If a tapered rolling element bearing fails, it is usually caused by
1. Foreign object damage
2. Fatigue stress (cyclic loads)
3. High axial loads resulting in roller end damage and subsequent twist loads on the cage
4. Geometric stress concentrations due to position or installation
5. Insufficient lubrication or incorrect lubricant

The comments about bearing quality OEM vs chinese are suggesting that the cheap bearing cannot bear the cyclic stress loads for the expected bearing life. This can be due to poor surface finish, heat treat, hardness, material defects, metallurgy etc

If bearing installation is improper, then races can be harmed as the rollers impact this surface creating stress concentrations or crack initiation sites.

The repeated failures at one location point to bearing quality and installation.

If you would post a bearing failure image the causes might be more guessable.

Just looked up the actual part for this year and model.
They are sold as a hub and bearing assembly and simply bolt in place. So the issue is more likely the quality of this part as any moron should be able to do the job.
The NAPA part is $90 and the OE online is in the high $300 range which makes me suspect Chicom or other third world bearings.
Make sure they are using either OE or other high quality brands like Timkin.

there are discounting lexus dealers with online parts sales.

you could see if there is a toyota matching part.

Then again if you paid $100 for the aftermarket and it's failing adding $200 for a OEM puts you at $300, which is MSRP for new.

You may want to get another shop to look at it and see what they think the issue is, other than that, have them put another one on, it's under warranty, see if it fails, if so, you have other issues because 3 bad out of 4 bearings isn't normal, even with Chinesium...

Since it's the same side doing the same thing, and the original problem was a bad bearing, suspect that it's something else in the rear suspension or drive line, perhaps axle is bent or out of spec from hitting a pot hole, wheel, any number of things.


Several listed on ebay, original Toyota/Lexus part in the low $200 range, you want to google the PN it's 42410-50010.


Ebay

My dad had an LS 430 from 1991, that sumbitch went 300K damn near bulletproof.

He had a rear spring issue as well. Turns out that he was going through bushings/bearings a few times, there was apparantly an installation problem. Once the dealer figured that out, they never broke again.

I just had my rear bushings go out at 2 months after a rear shock replacement job on my escalade. They got OEM bushings and swapped them out, and it has been perfect ever since.

quote:

Originally posted by Timdogg6:
My dad had an LS 430 from 1991, that sumbitch went 300K damn near bulletproof.

1991 would have been the predecessor the LS400. Read an article not too long ago that I wish I could find. But Toyota spent 1 BILLION dollars in R&D for the LS400! That’s nuts! 1 Billion dollars in the late 80s.

The LS400 and LS430 are arguably the greatest sedans ever built. Specifically luxury sedans.

^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
You are correct, the bearings come in a hub assembly.
The shop has alignment equipment, I'm guessing that after two times, on there dime, they will look long and hard for the cause.
This is not an easy job.I originally paid almost $2000 to have both replaced.
The car goes back Tuesday for another attempt.

2001 was the first year of production for the LS 430. 2001-2006 was the production run for the LS430.

I just noticed you are in Chicago.
You need to take it here
https://tccnautomotive.com/

If you don’t watch The Car Care Nut on YouTube you need to.
He is probably one of the best Toyota/Lexus Mechanics out there along with Viktor G.
The Car Care Nut is currently doing a series on a 600,000 mile LS430

UPDATE

Took the car in and had it checked, Indeed the left rear axle bearing assembly was bad again.
The shop owner said his research found improper torgue on the axle nut could be the problem. He stated they always use a torgue wrench but the mechanic may have screwed up this important step.

BLACK,I contacted the Car Care Nut about service about a year ago. I was disappointed in his replay when I asked him about approximate charges. He told me I would have to first spend about $150 for an estimate.I was inquiring about having the 80,000 mile service on the timing belt and water pump replacement done (second time). This is a standard operation. I would think he has performed this procedure hundreds of times. He came across to me as arrogant.

New axle bearing assembly installed ( no charge) and its quite now, fingers crossed.
I hope 3 times is the charm.

That’s a bummer to hear about the Car Care Nut.

I've always had issues with NAPA branded parts as godawful trash.