UZZ32 Active Valve Body Reseal - Written by Peter Scott at Planet Soarer October 2003

I resealed my UZZ32 Active Valve body hoping to eliminate a high speed right hand corner bounce - no luck. BUT the reseal did do two things:

  1. No more sag when the car is parked .

  2. Car smoothly adjusts height when at stop lights - no more sudden suspension movements.

So these two things alone made it worthwhile for me.
Stay tuned for front shock rebuild and further sensor swaps.
Disconnecting boot sensor removes bounce and makes car softer - but an error message is displayed on dash.

Here's some bounce theories that I was faced with:

A. The valve body (front passenger fender) needs a reseal. Seals leak, letting pressure out of shock, shock pumps itself up again, leaks out, pumps up etc etc. There is a seal kit listed for $70 in parts CD - I have this kit and will attempt open heart surgery on Active this weekend. Kit consists of 20 or so o-rings - funny sizes etc - Toyota Japan agreed to manufacture this kit for me - took about 8 weeks. (NO THIS DIDN'T FIX IT)

B. Bottom part of shock - the sealed pressure part is stuffed. Don't know how it works - but new ones are available for 400 or 700 bucks - forget which. A seal kit for $120 for top half and a new bottom half gives a new shock that isn't that expensive. BUT what does the bottom sealed part of the shock do? and how do you know if it's stuffed and what would it affect?

C. Nitrogen accumulator is stuffed. No idea what this is or what it means. I can guess, but I don't KNOW.

My car has a bounce only through right hand bends with very high g-force. It is not speed related - only g-force sets it off. Only notice it on racetrack or driving with Rob Hayden (same thing really!). Left hand bends it is perfect. A real pain at Mallala and Phillip Island - my exhaust has bounced off!

My bounce is affected by the grip of surfaces and tyres. Race tyres on dry track give maximum violent bounce. Kumho's 265's street tyres on damp road exhibit no bounce. Others have also reported certain tyres affect on bounce. Pirelli PZero comp 235/45/17 inch tyres didn't bounce like my 225/50/16 540s semi slick tyres.

Bleeding the individual struts didn't affect my bounce. Only Rob Hayden and racetrack guys will ever feel my bounce - it doesn't exist during normal or spirited street driving - only "racing".

So grip levels and g-force affect my bounce the most. The car has always had this. Nothing I have done has affected the bounce. At Mallala I had to change driving style, slow in and spin tyres out to stop bounce - I couldn't corner at maximum g's for fear of bounce.

At Phillip Island, the corner onto the main straight is a lefty - perfect - but right hander at 200 kph at end of straight is uncomfortable and Honda corner is violent. The rest of track is ok. MG right is ok, but I expect this is due to the slow speed of the corner.

So there you go.

If anyone knows or has any theories I'd like to hear them.

Like what does the sealed bottom part of the Active shock do?
Pictures of exploded shock are here:

Could it be some g-force sensor stuffing up?
Why only right hand bends?
Why do some Actives have slow speed, speed hump bounces (not mine)?
What lets pressure out of shock?
Is it some feedback loop?
Could it be electrical (sensor?) or hydraulic seal?

Rebuilding top half of shock didn't fix it.
Bleeding it didn't fix it.

Given the problems that I was having and that I was able to procure a rebuild kit for the valve body from Toyota, I thought I'd give it a go anyway. I referred to Jeff Harper's 'Soarer Bible' to assist me with the task.

The text said to tighten the Allen screws at the top of each strut to lock the suspension - this is
to stop it collapsing when you removed the lines from the valve body.

There were also several warnings about only working on the valve body in a clean room. No fibre gloves. NO rags. Bare hands or clean rubber gloves with no powder. No compressed air. Natural air dry only.

I had to bag up and wire tie all of the lines as they were undone. I made a special service tool out of some bookcase mounts.
Need to make another one to remove the filter somehow.

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The valve body is spotless inside. BUT the old 'o' rings that I am replacing are squared off - you can see it with the naked eye - they are worn for sure.
So there's hope that the Toyota Valve Body Overhaul Kit will do the trick.

The filter is stainless steel mesh - washable - never need to buy another - explains it's $350 price tag a bit.
The filter did have some crud in it - looked like little bits of metal - clean shiny aluminium- not much - the rest was spotless.

I didn't use the seal for the pressure sensor off the side of the filter -looks like it just sends warnings if
pressure gets too low. - or the four little o-rings for the other mystery bits. It just didn't seem important on inspection.

I rang James at Castle Hill Toyota and asked for the overhaul kit for the UZZ32 valve body and he did the rest. It's an official Toyota Kit. I also ordered sufficient active fluid to flush the system and recharge the valve body.

Changing the seals was easy, bumper removal was easy, removing the valve body was ok. The holding bracket was easy.
Keeping everything clean is a pain.

Figuring out what to do, wondering what everything is for, that's the tough bit - it's coming together though.
It doesn't seem so hard at all now that it's nearly done. I was dreading it. Same as the shock rebuild.
I just hope it starts, bleeds, runs and works now. It's open heart surgery on an Active.

Special tools were replaced with bookshelf brackets to hold body on vice.
The filter removal tool was just two screwdrivers and a spanner - it's not that tight and o-ring seals it.
So although it wasn't a hard job - there looks to be plenty that can go wrong, some high risk stuff.
And it's not even going yet and who knows if the problem will be fixed.

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Picture of the old and new o-rings - top one has squared off.

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Stainless steel filter before cleaning.

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One of the 5 valves removed from the body.

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The job starts by setting the car on stands.

The bumper has to come off for sure to give simple access to the valve body which is under the passenger side headlight, forward of the front wheel.

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Plastic bags and wire ties for every line.

In taking the bumper off and removing the valve body I would have been lost without the workshop manual in English and Japanese.
You will need a copy for sure - the workshop manual is the best thing to have for your Soarer.

Even if you don't work on the car yourself you can print out the pages and hand them to your mechanic.
I wouldn't attempt this without the manual.

The impression I got from Toyota Japan was that no-one had ever asked for a seal kit before ever.
They agreed to manufacture one for me - estimated 10 days stretched to nearly 2 months. But I don't know for sure what the situation is.

Sometimes I get the impression that because of depreciation in Japan and high cost of repairs, the 32 didn't get fixed much.
Then once exported no-one knows how or what to do so they still don't get fixed much.
Hence I lot of 32's limping around wounded - which is a real shame.

It would be great to talk to a Japanese Toyota Mechanic who has that official "Toyota UZZ32 Service Technician" certificate on the wall and ask what does cause bounce, what are common problems and fixes etc - but what are the chances of that?
Do Toyota Japan still service and repair UZZ32's? I don't know.

So the result after all this work - No change. The car drives the same as before I reckon.
The high speed right hand corner bounce is exactly the same. Normal ride I didn't really pay attention.

So on my car, resealing the valve body made no difference to high speed bounce around right hand corners. Left hand corners are still a dream.

Part number for seal kit is 04490-24011

List price $85, Net $59.09, GST 6.53, freight 6.20 total of $71.80.
Call James at Castle Hill Toyota 02 9680 2233