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Lexus Owners Club > Lexus Models > LS 400 / Lexus LS430 / Lexus LS460 / Lexus 600h Club > Brakes & Suspension
lexusn1ce
hi i have an ls400 1992, and wanted to ask about the lower rear suspension arms, as mine seem to be very rusty but still strong, do these normaly fail due to rust or is it normal? i dont have any knocks etc from the rear its just the rusty arms and i cant find these anywhere online so not sure if i have the right name its the box section bar that links the rear hub to the middle of the cars chassis any one who knows about this ?

also i get i slight very occasional (sometimes not for weeks) knock when turning and braking at the same time from the front only does it once, and also the other moving arms seem to be very rusty, so i was wondering if anyone knows where to obtain these for a reasonable price or can the balls be replaced on their own.

if i am being ott and these parts are ok rusty please let be know, the last thing is on the underneath of the car just infront of the right rear wheel arch there is a patch of rust not very penetrating but its there none the less and is it something to worry about. has anyone else noticed this on theirs the body is mint so finding this when i was in the pit was quite annoying its on both sides but you cant see it on the other side because its covered.

any help appreciated
SteveLS400
[quote name='lexusn1ce' date='26 May 2010 - 05:39 PM' timestamp='1274891964' post='721483']
hi i have an ls400 1992, and wanted to ask about the lower rear suspension arms, as mine seem to be very rusty but still strong, do these normaly fail due to rust or is it normal? i dont have any knocks etc from the rear its just the rusty arms and i cant find these anywhere online so not sure if i have the right name its the box section bar that links the rear hub to the middle of the cars chassis any one who knows about this ?

also i get i slight very occasional (sometimes not for weeks) knock when turning and braking at the same time from the front only does it once, and also the other moving arms seem to be very rusty, so i was wondering if anyone knows where to obtain these for a reasonable price or can the balls be replaced on their own.

if i am being ott and these parts are ok rusty please let be know, the last thing is on the underneath of the car just infront of the right rear wheel arch there is a patch of rust not very penetrating but its there none the less and is it something to worry about. has anyone else noticed this on theirs the body is mint so finding this when i was in the pit was quite annoying its on both sides but you cant see it on the other side because its covered.

any help appreciated
[/quote]

The general answer is , yes, I think you are OTT on the issue of rusty suspension components. My own are rusty again but it just passed its MOT so I would only worry if yours has an issue at that time. I am going to reapply Waxoyl to mine after wire brushing any loose stuff away.

Similarly, the application of Waxoyl to the area infront of the wheel arch should suffice. Do not use a wire brush here or any where else that is factory undersealed. Whilst you are down there, dont forget to do the lower lip of the sills.

With regard to the front suspension, the balls may not be able to be replaced on their own, depending on the component. Again, my advice is to wait for an MOT fail.

The knocks and squeaks are a known fault. If you have a look on fleabay >Vehicle Parts & Accessories>Lexus LS400 you will find replacements. However, if you give the rubbers a soaking with WD40, it should cure the problem for a time. I did mine last weekend as mine only creaks when the weather is warm. Of course, increasing the volume on the Lexus Premium Sound System renders this obsolete.

Hope that helps/reassures.
Malc
[quote name='lexusn1ce' date='26 May 2010 - 04:39 PM' timestamp='1274891964' post='721483']
hi i have an ls400 1992, and wanted to ask about the lower rear suspension arms, as mine seem to be very rusty but still strong, do these normaly fail due to rust or is it normal? i dont have any knocks etc from the rear its just the rusty arms and i cant find these anywhere online so not sure if i have the right name its the box section bar that links the rear hub to the middle of the cars chassis any one who knows about this ?

also i get i slight very occasional (sometimes not for weeks) knock when turning and braking at the same time from the front only does it once, and also the other moving arms seem to be very rusty, so i was wondering if anyone knows where to obtain these for a reasonable price or can the balls be replaced on their own.

if i am being ott and these parts are ok rusty please let be know, the last thing is on the underneath of the car just infront of the right rear wheel arch there is a patch of rust not very penetrating but its there none the less and is it something to worry about. has anyone else noticed this on theirs the body is mint so finding this when i was in the pit was quite annoying its on both sides but you cant see it on the other side because its covered.

any help appreciated
[/quote]

Think it's good advice to wait for an MOT before you start to get worried about these things !

I'm thinking that if you don't do a huge mileage every year then you will get plenty of pre-warning with an MOT Advisory .......... then some more time to save up for the jobs to be done !

Metal and wet weather ...... things go a rusty colour .... lots of difference betwen that and penetrating rust methinks !

I don't think the LS400 is prone to debilitating rust ..... no one's mentioned it before on here to my knowledge although I have been reading of doors having to be replaced under the 12 year warranty on the LS430's due to rust penetration ........ but NOT on the LS400 so far.

Just de-stress a little and enjoy !

Malc
lexusn1ce
thanks to both of the members above thats put my mind at rest because it has passed an mot couple of months ago before i bought it so if i get som warning that would be good given the cost of repair
Malc
[quote name='lexusn1ce' date='27 May 2010 - 08:28 AM' timestamp='1274948930' post='721540']
thanks to both of the members above thats put my mind at rest because it has passed an mot couple of months ago before i bought it so if i get som warning that would be good given the cost of repair
[/quote]

What I would keep an eye on tho' is the PAS unit and any leaking of the fluid. On your model ( my earlier car was a 1992 ) the PAS is directly above the alternator and when the PAS leaks ( as they always eventually do, until the seals are re-done ) the alternator might be " knocked out ". And that's expensive.

Have you any history on the car ?

Malc
lexusn1ce
i have full history up to when i bought it and it has 1 owner from new and i did a full service when i got it too.
The pas and alternator has just been done because it went begining of this week its in another post on here the only other minor probs im aware of is the float is weeping on the water res, the pas cooling pipe is rusty but not leaking yet and a slight blow on egr pipe which im gonna leave bexause i can hardly hear it.

So at the moment i think its ok.
bazgtr
also i get i slight very occasional (sometimes not for weeks) knock when turning and braking at the same time from the front only does it once, and also the other moving arms seem to be very rusty, so i was wondering if anyone knows where to obtain these for a reasonable price or can the balls be replaced on their own.


The noise above braking and turning is proberly your top arm locking nut is lose on the one side.

Just tighten both up a little and see if that helps. You can do it on the road. The nut is just above the top of the tyre when you look in.
steve2006
That's interesting as mine does this knocking as well only when there is lock on the steering either direction and the brakes are also applied, I always thought it was brake calliper movement as if you take your foot off the brakes the noise doesn't occur.
The brakes are serviced every 6000 miles and I have never found a problem with the callipers apart from a sliding pin seized once which was replaced
It's done this for over 3 years but has never failed an MOT or received even an advisory.
I would like to find the actual cause so will check the upper arm retaining nut as suggested.
bazgtr
[quote name='steve2006' date='31 May 2010 - 07:37 PM' timestamp='1275331079' post='721935']
That's interesting as mine does this knocking as well only when there is lock on the steering either direction and the brakes are also applied, I always thought it was brake calliper movement as if you take your foot off the brakes the noise doesn't occur.
The brakes are serviced every 6000 miles and I have never found a problem with the callipers apart from a sliding pin seized once which was replaced
It's done this for over 3 years but has never failed an MOT or received even an advisory.
I would like to find the actual cause so will check the upper arm retaining nut as suggested.
[/quote]


Steve just give it a little turn to see if that helps. You'll find it's ok for a few trips but then starts again.

The nut is as they say a nats manhood of a gap. It will never fail or fail as an MOT inspection but onlt if the ball joint has play up and down. The gap in question is not enough to cause this failure. I've seen loads over the years.

You can get new arms but I find they never sit like the orignals and cause the same problem as the case when fitting new ones on my own car. I just put up with it. There are two more solid cures, but that involes a little more work, But it's just not worth the day doing it when you can just tweek the nut every few months in 30secs.

Let me know if that was the problem for you.


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