Recently took my wife's 2010 RX350 to a local Toyota dealer (nearest Lexus dealer is over 30 miles away) for routine 50K mile service.
Yes, it really does only have 50,000 miles on it.

The dealership claims that it needs a new Steering Rack ($1,578), as well as a 4 wheel alignment ($130), and front & rear differential fluid replacement among other item that came to a total of $2, 638. I did not authorize ANY of the work - just paid for the 50K service and left.

They claimed that there was some 'leakage' in the steering system, although I have never seen a drop of fluid on our garage floor under the vehicle.
Any suggestions on inspecting the steering rack/system myself to verify if any service is required?

 

Rack leakage is not evident (other than needing toping up at the reservoir) as the leaked fluid stays inside the boot. The boot is like bellows which expands and contract as the steering is turned and tie-rod shafts extend or get pulled in. There is a clamp on the boot end and if you remove it. the fluid would run out. Just make sure you put back the clamp with the steering centered [you want the natural state of the bellows with the steering straight ahead. This preserves the life of the bellows and if you rip them you have to go through lot of trouble.

Salim

 

What fluid reservoir are you referring to? I thought our cars had EPS. No reservoir.

 

I agree, what fluid is there with electronic power steering? I could understand some grease may need replacement if a bellows tore. He needs a second opinion from some independent shop with less interest in meeting sales quotas. I think the dealer is pulling a fast one and does not even know it has EPS.

 

I have hesitated to answer (hoping one one who has actually worked with the rack would).
If you guys give me the latitude .. the electric motor does not directly drive the rack. The electric motor drives the pump and the hydraulic pressure moves the rack. The reservoir is now built in the rack and has a fill bolt.
This is educated explanation based on hydraulic fluid leak.

Salim

 

That is not the way it was explained to me. My understanding is the system uses servos to assist the steering. I do not know this for sure. It is just what I was told.

 

Not much help, but it says there is no fluid.

 

Found one for Lexus where he takes it apart.
Have not watched it yet, I am at work after all.

 

Excellent videos. Just as I suspected. No fluids and all done with servos. There is NO reservoir.

 

This is steering column and not the rack. The rack sits between the column and the wheels .. that is where the hydraulic function is. Steering column has the electric motors for tilt and in-out motion.

You can see hydraulic piping and the long bellows (on tie-rods) is the place where the leaked fluid accumulates. The seals at the rod ends end up leaking. Looks like a closed loop system.

https://www.detroitaxle.com/shop/steering/complete-power-steering-rack-and-pinion-assembly-toyota-highlander-lexus-rx330-rx350/?fit=8&gclid=Cj0KCQiAw9nUBRCTARIsAG11eid9je9gDluDF4hXCiJ_t2UIzyO7WuqMjuteaKJb2VlhxwMW0FlIqSIaAgdVEALw_wcB#

Salim

 

The EPS on the RX350/RX450h does not use any hydraulic fluid at all. Here is a picture of the steering rack - it has no hydraulic piping at all.





There is absolutely no hydraulic fluid in the rack system. The assistance comes from servos high up, away from the steering rack. The rack itself is incredibly simple, but it is filled with an appreciable amount of grease.

Back to the original post, if there is a "leakage" its coming from elsewhere, as there is no hydraulic fluid. The "leak" must be coming from elsewhere. Perhaps a misdiagnosis, and it's actually from the dreaded the engine timing chain cover. Or maybe one of the rubber boots at the end of the rack is compromised, and is leaking grease.

 

I have owned my 2010 RX350 (non F sport) for about a year now. Car is in phenomenal shape. There is one thing about the car I cannot stand. The light electronic steering feel is luxurious and beneficial everywhere but the highway. It takes so many adjustments to keep the car tracking straight at speed. I had a tech at the dealer look over the car and drive it to see if by chance there was something wrong. They said it’s in perfect working order. I have seen a couple threads on here that mention the light steering, but none addressing if there is a way for it to be tightened. Any solutions out there? I am on relatively new michein premier ltx. Alignment was also verified. Any help here is appreciated. I have pondered seeing if any F Sport parts can be swapped in, but unsure if that will solve the problem.

 

How many miles are on it? Do you have 18 inch or 19 inch wheels? What is your tire pressure? Are these tires and symptoms new? Meaning did it feel this way before you got the new Michelins? You could have a bad tire which is causing belt steer and creating your tracking problems. I would have another shop check your tires etc. as it could be technically in alignment and still need further adjustment to drive correctly. Are you in the DC suburbs? If so go to Satellite Motors.
Did you get them from the dealer?

The only difference with the F Sport is stiffer struts in front and stiffer shocks in back and you can change those. Plus some lateral dampers that don't do much and you cannot add anyway. You could swap struts and shocks to the stiffer F sport stuff, or the better B6 Sport Bilsteins that fit the 2014-2018 Highlander (I have these) but you may not like the new stiffer ride and it may not make it steer any better.
However new regular struts and shocks may help, but also may not make any difference, but the B4 Bilsteins are for the regular suspension and will maintain the stock ride. You would need an independent shop to do this work as I doubt a dealer will install these on an RX..
I don't think you can adjust the steering itself to tighten up the electronic assist.

 

115k miles on the car. I bought with 95k miles about a year and a half ago. Vehicle was a single owner and was maintained at Lexus regularly. All four tires have about 8/32 on them and are matching. I run the tire pressure listed on the door jam, I think it’s 35. I have the 18” wheels. Funny you mention DC, i bought the car from Rockville Lexus. Do you think lower profile tires w the 19” wheels makes a difference? Or even running higher tire pressure? I have done a lot of suspension work on 4Runners and I agree not sure how much stiffening the dampness of the ride would help with the steering feel at high speed straight line. I am up for trying anything to be honest, this light steering at speed is pretty awful.

 

Do you observe any change if you swap the wheels [front to back]

I would suggest take it to speed shop.
Make sure they check suspension for any wear.

Ask them to set the toe-in deliberately to extreme allowable value [normally the shops try to get close to the middle].

Salim

PS: My suggestion will not help in the 'feel' but it should help in directional stability/wandering.