:
Front: 1,630 kilograms (3,594 pounds)
Rear : 1,950 kilograms (4,299 pounds)
Total : 3,580 kilograms (7,893 pounds)

Anyway, apologies for the trivia and to @ClassyJalopy for stealing his thread!!
 
Mmmmm – I am not sure that I really can explain these differences in weight numbers but here is a the basis of a guess ….

For obscure reasons, Australian Government officials have certified all 100 series Independent Front Suspension (IFS) variants with same Gross Vehicle Mass (GVM) of 3,260 kilograms (7,172 pounds). They did not differentiate the GVM of these IFS variants – all are the same. (Earlier variants and the 105 series with the rigid front axle and different front suspension similar to 80 series have a slightly different GVM).

The IFS 100 series included variants with the 1HD-FTE 6 cylinder turbodiesel engine and variants with the 2UZ-FE V8 petrol (gasoline) engines.

The 1HD-FTE engine (not sold in USA) is more than a 120 kilograms (240 pounds) heavier than the 2UZ-FE engine, so this has to be included in the GVM – and maybe Toyota negotiated some allowance with the certifiers.

In addition, Australian-delivered 100 series with 2UZ-FE come with a main tank 145 litres (38 US gallons) plus the “subtank” of 50 litres (13 US Gallons). There was a slight difference in the Australian-delivered vehicles with 1HD-FTE – main tank 141 litres plus sub-tank of 45 litres. Full fuel also has to be included in the GVM.

Suspect, but not sure, that US-delivered 100 series came with 96 litre (25 US gallons) main tank -- seems low? And no sub-tank?

So, my guess is that the GVM allocated to the Australian IFS 100 series was a one-size-fits-all, intended to cover all the variants with one GVM, with some included allowance for the heavier variants. Maybe that is why the Australian GVM looks so different to the US GVWR.

The kerb weights published by Toyota (stock vehicle, full fuel, no persons, no load, no accessories, no fittings) for the Australian-delivered IFS 100 series variants range from 2,356 kilograms (5,183 pounds) to 2,735 kilograms (6,017 pounds) for the top-of-line model with all the trimmings. GVM is fixed so payload reduces to 525 kilograms (1,155 pounds) at the top-of-line model called ‘Sahara’ in Australia. Compliance is ‘challenging’ when armour, passengers and their gear are loaded!!

Maybe the main focus should be on the Toyota-recommended axle limits:
Front: 1,630 kilograms (3,594 pounds)
Rear : 1,950 kilograms (4,299 pounds)
Total : 3,580 kilograms (7,893 pounds)

Anyway, apologies for the trivia and to @ClassyJalopy for stealing his thread!!

No apologies needed. You are a gold mine of LC info and have been very generously sharing it - I definitely appreciate it.
 
AISIN rear height sensor arrived from Roack Auto. Quite encouragingly it even say Toyota on the part and the label has the correct Toyota part number 894007-60010.
Install was straight forward and barely took 15 minutes. All excited, I went for the test drive and noticed the ride is slightly less bumpy but still quite bad - like super uncomfortably bad! :poop:

So, slightly heart broken but I think the next step is to get the pressures lowered by re-indexing the torsion bars, swapping in LC springs and bleed the 4-6 liters of AHC fluid to see if I can get away without investing in new globes.
At what point does one say eff it, I am switching to conventional setup?

@suprarx7nut and @IndroCruise thanks for your help with sorting this out.


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20210803_110737.jpg
 
Oh and forgot to add: The transition from L - N - H is now pretty smooth even in the rear. It take about 2.5 sec to go from L to N and about 5 sec to go from L to H!
 
Mmmmm – I am not sure that I really can explain these differences in weight numbers but here is a the basis of a guess ….

For obscure reasons, Australian Government officials have certified all 100 series Independent Front Suspension (IFS) variants with same Gross Vehicle Mass (GVM) of 3,260 kilograms (7,172 pounds). They did not differentiate the GVM of these IFS variants – all are the same. (Earlier variants and the 105 series with the rigid front axle and different front suspension similar to 80 series have a slightly different GVM).

The IFS 100 series included variants with the 1HD-FTE 6 cylinder turbodiesel engine and variants with the 2UZ-FE V8 petrol (gasoline) engines.

The 1HD-FTE engine (not sold in USA) is more than a 120 kilograms (240 pounds) heavier than the 2UZ-FE engine, so this has to be included in the GVM – and maybe Toyota negotiated some allowance with the certifiers.

In addition, Australian-delivered 100 series with 2UZ-FE come with a main tank 145 litres (38 US gallons) plus the “subtank” of 50 litres (13 US Gallons). There was a slight difference in the Australian-delivered vehicles with 1HD-FTE – main tank 141 litres plus sub-tank of 45 litres. Full fuel also has to be included in the GVM.

Suspect, but not sure, that US-delivered 100 series came with 96 litre (25 US gallons) main tank -- seems low? And no sub-tank?

So, my guess is that the GVM allocated to the Australian IFS 100 series was a one-size-fits-all, intended to cover all the variants with one GVM, with some included allowance for the heavier variants. Maybe that is why the Australian GVM looks so different to the US GVWR.

The kerb weights published by Toyota (stock vehicle, full fuel, no persons, no load, no accessories, no fittings) for the Australian-delivered IFS 100 series variants range from 2,356 kilograms (5,183 pounds) to 2,735 kilograms (6,017 pounds) for the top-of-line model with all the trimmings. GVM is fixed so payload reduces to 525 kilograms (1,155 pounds) at the top-of-line model called ‘Sahara’ in Australia. Compliance is ‘challenging’ when armour, passengers and their gear are loaded!!

Maybe the main focus should be on the Toyota-recommended axle limits:
Front: 1,630 kilograms (3,594 pounds)
Rear : 1,950 kilograms (4,299 pounds)
Total : 3,580 kilograms (7,893 pounds)

Anyway, apologies for the trivia and to @ClassyJalopy for stealing his thread!!

The US (all of North America for that matter) only ever received one trim level of 100 Series, and as far as I am aware they all have that 6830lb GVWR. Their curb (kerb) weight may vary from year to year, but that GVWR has remained constant, which makes sense if the axles and chassis remain unchanged. The resultant curb weights of various years/trims may impact payload (different trim levels weigh more or less than others), but they shouldn't change the overall GVM/GVWR if the suspension, axles, and chassis remains unchanged.

The difference of the 1HD-FTE could be the big reason for the discrepancy, to try to accommodate some minimum payload that Toyota was aiming for. It's still interesting that US spec vehicles would be any different for gross weight, because trim and engine changes should only impact the curb weight (thus changing payload), not the GVM/GVWR. I'd assume that you could purchase essentially the same vehicle in Aus as you could in America, with the 2UZ, automatic gearbox, navigation, leather, electric everything, sunroof, etc, but you'd still have that 7172lb GVM, whereas we in the US would have a 6830lb GVWR. For reference, the listed curb weight of my 2003 is listed as 5360lbs.

Perhaps Australia's tolerance for payload is higher than what the US determines, or their formula for calculating it is different. It is my understanding that axles, suspension, and chassis remains unchanged in the US vehicle, so I'm speculating the discrepancy is how our respective countries calculate GVM/GVWR. Regardless, it's an interesting topic and helps back up my thinking that here in the US, the Land Cruiser is very underrated from a payload point of view.

I'm not saying we should all ignore US GVWR ratings and use the OZ ones instead, but it would suggest that we have a healthy safety margin when considering weight for our builds. Especially once you look at Toyota's recommendations.

Thanks for tolerating the BSing @ClassyJalopy, it's a really interesting topic.
 
AISIN rear height sensor arrived from Roack Auto. Quite encouragingly it even say Toyota on the part and the label has the correct Toyota part number 894007-60010.
Install was straight forward and barely took 15 minutes. All excited, I went for the test drive and noticed the ride is slightly less bumpy but still quite bad - like super uncomfortably bad! :poop:

So, slightly heart broken but I think the next step is to get the pressures lowered by re-indexing the torsion bars, swapping in LC springs and bleed the 4-6 liters of AHC fluid to see if I can get away without investing in new globes.
At what point does one say eff it, I am switching to conventional setup?

@suprarx7nut and @IndroCruise thanks for your help with sorting this out.


View attachment 2749189View attachment 2749190View attachment 2749191
Are you running a sensor lift? If so, what height are you at and are you using shock extension brackets?

Also, remind us, do you still have bubbles when flushing fluid out?

You've got a very heavy rig and I'm not surprised the King springs aren't enough. I think it's time for beefier springs and torsion bars if those aren't already swapped out.

Conventional switch? My typical line is "only if you have lines rusting apart". A decent swap will run you $2k and a weekend. That's a lot of time and $$ that could go towards AHC and likely result in a better ride quality when you're done. 🤷

*Oh, also should note, since you had 11 gradations, I think it's unlikely a dead globe. How old are the rear globes?
 

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