I brought my 2010 RX 350 AWD to the dealer for it’s 60K mile oil change, air filter and brake fluid replacement, and the list of various vehicle 60K inspections.

The service rep called me over and said that the he recommended the following work:
- replace the main drive belt which was fraying ($215 parts & labor)
- drain & refill front / rear differentials which he said had darkened oil ($204 parts & labor)
- replace the vent valve sub-assembly which he said was bad ($87 parts & labor)
- replace the motor inside the steering column which was intermittently squealing ($3,000 parts & labor, thankfully covered by extended warranty...I am very surprised...had a Ford for 14 years and a Mercury for 10 years and never had anything like this. SO MUCH FOR LEXUS RELIABILITY.

What upsets me more is being advised to drain & fill the differentials at 60K miles. I had an AWD Mountaineer for 10 years & 130K miles and never touched the differentials.

The 60K maintenance list says to “inspect” the differential oil, but it seems the dealerships use that as a way to squeeze more money from the service visit, advising that the “fluid doesn’t look good.” WHY IN THE WORLD SHOULD I NEED NEW DIFFERENTIAL OIL ON A LEXUS THAT COST OVER $45K, WITH ONLY 60K MILES ON IT...WHEN MY OLDER SUVS NEVER NEEDED SUCH WORK?

I went online and found several other owners complaining of EXACTLY the same thing at their 60K mile service visits. Has Lexus prepped their service reps to scam up differential fuid service when it’s not needed? Sure seems that way.

 

I'd be so happy that my dealer's diligence picked up the issues - and patting myself on the back for taking it to the Lexus dealer (who is authorized to exchange the errant motor under warranty) - that I couldn't write the check for the fluid changes (which will, likely, extend the life of the differentials for the subsequent owner) fast enough.

If you truly distrust the integrity of your dealer, there are myriad other service garages - none of whom would have fixed your squeaky steering for free.

As a check of the dealer's expertise, have them draw samples of your gear oil, have them analyzed, and affirm/refute your suspicion(s) with empirical data.

 

...dealers are for WARRANTY work only. So, let them fix the motor and take your Lexus to a reputable independent for the rest. Frankly, you should have had the routine maintenance done by an independent even while you were under OEM warranty. It saves money, builds a relationship, and lets you suss out the independent as a reliable partner.

 

I would like to know what is the vent valve sub-assembly that costs $87. Is that a fancy way of saying replace the PCV valve? Try to find out what it is venting and the part number.

I would also check with a reliable independent on the belt replacement cost. This engine is common to many Toyota-Lexus products, so they will have experience with it.

I think they are way overcharging to replace the differential fluids. I can do both of mine in less than an hour and I only have 2 floor jacks and 4 jack stands. And I use synthetic fluid. It is a good idea to replace that fluid at this time. I did mine at under 30,000 miles, but I get obsessive about preventive maintenance and fluid changes.