Hello group, I have the following issue: a few days ago, I replaced the steering rack along with the entire front suspension(all parts OEM). The only components I didn't replace are the pump and the lines. After the replacement, I filled the system with Toyota Dexron III (as per specification) and bled the system according to the procedure. I won't go into details about the incredible difference before and after. The problem is that sometimes, when I turn the steering wheel, I hear this strange sound, and it feels like there's some vibration in the steering wheel. If anyone has encountered this issue and has a solution, I would greatly appreciate it if you could share what needs to be done to eliminate it.
Thank you in advance!

 

Honestly I would check the easier things first. My dads ES300 was making a sound like this, and it ended being the rubber boot that seals against the steering shaft where it goes through the firewall. Just a quick shot of silicone lube and its been quiet for years.

Being that they put a new steering rack into it, the would have disturbed that boot a little bit, so I would start there and work my way forward.

 

Thank you very much for sharing the information. Unfortunately, that does not seem to be the case for me. In addition to the noise, the issue can also be felt in the steering wheel. Moreover, if it were caused by the mentioned boot, it would likely be noticeable under all conditions. The problem does not occur when the hydraulic fluid is cold, possibly because the engine revs are higher while the car is warming up. I am considering checking and reinstalling the old banjo bolt (check valve) on the pressure line. If there is no difference, it might simply indicate that the pump is unable to generate the required pressure, and with the new steering rack, this becomes evident—especially under maximum load (when stationary). I also checked the power steering reservoir for bubbles, and in my opinion, there are none—just the fluid moving due to its flow.

 

Hello again,

An update on the topic: the high- and low-pressure lines, as well as the pump, have been replaced with new OEM parts. The system has been bled multiple times, with the wheels lifted off the ground and the steering wheel turned from lock to lock.
The solenoid from the old rack was installed in place of the new one, and although there is a very slight improvement in noise and vibration (old vs. new PPS), the issue remains unresolved.
The steering still feels heavier when stationary, during maneuvering, or at low speeds.
I would appreciate any ideas.

Thanks in advance.

 

I think your RPM's dropped significantly whenever you felt the vibration/heard the noise? Is that happening? It's difficult to see and hear on the video. It sounds like you're wearing a jacket made of aluminum foil LOL. Just kidding. Could it be the serpentine belt or accessory belt? I'm not a motorhead enough to know off the top of my head if the serpentine and PS belt are the same or if they're separate belts? PS...a couple more minutes, and your engine will be fuel starved!

 

Yeah, the RPMs do drop a bit - around 100-150 - whenever that vibration/noise happens. There’s only one accessory (serpentine) belt, and it drives the power steering pump, alternator, and A/C compressor.
The belt itself was replaced about 81,500 km ago (roughly 50,600 miles). The tensioner assembly (TENSIONER ASSY, V-RIBBED BELT) and the idler pulley (PULLEY SUB-ASSY, IDLER, NO.2) were both replaced recently.
Right now, the only thing left to replace is the PULLEY ASSY, IDLER (I’m just waiting for it to arrive any day now), since the bearing is causing some noise and vibration.

P.S. there’s plenty of fuel left in the tank! 😄
Best regards,

 

I found a few more similar cases. In one Reddit thread, a user claimed to be a mechanic at a Lexus dealership. He said they had replaced five steering racks for one customer — the first due to a leak, and the next four because of the same issue — yet they were never able to fix it by using the OEM rack and pinion. Only after installing an aftermarket part was the problem finally resolved. If that’s true, it’s really unfortunate that Toyota allowed such an expensive component to be produced with this flaw and didn’t take steps to correct their mistake!

https://www.reddit.com/r/LS430/comme..._when_turning/

 

I bet You need to inspect the variable vacuum valve on the power steering pump. They start leaking and then power steeling fluid gets sucked into the intake manifold and causes the engine to struggle while it’s burning the fluid. You’ll find the intake manifold will have a bunch of old fluid puddled up in the bottom and causing the ASICs variable intake running length to also struggle. I couldn’t believe how much better my car ran once I got this figured out.

 

Thank you for your reply. Could you please share more details about the exact location of this variable vacuum valve? I think you mean the idle control valve that’s located on the steering line (it’s also new; it came with the lines).
The steering pump is new as well!

Best regards

 

This is turning into a parts cannon - goodluck - be interesting to determine the root cause - thx for sharing

 

I can 100% tell you that guy is full of ****, there is no way 4 oem racks where bad. These cars are not known for having issues with the racks, these are not stellantis products lol. I have 3 430's right now and there is 0 issues with leaks. I have also had these other 430's over the years with 0 issues. The only reason the rack would have issues if the wrong type of fluid was put into the rack, or some type of accident that would cause damage.

I have seen people misdiagnose a leaking front seal as a leaking rack. It sounds like air is being sucked in or there is a vacume of some kind. The 430 should have heavy steering at low speeds. Check your steering shaft heat shield. When I installed my PPE headers the heat shield made a horrible scraping/rubbing scraping sound.
Did you replace your steerimg rack bushings?

Also when you disconnected the u joints did you check them for any play?

 

I can’t speak for the claims made by the guy on Reddit, but I’m 100% sure that the annoying issue started after the rack replacement! The fluid is the correct type (Dexron III). The OEM rack came fully equipped, including the bushings. As for the U-joint, I can’t say for sure if there’s any play, but even if there is, I think it can’t be the cause. The sound and feel are definitely not coming from an external source.

 

Why did you replace the rack in the first place?

Also have you gotten an alignment ?
As I stated above the steering is heavy at low speeds that is completely normal.

 

The old rack started leaking (this was confirmed by two different mechanics) on the right side. Yes, the alignment was done at least twice since the replacement. I remember how the steering felt in the first couple of days — it was just amazing and definitely lighter. I’m wondering if a loose connector or a bad wire to the PPS solenoid could be causing the issue.

 

Hey try replacing this part I am 50% sure it should fix your issue