Lexus LS 430 Suspension and Drivetrain

lucian95

I bought LS430 in 02 and currently it has 106K miles on the odometer. I hope somebody could offer some advice to my question: I recently noticed, during my regular highway commute, a sound consistent with a tire being slightly out of balance or perhaps having a flat spot. It's coming from the rear. I checked with a tire place and they couldn't find anything wrong with tires, but they said I'll have to live with it until the next replacement (Toyo Proxes TPT with 36K). After a week, they rebalanced all 4 tires and replaced the rear ones. The sound did not go away. Could this be linked in some way to suspension wear and tear items. I do mostly highway driving. Any suggestions will be greatly appreciated.

Andre

nvbanker

If you've eliminated the tire as the problem, it has to next be in the moving parts remaining, ie; brakes, wheel bearings, CVJs, etc.... A qualified mechanic should check it out.

jerry5505

I am checking out tires for my car. At the Present time I have Dunlop 5000's which have approx 40,000 miles on . Is there anyone out there who have had experiance with other tires and mileage they got out of them?? Please let me know.

mrcleaner

I have a 2004 LS 430 and I replaced my Dunlop 5000's with a new tire by michelin, "Primacy MXV4". They are very quiet and have soft ride, I have put 5000 miles on them and am very satisfied, would highly recommend them for the LS. They also carry a 60,000 Mile treadlife warranty. Check the Michelin web site for further info, not much feedback on line about this tire because they just came out for sale 6/1/07. I wrote a post about this tire msg #8135 if you want to reference back. Hope this info helps.

lucian95

You've done well with Dunlops. I believe mine were changed after 35K. Next, I bought TOYO Proxes TPT and I'm into 50K with them. They will go for another 20K. However, they are not as confidence inspiring as Dunlops were (a lot more spinning of rear wheels, especially on wet), but otherwise they are quite reasonable tires. It all depends on your driving style and with good tires, it is always the same story-more performance oriented tires will provide less tread life. If you desire more performance, I'd suggest you stay with Dunlops, because they are excellent tires (ultra high performance all season)or alternatively, try high performance all season, like Bridgestone Potenza G009. They got good reviews on tirerack. I suggest you check out www.tirerack.com and purchase tires from them. They will provide you with the recommended installers in your area.

Regards,
Andrej

famwald

Next, I bought TOYO Proxes TPT and I'm into 50K with them. They will go for another 20K. However, they are not as confidence inspiring as Dunlops were (a lot more spinning of rear wheels, especially on wet)

I thought the factory-installed Dunlops had an awful lot of rear wheel spinning on our 2004 LS430, even on dry pavement.

After 40k miles and now going into winter, we recently replaced the factory-installed Dunlops with the Michelin MXV4 Primacy. I can tell that they grip the road much better.

jerry5505

I purchased the Michelin Primacy MXV4 with a Warranty of 60,000 Miles about a year ago and I like them very much. Thanks for getting back to me.

mrsincere7

Can someone advise me? I have a 04' LS 430 Ultra. Lately I noticed a rattling noise coming from the right rear wheel. When I drive down the street it feels like the car suspension is teetering from front to back. I hit bumps and it feels like the car sways before it corrects itself. I even tried to push down each fender. That r/r fender definitely has more bounce than the other sides.

Here's my question. Since I have the electronic air suspension, is there a shock absorber that can be easily replaced, or is it more involved, like replacing a special strut or special shock absorber for air suspensions???

nvbanker

The air suspension is a special strut, it's expensive, but is possible to replace yourself if you have some decent tools and a spring spreader. Sounds like you have one that is bad, but it should be allowing part of the car to sag I should think if it is. They are about $1,000 to buy.

mrsincere7

Thanks for the reply NV. You are quite correct, that strut was bad. In fact it was bad from the day I purchased the car a year ago, but didnt realize it was. When I started hearing a clunking noise coming from that strut that caused me to investigate further. Yes indeed that strut was around $1,000. Fortunately, I have a good and honest mechanic who ordered it ( about $80 to ship it overnight ) and installed it, all for $1,250. Not bad considering how much a Lexus dealer would charge for the same job.

Oh man what a huge difference in the ride!!!! :shades: Now I can fully appreciate what the air suspension struts do to make the ride comfortable and/or sporty. Major improvement from the 96' LS 400 I had before this LS 430. Thanks again for your input.

wwest

Your air shocks have an electrical "component" that dynamically adjusts the shock bounce and rebound effects. My guess would be that the electric connection was loose, intermittent, or the electric feature/control had failed.

A defective, actually defective, air shock would have undoubtedly resulted in that corner of the car sagging overnight.

Interested in selling the "take-off"...??

mrsincere7

If you are refering to the bad strut? I left it with my mechanic, and have no idea what he did with it. He showed me where it was leaking. As for the sagging........when I had the old strut on the car, I used to look at the car from the back ( walking up to the garage ) , and it did appear that the car was leaning more to one side. Initially I thought the floor was just uneven or that when I started to drive the car would balance out eventually. Now of course I am very happy with my "new ride".

wwest

As it happens at this very moment I'm troubleshooting the air suspension on our '91 LS400. Th driver's side rear sags after setting overnight. Start it up and within a few minutes everything seems normal.

So far I have swapped the L/R pressure lines going from the manifold in the trunk to check for leaks at the manifold connection and the leak remains on the driver side rear.

Now off to Lowes to buy new o-rings to install just to be sure and probably some black rubber cement in case I have a leak in the shock itself. But next up is a check of the air pressure connection to the shock itself.

Anyone know what the most common point of failure is...??

Probably the shock itself but checking the easier stuff first.

wwest

Tiny, tiny, slits in the boot bottom just at the fold for normal level. Covered/filled with black rubber cement and tomorrow the test.

wwest

Found a shop that will repair/rebuild our rear air shock for $250 plus shipping.

http://www.suncoreindustries.com/lexus-pages/ls400/lexus-ls400-rear-suspension-s- trut-shock-driver.htm

keywester

I have the airstruts on an LS 430 and one of them needs to be replaced. My mechanic (who I trust totally) originally suggested replacing both of them. That was before we realized how expensive they are. Do we need to to both? Also, where did you order yours from? We are having a hard time finding them locally.

vcheng

Normally your mechanic is correct that struts should be replaced in pairs. However, air struts are different and can be replaced individually. You can try here:

http://www.sewellpartsonline.com/

but there are several other online vendors as well. Please compare several sources before you order using Google for the best deal.

wwest

You don't say if it's the front or rear. The front air struts aer more complex and therefore more expensive to replace. At these prices I woul go the extra mile to get assurance that the problem isn't elsewhere.

On our '91 I was able to swap the pressure lines left to right at the rear pressure metering manifold in order to determine the true failure point. The driver side rear had a series of small slits at the most common ride heigth air bladder fold point.

helchacha

Hi All,

I have an issue with my 05 ls 430 Ultra. Car only has 36K so its in pretty good shape. Someone rear ended the car about a month ago. The damage was actually on the driver's side rear of the car almost all the way up to the gas tank lid. I had the car repaired from a lexus certified collision center. But now the whole car is leaning/sagging to the right. I have noticed this inside the garage which is a flat surface. I stuck my hand in between the wheels and the fender/quarter panel to measure the space in between each wheel and fender and its definitely different on each side. Also when I'm going over bumps I hear a thump noise coming from passenger side rear of the car. I have taken the car back couple of times and it seems that they either can't fix it or aren't fixing it. If someone could please help or point what could be causing the car to sag to one side. I would really appreciate it.

rkls430

I own an LS430 2004, I hope somebody could offer some advice to my question: when I go over bumps or over road irregularities, a "metal to metal" contact noise is emitted from the front tires. It seems that the suspension is loose or not firm enough to absorb the shock. The lexus dealer could not find anything wrong with the suspension. Is this normal? Any advice on this matter?

Thank you very much

wwest

I just learned something new...

The strut-mount, the top mounting plate for the shocks is an active part of the LS' suspension. I always thought it was simply a "solid" mounting plate, shock "tower". After replacing the shocks and the lower ball joints my '92 with 155,000 miles still has the "clunk" at the front when driving over road irregularities.

Order the strut-mounts, "suspension support" this AM. $109 each, discounted, at Lexus, $50 aftermarket.

Discovered the story of the "strut-mount" via the internet forums.

Apparently a fairly common, early, failure point of Toyota and Lexus suspension systems.

rkls430

Thank you, I will take my car to the dealer and mention the "strut-mount" as a potential cause of the "clunk" noise every time the car passes through irregularities on the road especially at low speed

wwest

Live and learn...I guess...

The thunk was not the strut mounting plate at all. It was the rubber cushion/insulator (with the protective bellows/boot attached) between the spring and the strut mounting plate. The insulator/cushion had worn down and been compressed so much that when going over the slightest bump the top of the spring would hit/contact the bolt head holding the mounting plate in place.

Slid 14" of 5/8" ID automotive water hose over the top end of each of the front springs...

No more "thunk".

wwest

WOW..!!

Truly amazing...

How quietly riding a '92 LS400 with >150,000 miles can be with the top of the front coil springs NOT striking the bottom of the strut mounting plate when going over minor roadbed pertubations, bumps.

wwest

Keep seeing posts about failing air suspension shocks.

Has anyone tried sealing these with the "green gunk" found at Home Depot and the like that can be used to seal lawn/garden tractor tires..?

rennybosch

No experience with green gunk, but another post about failing air suspension shocks:

Our '04 LS430 with 80,000 miles recently started driving like a truck, so we took it in to the dealer and they confirmed the air suspension struts were bad. Fortunately we have an extended warranty, which covered all but the deductible. They replaced all 4 struts. The insurance company paid $5,700, I paid $200. Now she rides like a magic carpet again.