I have decided I’m going to replace the struts in my car with Lexus OEM struts but I think I can save some money and replace the mounts with aftermarket. I see that KYB makes front strut mounts, but I can’t seem to find the rear ones. Does anyone have any good suggestions?

 

@e-man You don't see the rear "mounts" because they generally do not need replacing unless they have severe corrosion that compromises their structural integrity. They are basically a hollow metal body/sleeve that can be reused. The rear "mount" kits you usually see are the rear bushings for the mount. I would recommend to replace those because they do wear out over time and they're cheap to purchase.
I replaced all four shocks on my '11 GS350 AWD last fall. I went with aftermarket KYB replacement for the shocks, front mounts and rear mount bushings. The car is smooth and comfortable without any issues. Everyone has their own opinion, but I feel that my choice was the best overall for price, comfort and quality. The rear mount kit (bushings) from KYB is: SM5597 and should be the same even though they say it's not for adaptive suspensions.

 

KYB is very explicit on their website that the shocks that they sell are identical to the OE ones the provide to Toyota and other manufacturers. They expressly call it “OEA” - original equipment aftermarket - meaning same parts, just direct. The shocks you bought are in fact the same as came on the car or you pay more for once Lexus puts their part number sticker over the top of the KYB one (yes, that’s how they sometimes come from Lexus).

When the last shock change on my 3GS was done (2024), the Lexus shocks that came off just had Lexus stickers over the same KYB numbers as went back on from KYB. No difference at all.

 

Thank you!!! That’s exactly what I needed to know.

On the question of KYB versus “Lexus,” you guys are absolutely KILLING me. I researched the heck out of this question, called and emailed KYB, reviewed a ton of threads, and I believe they are similar but not exactly the same. According to the person I talked to and emailed with at KYB, the KYB aftermarket version is tuned approximately 10% stiffer than the Lexus version. They told me that the reason they do this is because they assume that people who are replacing struts on their high mileage Lexus are not going to replace other work components and they tune the shocks 10% stiffer to account for this.

The difference in price is significant. The KYB shocks are about $100 each whereas the Lexus ones are about $250 for each front corner $290 for each rear. And the KYB front mounts are about $75 each whereas the Lexus front mounts are about $150 each.

My biggest fear is that I will go with the KYB shocks to save money and they will make the car ride too stiff for my liking. I’ve had the car for over 13 years at this point, and I plan on keeping it for years to come. In fact, I just recently replaced my second timing belt and water pump.

@Oro How many miles were on your 350 when you replaced the shocks?

@TopNotchIN Same question to you.

Do either of you notice the ride more stiff now than when you had the stock OEM shocks (when they were still doing their job)?

 

@TopNotchIN I don't see KYB rear mount kit as an option for my car. I looked up the part number SM5597 and it looks like it should work for a RWD car, but I'm not sure whether the mounting hardware would be any different for a car with adaptive suspension with the actuator sitting on top of the strut. You would think that shouldn't make a difference.

 

I don’t quite follow how replacing the OE shock w/the OE shock will make it stiffer. KYB is the OE shock and the shock they sell is the OE shock. No risk.

I re-did the car about 180k; it was badly in need and needed it sooner. But I was not driving it and did not know; another family member had it then.

 

Other than that KYB specifically told me that they tune the shock 10% stiffer than the Lexus ones to account for the fact that most owners of Lexus cars with high miles won’t replace other worn suspension parts. I just don’t know how to quantify 10% in terms of real world feel.

 

KYB publicly says that’s not the case. Who did you speak with, I’ll call them and discuss it?

 

I don’t remember the person’s name. It was a while ago. I just called the customer service line.

 

Ah, the anonymous CS person who contradicts the engineers, marketing department, and customers’ experiences. Got it.

 

oh, he had a name. I just don’t remember it. I’m gonna give them a call again tomorrow and see if they can confirm or deny this once and for all.

 

So I just went back and checked my old posts and it looks like I must’ve emailed KYB CS last year, not called them. Here is the response I got from them.

“The aftermarket shocks usually have around 10% higher damping than OEM.”

I just emailed CS again today. Unfortunately there’s no number to call. Let’s see if I get the same response. I’ll post back up hopefully tomorrow.

 

So I emailed KYB yesterday and asked the following: "I have a 2006 Lexus GS430 with the original Lexus shocks made by KYB. Are the KYB aftermarket replacement shocks identical to the KYB/Lexus shocks that came on my car from the factory? Are the specifications the same? Are they tuned the same?"

Here is their response: "Yes, anything that say OE replacement from us has to be very similar to OEM new. So with 200k miles they will feel different once installed because they will be the equivalent to what it would have felt new."

So I guess "has to be very similar" is the best we're going to get from KYB CS. I followed up to ask them about what I was told last year (10% firmer). My guess is that they will say that's about right.

 

And here is their response to my question about the replacement KYBs being 10% stiffer:

"That is also correct, 10% increase is common KYB damping increase compared to OEM. Most people won't notice it due to the difference is taking into consideration worn out suspension that most people don't replace so the shock/strut damping makes up for it, improving handling."

@Oro Unfortunately, these emails are signed "Technical Support KYB Americas Corporation techsupport@kyb.com, without anyone's actual name.

I think the bottom line is that the OE KYB replacement shocks are similar, but not the same, and are slightly stiffer than OEM to account for other worn suspension parts. Most people wouldn't notice a difference.