Tec80

My car has been giving me the power steering failure warning intermittently for about 2 years. Usually I turn the car off and restart and it clears up. I discovered this is due to a connector issue on the right side of the engine compartment. I found this video At 2:48 describing the issue, and I unplugged the connector and sprayed contact cleaner in it - presto, no more steering warning!

However, maybe due to steering the car without power steering, the rack now makes a noise when turning the steering wheel back & forth. Sounds like a bad bearing in a roller skate wheel. No play in the steering, and the power steering still functions perfectly. SO I searched for more information on this, and found this video showing the rack motor disassembled:
At about the 30 second mark, you can see the motor armature that spins at a high speed when the steering shaft is turned, and my rack's bearing noise corresponds to this armature speed. So likely I need a new rack.

I have the USF40-AEZQH SZ sport model, which uses a unique rack (44200-50290). The Sport supposedly has the different rack to give sharper turn-in, but I've never noticed any difference vs. our other LS460. Also, the racks are different between air suspension cars, vs coil spring cars (not sure what air suspension has to do with the rack).

I'm planning on sourcing a used rack from ebay since the price is around $400 and it's relatively easy to replace. Does anyone know why the racks are different on air suspension LS460s?

Thanks!

V8ski

Do you hear this bad bearing sound from the steering rack all the time? or just when the motor is off?
While diagnosing a front end clunk related to steering I tested the rack and noticed there is a bearing like noise when it moves without assist / engine power. I didn't really hear the noise with the engine running. Since the steering functions perfectly, I'm thinking this noise is totally normal and not worth replacing the rack until it fully declares itself.

Tec80

It's only when electric power is on. I press the start button twice without pushing the brake pedal and it powers up the rack, then the noise is easy to hear. It's definitely different from how it used to be.

V8ski

One would hope the rack could be rebuilt or the culprit bearing could be replaced, though my google search turned up nothing. If you do swap out the rack it would be great to get more info on how the original failed.

caha14

Excellent research and findings! Air suspension cars have AVS and VGRS, the latter being the reason.

Tec80

Good point! I need to disconnect the steering shaft from the rack and see if the noise is in the VGRS unit or the rack itself. I've been bitten before by the Parts Cannon approach, when just a bit of labor would have shown me the exact offending part. I drove it today and the steering is a bit "sticky" off center, so it's very likely a failed bearing somewhere.

Tec80

Wow, I drove it on the freeway at high speed and it's "sticky" over center, making the car feel very unstable and darty. Definitely the rack itself, as VGRS would disable itself and lock the input to the output and set a code if it malfunctioned.

Now to find a replacement rack for less than $2100, ugh.

Tec80

I contacted Lexus customer service, and got the standard "it's out of warranty" response. So when they sent a follow-up survey, I let them have it. I mentioned that this is a safety issue, that my car has never seen salt or winter weather, and that this is the first time I've ever had a car fail a steering rack. I thought they might be interested in a fault like this, because it could result in a crash and even if it's an isolated failure, it should not have happened.

I'm also a bit annoyed that the list price for the rack is $2800 and they don't sell any component parts (like the bearing that failed in my rack). I found one at a junkyard in TX, but they don't ship. It's a specific part only used on the 2010 until 8/2011, so it's a relative unicorn.

Since I have nothing to lose, I'll take the rack apart to see if I can replace the bearing. Evidently the Honda S2000 used a nearly-identical EPAS design, and there are people who rebuild those. Related link: https://www.s2ki.com/forums/s2000-mo...pinion-885422/

I'll share what I find inside my rack, likely it's one of the armature bearings.

Sherl

Where in Texas? If it's Austin, prolly I can help

Tec80

It's in Kennedale, just SW of Fort Worth.

Tec80

I found out that the rack part number has been superseded, from 44200-50290 to 44200-50430. A bit of web searching reveals the armature bearing part number, which is BDZ45-3.

I started removing the rack, and got everything disconnected except the tie rods. For those, I had to buy 29mm and 34mm open-end spanner wrenches to unscrew the inner tie rod ends from the rack shaft. The reason for doing this was that I can preserve the alignment by leaving the entire R&L tie rods untouched (the inner tie rod ends swivel). I'll then take the rack apart to see what bearing failed. If it is indeed the BDZ45-3, and I can remove it carefully without damaging anything, I'll buy a new bearing and rebuild the rack.

Some labor and a $100 bearing, vs. $3400 (list, ouch) for a complete new rack. Yeah, I'll give it a shot.BDZ45-3DZ45-3

swfla

iTrader: (1)

Keep us posted and hope you succeed.

Anfanger

44200-50290 is likely a sub-assembly part number. However, 44200-50430 is an actual part number and it only superseeds 4420050270 and 4420050271. Can you provide a reference to support your findings regarding steering rack part numbers?

Tec80

Second line:
http://jp-carparts.com/lexus/partlis...ype=3&fig=4505

Anfanger

Thanks, where does it provide information about superseeding?