Anyone Have A Fail Air Shock/strut Lying Around?

[ChrisKaye]

Hi all,

I've been investigating alternatives to purchasing air shocks/struts/bags individually from Lexus at between £700-800 each!

Now I've found many suppliers of components but no-one that makes an aftermarket unit or it's constituent components specifically for the RX.

Ideally, I'd like to get a failed sacrificial unit to strip down, measure the air bag and shock damper to see if I can contact good suppliers directly (Dunlop, Bridgestone, KYB etc.) and hopefully make a DIY refurb guide.

Unfortunately I'm not made of money but would be willing to buy a failed rear unit if anyone has one in their garage?

From what I can ascertain, the front units are different air bag "types" to the so there would have to be 2 guides.

On a positive note, many people state the system is scary and complicated - before my research started I would have been inclined to agree but the more I learn, the more I see how simple the setups are!

The big problems are lack of decent RX information and suppliers.

Full aftermarket air strut kits (ie: 2 x Front, 2 x Rear units) for the RX are available at £1200 BUT before leaping into the unknown, I'd like to see if a refurb of the Lexus/Toyota parts are possible to keep things as stock as is possible.

If anyone can provide further info, ie: front and rear air bag dimensions, types and if at all possible the original manufacturer (as Toyota/Lexus don't make air bags!) then that would be really useful.

Thanks all,

Chris

[The-Acre]

I think it would be amazing to discover that air shocks can be rebuilt. I hope you manage to do this and that you source one OK. Unfortunately the eBay ones tend to be around £130. Maybe if you don't have any success from a member you could try a breakers, pointing out that it doesn't need to be a working unti?

[ChrisKaye]

Yeah, I have seen only a couple on eBay at the moment £250-350 but some look very scabby for the money and as most are getting to 8-10 yrs old, I'm sure they wouldn't last long fitted to an RX as a replacement. Also have the air holes to the bags open to the elements will be letting damp air in which is a bad thing from what I have learnt.

I keep making offers upto £50 in the hope one of the sellers gets fed up advertising/holding out for big money. As soon as I have news I'll be on here to keep you all up to date!

On another positive note, I've been designing a new housing (mainly replicating the Lexus part) for the height sensors so they can be "printed" using a 3D printer :)

This should bring the price of a replacement down to £50 each or lower!

[mikesands]

I can't help with the original question but can I ask if RX owners do experience substantial problems with air suspension. It cost me a fortune on my LS430

so I went for a standard sprung RX400H

Mike

[ChrisKaye]

Hi Mike,

I suppose it's a similar question to what put me off the 400h, but instead of air suspension, the thought of a hybrid problem gave me the heebyjeebies...!

Chris

[ColinBarber]

I can't help with the original question but can I ask if RX owners do experience substantial problems with air suspension. It cost me a fortune on my LS430

so I went for a standard sprung RX400H

Mike

Yes they are a problem on the RX as well.

[ChrisKaye]

I think all air setups will wear over time (just like normal shocks & springs) but have more components and most bits are very expensive to replace.

I think trouble is most mechanics, including the Lex dealers, are a bit clueless when it comes to fault finding air suspension issues and like to replace multiple bits hoping to eventually stumble across the failed part at some point (or until customer can't afford the "fault finding" process any more!)

I know mine is currently giving message c1751 in an error code which means something like "compressor circuit continuous current".

So, let's swap out the air compressor for £1300, eh? Simple fix or so it would seem?

When I reset the code, the compressor and solenoids work fine! Odd that!

So, what could the cause be then?

When looking at each air strut, I had one that loses air almost as quick as it is put in by the compressor (most likely a split/tear in the air bag on the strut now it's 12yrs old and 108k miles use).

This causes the air compressor to be run longer than it's programmed "safe" value of 99seconds (to protect it from overheating and breaking, good job when they are that expensive!) and log the c1751 error. The suspension computer then disables the air system for 10 mins or 3 engine starts, warm ups and then shut downs, before re-enabling the system to see if the fault remains (weird terrain and other issues may have caused the error rather than something breaking/wearing out). If the fault persists, the air system is then disabled for 70mins of continuous driving or another 3 start/warm up/shutdown cycles.

As all of my struts are not currently holding the air pumped into them, the compressor doesn't get a signal from each wheel height controller to the compressor saying "I have enough air thanks, I don't need any more, you can turn off now", the poor compressor stays on until the computer freaks out at the 99 second count and shuts it off.

My current frustration is sourcing replacement air bags for the struts. A £100 repair for almost all air suspension cars except my RX as Lex will only sell the whole strut (which includes strut tower, shock absorber and air bag) for £600-800 depending whether front or rear (fronts cost more)... I haven't found out who makes the bag component for Lexus struts so can't source a replacement that way (yet, maybe!) but a lot of household name companies (Bridgestone, Dunlop, Firestone etc) make air bags...

The above also holds true if your air bags are fine and a shock absorber has failed (leading to ride problems) - the shock absorber cartridge or whatever you call it on a normal car setup would just be replaced for a few quid, but on the air suspension the KYB shock part/model is not listed, so you've guessed it, gotta replace the whole air strut! (Hey, at least I know KYB make it, so there is some hope!!)

Sorry if I have bored you all!

Chris.

[ChrisKaye]

So, after many hours over a few weeks, I've found the following pics on a Russian website (2drive(blocked word), I believe).

The following are the only pictures of air struts I have been able to find to show the anatomy of the components.

Toyota will sell (as separate items) the two rubber components that fail/perish over time and miles, a rubber "cover" and a "rolling sleeve diaphragm" both parts sourced together are approx £150 per corner.

There was a lot of debate about how to affix the replace the rubbers as it appears the lower (and possibly upper) ends of the rubber sleeve are crimped and/or bonded onto the strut itself. Unfortunately comrades, my Russian sucks!!

Here are the pics (most likely for the first time on an English/US website!):

[ChrisKaye]

Here are the replacement new parts (also includes the "cable ties" that secures the big rubber/plastic accordion style over dirt/dust boot/shield)...

[billgatesisaconman]

Are the new "cable ties" metal Chis ? ... can't tell from the picture....

[ChrisKaye]

Nope, still black plastic!

When I had a look on mine, you can use a screwdriver to release them and re-use as required.

[ChrisKaye]

Also I found out the original manufacturer is a company called Tokico, but you guessed it, they don't sell the struts or bags for the RX to the public! Humph!

Still not been able to source a secondhand strut to experiment with and knowing a little more of what is involved, I won't be stripping mine just yet...

I did find another image of an owner who'd chopped the top off of their air strut and replaced with an air sleeve that cost £60!

The real beauty of this approach is that he can now strip the whole unit down to the shock absorber and replace it should he ever need to in the future. Genius!

[stringbender]

As the owner of a 10 year old SE L I know that big bills lay ahead for the air suspension system. Years and years ago someone posted about replacing the compressor and pipes (?) himself for very little outlay. He sounded like a genius to me and so do you Chris. I like a tinker but this is deeply serious stuff here. Thanks for all the detail in the posts.

Alan

[ChrisKaye]

Woo-hoo!

Found some struts to experiment with and should be here tomorrow... Will have some movement on this post very soon! :)

[ChrisKaye]

Right so an update for those interested!

Everything bolt wise and chassis wise on the Lexus RX is made from cheese (and not the good kind).

My conclusions from refurbing a not so bad second hand air strut is that the struts don't fail easily and the design (if expensive) is actually very sound.

The element that lets it down, is not the actual air bellow/Spring/bag but the metal or lack of treatment that causes the strut to disintegrate over time.

First, let me scare you a little if you have a 10+ yr old RX SE-L (see pics) this can only be attributable to a part designed deliberately to fail once it hits a certain age. Decent treatment or paint could have avoided this! My original strut (offside rear)...

[ChrisKaye]

And now to the refurbed part, thanks Gary in Wales for eBaying them due to a failed compressor!

Before beginning the refurb, order some more plastic air tube clips from the dealer - you cannot reuse this part! See my previous post on using an A/C / Fuel Hose removal tool to get the old air line out. Also, make sure you have some spare stainless steel bolts available, you will most likely break or strip the head on them when removing!

The OEM drop/stabiliser links also suck as they use a hex bit to stop the screw thread rotating, you will most likely have one end strip on you and end up cutting off the bolt, thereby requiring a new drop link (£12 online).

I am lucky enough to have a compressor, these makes leak testing the new/second hand/old struts easier but you can fabricate an adaptor and use a bicycle pump if need be...

Beginning the refurb:

Tape off the air inlet to the strut.

Stand the strut up on a table and remove the outer "accordion" style rubber cover from the strut by sliding it down and over the large plate half-way down the strut leg, be gentle removing the large cable ties, a blast of compressed air can clear the locking ends of dirt so a small screwdriver can release the latch holding the tie on. These bits are expensive from dealer, if you have to replace them, source from eBay/Amazon - they aren't special just normal extra long cable ties!

There is a rubber collar around the top of the strut that won't come off, with some warm soapy water and a washing up sponge that has a plastic scourer, clean the collar of impregnated rust, then fold it back in on itself, in half and let it rest on the plate, out of your way.

Using a wire brush and sanding flap wheel drill attachments, remove all loose rust, including rolling up the air bag and getting all the rust underneath it off the piston that the bag rolls over, and also from the metal chamber at the top of the strut.

Some parts of the rust/dirt can be fairly thick, a gentle tap with a light hammer and a sacrificial screwdriver will loosen this surface layer before wire brushing/sanding can help!

At the top of the strut, there is a lip that protrudes at the bottom of the air chamber, make sure all loose and sharp rust is removed without taking too much of the lip/edge off.

Roll the air bag back up the strut from the middle of the strut leg until you see the metal swaged collar that holds it to the air piston.

Remove all loose and surface rust around the piston, then thoroughly clean the impregnated rust from the air bag using a sponge and warm/hot soapy water, this takes the most elbow grease!!! Dry all parts thoroughly with an old tea towel.

Using a small hand wire brush, remove surface rust from the large plate around the middle of the strut.

Mask up the air bag and give the strut several coats of spray "direct to rust" Hammerite gloss style paint - leave overnight to dry somewhere warm-ish.

Once paint is dry, use silicone spray/lubricant on the air bag, spray liberally, then rub in with a cloth, then give it a light misting.

Start at bottom the the air bag where the metal swaged collar is located, lube it, then roll it down in stages luring as you go until it is rolled over the piston.

Use silicone spray on the rubber collar that you folded over on itself earlier, making sure you get both sides and slide it back up the strut and half over the lip on the air chamber.

Wash the "accordion" style outer rubber cover, inside and out, the clean/lubricate once dry with more silicone spray and a rag, wait until you fit it back onto the strut before spraying silicone on the outside of the cover as it will be slippy and difficult to grip!

Reattach the cable ties.

Unplug air tube, and GENTLY clean the rust from the outer and inner edges. You can take out the White/clear plastic clip with the two teeth on it, we don't want rust getting inside the bag. A cloth, prodder and more silicone spray can help to clean in the hole but don't damage/bash/gouge the little rubber o-rings inside. I had the parts to replace these but was worried that dirt or rust may be loosened and stick to the new o-rings and lead to air leaks (besides if I have an air leak as I didn't change them, I still have the bits!)

If you are fitting this refurbed strut within a few hours to your car, then remember to clean your air hose of any loose dirt with a rag and more silicone spray then tape it off to keep it clean, put some white grease on the new plastic "2 tooth" clip n the side facing the o-rings and gently edge the clip into the air tube on the strut, using a small screwdriver to keep it neat and lined up.

When ready to pop the air hose into the strut, gently wipe it with a bit of white grease before sliding it in, where you will feel/hear the plastic clip lock onto it.

If not fitting the strut to the car for a day or more, tape the air hole up. The bag doesn't like moisture inside it!

[ChrisKaye]

More pics, after painting & siliconing...

Bear in mind that these struts were only half as bad as the ones from my car and if yours are as bad as the ones I removed a few posts back in this thread, then I would recommend they are beyond refurbishing due to the sheer amount of metal you will have lost due to the infernal rust...

However, this whole project for me was just to tide me over until I concoct a way of rebuilding the strut using some of the original OEM strut and aftermarket "bag over strut" air bags, so stay tuned!

[PCM]

Just - WOW!

[ChrisKaye]

Yep, it's a heck of a difference Piers, and it is so nice not bottoming out on pot-holes and drain lids again!

It cost about £10 a corner/strut to do this, and about 2 hours of time per strut including removing the old one and fitting the refurbed unit.

The second hand struts cost me £450 inc. shipping for all 4, in the end!

None of the bags on any of the struts (including my nasty looking old one) have holes or look worn (at least externally) - I think my old one failed as the rust killed so much metal at the top of the strut where the bag is joined, that air was gushing out.

I will check the old unit for leaks with soapy water to see if my suspicion is confirmed!

[scottishv8owner]

I just about to replace my front left air shock on my rx300. Its not due to a leak, but the internal upper shock mount which has gone (73k). Its a ridiculous design fault that these cannot be changed as they can be on a 'normal' coilover!

I did mange to get a discount from the local dealer, but the part still cost me nearly 700 quid :shutit:

P.S. I wonder how many have been changed as a result of the crazy 'push in' plastic connector at the top of the shock underneath the plastic cover? such a cheap design!

[ChrisKaye]

Damn, it's a shame you didn't speak up a week ago as I have 2 front struts here with mounts!

I haven't refurbed/stripped them yet but you could have had a top mount (assuming you can remove them from the strut!) for a lot less than a whole new strut!

If they are removable, I may see if I can source a replacement to bearing so I have this up my sleeve for the future (or anyone else in your predicament)...

Chris.

[ChrisKaye]

Here's a useful link (whilst it's still working) for the service manual pages to replace the front strut for those interested:

http://www.justanswer.com/lexus/7lr7c-lexus-rx-330-trying-change-strut-mounts-realized.html

[Timeboy]

hi been working on my front strut nothing wrong with airbag or operation all good my top mount moves a good few millimetres making quite a bang clearing worn out on bearing don't know if these are available separate ordinary top mount about £50 but tell me there not for the air models

secondly I brought tool to remove air pipe only pushed so hard it broke without moving one bit I assume air in strut stopped it from pushing down any idea how to release air and are this pipes able to be joined should they split in process had is stuck hanging on pipe for couple weeks now

[ChrisKaye]

You could join the pipe with 5mm push to connect fittings (look on eBay) - if you are thinking of cutting it off, get an air line cutter too so you don't cut at an angle.

When the strut s off, try and salvage the original pipe into the strut as it has a collar to stop it popping out of the strut.

The little clamps (clear, in the picture) are silly money from Toyota, but I'll pop a spare one I have in the post for you if you need it, they only work on the rear struts tho! PM me with your details.

[Timeboy]

hi

ok many thanks for all this

will see if I can get out again before I go cutting and joining would like to get off complete

will let you know

not sure if air pressure stops it pushing in as well