My 04 rx330 AWD has 143k miles and am the original owner. It is well maintained and due to the miles decided to purchase KYB struts with mounts and boots. I took it this morning to an independent shop for installation and after his inspection, he said that struts have no leaks and does not need to be replaced. I do not have any issues re the ride at the moment . I will be using this now as my DD since Mrs has a new car and my other DD is a lifted GX470 with new suspension so this Rx suspension feels soft. Mechanic can't do the install till next week so he said that it might last another 20000 miles. Should I just go ahead or save the money for later. Thanks for your replies

 

There really isn't any exact specific time (or miles) that you should replace struts/shocks. It depends on how many times the strut has extended and compressed and how violent the conditions were, i.e., potholes vs gentle dips. The internal seals wear out and the strut looses its shock absorbing/dampening ability. This happens slowly and you don't notice it as a result. To say that a strut or shock is good because it is not leaking is totally wrong. At 143K miles, you will notice a definite difference in the car ride if you replace the struts.

 

According to CarFax, the front struts were replaced on my '05 at 116k miles. The rear struts are needing replaced now (132k miles), as I can feel some extra bounce/dipping, especially coming from the right rear, and I still have some knocking noises coming from that side, as well. It sounds like it's coming from the top of the strut, but can't be 100% sure. I already replaced the sway bar links and bushings, which helped a lot, but didn't solve the noise. Mine spent nearly its whole life in PA, with potholes everywhere, so there's no shame in the struts being bad. I'll probably invest in new carrier bushings, too, at least for the right side, if new struts don't solve the noise issue.

 

Since the front struts were replaced less than 30K ago, they should be fine. From what you say, you might have a rear strut that is blown, but that shouldn't create a noise, but anything is possible. You might want to check that the exhaust pipe is mounted solidly and isn't hitting anything.

 

I thought about the exhaust. The only problem with that is it only makes noise when the right side hits a bump, so it's isolated to right rear wheel impact. It has to be something either strut or possibly carrier bushing related.

 

Hitting a bump is exactly when a loose exhaust system would bounce around and come in contact with something. Have the exhaust hangers checked that they are not broken, missing or weak. Don't rule it out so quickly.

 

If that were the case, wouldn't it be noisy no matter which side hits? I'd think any disturbance across the whole rear end would cause the exhaust to shift if it were loose. I'll try to check in the next day or so, after the temps get a little closer to the freezing point or warmer.

 

You can't say that a rattle will only occur under specific conditions. With the exhaust, it all depends on how loose it has become. Since the exhaust is on the right side of the car, it will start out making noise when the impact force is close to the weak area. But as it gets looser, it might rattle when you slam the driver's door.

I'm just trying to make a suggestion. It's easy enough to check out. When you are trying to track down noises, don't rule anything out.

 

Good point. I might be able to get under it today, since the temp will be in the low 40º range.

 

update.
Installed the KYB and been driving it for the last 2 weeks. I did not notice any significant improvement in the handling and ride of the RX. It now rides firm which can be taken as a loss in the qualitynof the ride. The mechanic was right that my original struts was still in good condition. So to save some money which was $1200 includes labor and alignment, only replace it when there is a need for it. On a positive note, I have an RX that will give me more years of service and avoiding those monthly payments

 

Agreed, only replace parts when needed in order to "Just Say No" to monthly payments.

 

I have noises that sound like basketballs bouncing when I hit certain bumps, exhaust and spare are secure. Will have to have someone check struts?

 

Wouldn't hurt to have them checked, but it could be a few things making noise.

Rear sway bar links and bushings - I replaced all of that, which helped a lot, but didn't solve the issue.
Axle carrier bushings are very possible - in laymen's terms, they're the outer control arm bushings that attach to the wheel "knuckle" that holds the hub assembly. I'm suspecting that's where my noise is still coming from, but I haven't had the chance to check them. They also play a part in higher speed stability of the rear end, which I'm suspecting I have a slight issue there, as well.
Lastly, maybe struts or strut mounts.
Or, quite possibly as mentioned above, weak/loose exhaust hangers.

I did find a youtube video talking about the technique needed to check the carrier bushings ("knuckle"), but the mechanic also said the bushings can't be purchased alone, and the whole carrier needs replaced, which is not accurate. Somewhere on here I found a thread talking about them, and there was a Toyota part number listed, which I found on eBay for around $33 each. Of course, I didn't subscribe or put the bushings on my eBay watch list...

 

Good info thanks

 

A little update. After seeing the thread talking about the hatch making noise, I decided to dig around a little back there. I wrapped electrical tape around the hook, then decided I'd pull the trim to see if there was easy access to the little trim flap that surrounds it, which lead to taking out the rear-most compartment. Upon removal, I discovered my missing jack was just laying back there, the tire iron was laying underneath the rear compartment, and I found the spare tire bolt while I was in there. Seems odd you'd have to remove the compartment to get to the spare bolt, but we all know Lexus does some odd things sometimes. Then I reached under to see if the spare had any play. Sure enough, it did, so I tightened it up. I tried wiggling the exhaust, but it appears secure.

After finding all of those potential noise makers, I was eager to take it for a drive... nope... still have the knocking noise, although overall noises are less. So, that brings me back to thinking it's either strut related, or the axle carrier bushings... the saga continues.