AHC / Springs / general questions for LX470 (1 Viewer)

[hskb]

Hi all - Newbie here.

I would like to ask if i should replace the rear springs and if so, what size and what brand should i get?
what other things i should consider when the back of the truck is getting heavier?


I got the 2000 lx470 with 275/65-18 tires half a year ago, and gradually update, build it up to be a camper/fun truck.
Added a 10" floating radio, an ironman 270 degree awning, an AirDowGearUp sleeping platform with 3" topper.
I am adding a medium Autohome Columbus Variant RT tent, and maybe a Gobi ladder for the rtt.


The AHC are original, and i just ordered 4 gloves for them. I plan to keep the AHC as long as possible.
Also the balljoints need to be replaced, my local shop quotes about only $300 difference between getting NEW arms, or just the balljoints only, so i am going with the 4 arms brand new.
Thanks for your help.

 

[GTV]

First you need Techstream to read your hydraulic pressures. Then you can adjust for weight.

 

[hskb]

oh, so i can just adjust the hydraulic pressures to compensate, no need to change the springs?

 

[GTV]

oh, so i can just adjust the hydraulic pressures to compensate, no need to change the springs?

The front torsion bars can be adjusted for free. The rear coils will likely need to be replaced but you need to know what your weight/pressures are first.

 

[jsloden]

Also, make sure the shop that's replacing the control arms uses toyota parts. If they're not, you would be better off just purchasing replacement bushings and ball joints and rebuilding the arms that are on there as long as they're not rusty.

 

[suprarx7nut]

Hi all - Newbie here.

I would like to ask if i should replace the rear springs and if so, what size and what brand should i get?
what other things i should consider when the back of the truck is getting heavier?


I got the 2000 lx470 with 275/65-18 tires half a year ago, and gradually update, build it up to be a camper/fun truck.
Added a 10" floating radio, an ironman 270 degree awning, an AirDowGearUp sleeping platform with 3" topper.
I am adding a medium Autohome Columbus Variant RT tent, and maybe a Gobi ladder for the rtt.


The AHC are original, and i just ordered 4 gloves for them. I plan to keep the AHC as long as possible.
Also the balljoints need to be replaced, my local shop quotes about only $300 difference between getting NEW arms, or just the balljoints only, so i am going with the 4 arms brand new.
Thanks for your help.

View attachment 3259462

View attachment 3259463

Good looking drawer system you have there.

For the AHC, you have to measure pressures before you make plans for anything.

The drawers weigh about what the factory third row seats weigh. The RTT and awning will be a bigger part of the equation. Once you know what you pressures are and what additional equipment you plan to add, you can select what springs and/or spacers you need. Without knowing pressures, you're just stabbing in the dark.

 

[uHu]

oh, so i can just adjust the hydraulic pressures to compensate, no need to change the springs?

Just to add on to what has been said above -- A direct answer to your question, the short answer is: No. The hydraulic pressures are for adjusting the height according to temporary, day to day changes, like an extra passenger or bag. Any permanent changes in weight has to be carried by the steel springs (coils, at the rear). The springs do wear out, so new springs are always better than old.
Looking at how you build is going ahead, I would guess that a set of King Springs might be needed. But a measurement of the current pressure and a calculation of the added weight will decide.

 

[hskb]

Thanks GTV, Jsloden, Suprarx7nut, and uHu.

i am reading the thread about the AHC by YotaMD now.
May look ahead for a pair of king springs.

 

[Seth7843]

You will not regret going with King Springs over OEM springs. They handle the additional weight you have added and will keep your pressures in spec.

 

[hskb]

Looks like quite a few members here using the king springs KTRS-79.
I see them available on ebay with shipping costs of $80.

is there some site in the US we can buy these? thanks
I need to do more reading, and decide rather sooner than later so that i can install them at the same time the arms are replaced.

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[IndroCruise]

Looks like quite a few members here using the king springs KTRS-79.
I see them available on ebay with shipping costs of $80.

is there some site in the US we can buy these? thanks
I need to do more reading, and decide rather sooner than later so that i can install them at the same time the arms are replaced.

Suggest best to explore local eBay in USA for the Australian-made KING KTRS-79 springs.

You may also want to try a direct inquiry to King Springs in Australia quoting the King Springs Part Number KTRS-79 and also mentioning the make (Lexus or Toyota), Model and Year of your vehicle. They should be able to tell you about distributors in USA, or Australian distributors who ship to USA:

Home - https://kingsprings.com.au/
Phone: +61 7 5539 6700
Fax: +61 7 5539 6881
For Australian Enquiries
E-mail: sales@kingsprings.com.au
For All Overseas Enquiries
E-mail: export@kingsprings.com.au
(Time difference: Noon on Tuesday at Kings Springs address is 6:00pm on Monday in California)


Amen to all previous posts suggesting a managed approach using measured AHC pressures as the starting point!!

There is little, if any, difference between the AHC and TEMS systems factory-fitted to all LX470 and to some LC100 models in various markets.

Here are some references which may be useful:

General Description of AHC and TEMS systems – includes diagrams and good explanations of how these systems are designed to work:

Go to LC100 Workshop Manual - https://lc100e.github.io/
Then on Index panel at LHS of the opening page, scroll down through the headings:
+ New Car Features
+ CHASSISS
+ Suspension
+ Active Height Control Suspension and Skyhook TEMS

At this 20 page extract, see guidance on AHC load limits described for stock vehicle at the foot of Page 197.


AHC and TEMS Diagnostics
Go to LC100 Workshop Manual - https://lc100e.github.io/
Then on Index panel at LHS of the opening page, scroll down through the headings:
+ Repair Manual
+ DIAGNOSTICS
+ ACTIVE HEIGHT CONTROL SUSPENSION & SKYHOOK TEMS

To get real benefit out of this section requires some software and a cable connector together called “Techstream” -- or some other scanner capable of reading the Suspension Electronic Control Unit (ECU). This enables use of information in this section relating to the “Toyota/Lexus hand held tester”.

Reference: How-To: TechStream In 5 Minutes - https://forum.ih8mud.com/threads/how-to-techstream-in-5-minutes.1034923/#post-11416736


AHC and TEMS Adjustments and Repairs – includes Specifications for Pressures and Other Details, Component Repairs
Go to LC100 Workshop Manual - https://lc100e.github.io/
Then on Index panel at LHS of the opening page, scroll down through the headings:
+ Repair Manual
+ SUSPENSION AND AXLE
+ ACTIVE HEIGHT CONTROL SYSTEM
+ BLEEDING
+ ON-VEHICLE INSPECTION – includes specified AHC pressure ranges and other details
+ LOCATION
+ ADJUSTMENT
+ other related headings

Searches on IH8MUD will reveal many threads relating to the Active Height Control (AHC) and Toyota Electronic Modulated Suspension (TEMS) as fitted to LX470 since 1998 and also fitted to LC100 in some markets in some years.

Two good starting points are:

Thread initiated by IH8MUD Member @LndXrsr:
The ABCs of AHC - How to Measure, Flush, and Adjust all in one place - https://forum.ih8mud.com/threads/the-abcs-of-ahc-how-to-measure-flush-and-adjust-all-in-one-place.1211999/#post-13116520

The excellent video and “cheat sheet” produced by IH8MUD Member @suprarx7nut:
AHC Info - https://www.yotamd.com/blogs/news/ahc-info

 

[hskb]

Thank you very much IndroCruise for your advices, and lot of good references.

 

[hskb]

so i figured the car is 23 yrs old and the springs need to be replaced, so I go with the king springs KTRS-79, and ARB OME80PR10 Old Man Emu 10mm bushing (same yellow color ) for the left spring.
Amazon product ASIN B004P9T9F4
will need to read up on tech-stream.
thanks

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