Lexus GX460 2020 – Comfort-Oriented Suspension Advice

[Kyrylo25]

What tire pressure are you running?

Whenever my truck rides like s*** its because some tech put 40 psi at each corner. I run my 34s at 30 psi and can still get decent mileage.

I have 95 lbs a corner with e load range and its still smooth with bumps. Just some NVH from the mud tires.

I commute over some crappy roads, so tire pressure is critical.

30-34psi

 

[Kyrylo25]

Before you buy new shocks, have you checked your tire pressure?

30-34psi

 

[Kyrylo25]

That's a speed rating, not a load rating. What is the tire size? (Not the 32.5" mentioned, the actual size stamped on the sidewall)

Falken Wildpeak A/T4W 285/70R17 (Trd rims)
Pressure tested from 28 to 35 psi

 

[Roody]

Falken Wildpeak A/T4W 285/70R17 (Trd rims)
Pressure tested from 28 to 35 psi

So you said they're 115T speed rating, which doesn't exist for that size and tire

285/70R17 - 116T - SL
LT285/70R17 - 16/113R - C
LT285/70R17 - 126/123S - E

So if you have the SL-rated version, your issue is the weight. If you have the C or E, your issue is the weight and the stiffness of the sidewall. Not the suspension.

 

[Hiluxforever]

So you said they're 115T speed rating, which doesn't exist for that size and tire

285/70R17 - 116T - SL
LT285/70R17 - 16/113R - C
LT285/70R17 - 126/123S - E

So if you have the SL-rated version, your issue is the weight. If you have the C or E, your issue is the weight and the stiffness of the sidewall. Not the suspension.

Could also be tires with road force issues.

 

[Kyrylo25]

So you said they're 115T speed rating, which doesn't exist for that size and tire

285/70R17 - 116T - SL
LT285/70R17 - 16/113R - C
LT285/70R17 - 126/123S - E

So if you have the SL-rated version, your issue is the weight. If you have the C or E, your issue is the weight and the stiffness of the sidewall. Not the suspension.

I don't understand why you listed this if I wrote in the title that due to the extra weight of the wheels my original struts are not able to work properly...if you have technical knowledge of strut structure I would appreciate advice on strut selection with my original query in the title.

 

[Banandalorian]

If you want maximized on-road comfort with no lift on heavy 285/70/17s that also works for "overlanding" then pony up for a high end adjustable and/or custom valved setup and upgrade your bumpstops.

The factory setup on the 460 is slightly underdamped because its more comfortable for most driving but in general its pretty good. It will crash through the bump travel on big, high speed bumps but to actually get better damping than Lexus provided from the factory requires money.

 

[Roody]

I don't understand why you listed this if I wrote in the title that due to the extra weight of the wheels my original struts are not able to work properly...if you have technical knowledge of strut structure I would appreciate advice on strut selection with my original query in the title.

You have yet to tell us your use case, which directly impacts what we recommend as far as suspension goes and at a higher level what could be causing your issue of a "harsher" and "jittery" ride.

Logic tells me:
Ride quality was fine --> You added tires that are 20 lb heavier --> Ride quality suddenly "harsh" and "jittery" --> Problem is the tires

Changing the suspension when the symptoms you're experiencing are due to heavier tires is a band-aid if your use case doesn't necessitate an altered suspension setup, which from you telling us you want to retain stock ride height leads me to believe the upgraded tires aren't for significant off-road use, or at least not use that necessitates increased ride height. Instead of chasing possibly expensive suspension replacement, why not try a lighter tire that doesn't add 20 lbs per corner?

If you don't need better suspension for any reason use case situation like off-roading, you're spending money you don't need to spend by replacing the suspension and not just going to a lighter tire. It's your money and I won't tell you how to spend it, but that's just how I (and it seems everyone else responding to this thread) sees the situation.

 

[Kyrylo25]

You have yet to tell us your use case, which directly impacts what we recommend as far as suspension goes and at a higher level what could be causing your issue of a "harsher" and "jittery" ride.

Logic tells me:
Ride quality was fine --> You added tires that are 20 lb heavier --> Ride quality suddenly "harsh" and "jittery" --> Problem is the tires

Changing the suspension when the symptoms you're experiencing are due to heavier tires is a band-aid if your use case doesn't necessitate an altered suspension setup, which from you telling us you want to retain stock ride height leads me to believe the upgraded tires aren't for significant off-road use, or at least not use that necessitates increased ride height. Instead of chasing possibly expensive suspension replacement, why not try a lighter tire that doesn't add 20 lbs per corner?

If you don't need better suspension for any reason use case situation like off-roading, you're spending money you don't need to spend by replacing the suspension and not just going to a lighter tire. It's your money and I won't tell you how to spend it, but that's just how I (and it seems everyone else responding to this thread) sees the situation.

What suspension would you recommend for softness and the ability to handle the addition of 20lbs per side

 

[JZGarage]

lol Mudders really working for their keep on this thread. Painful.

OP - a little friendlliness and gratitude to those trying to help you out goes a long way.

As mentioned, if the rubber you installed is an E load rating, that's most probably the culprit.

 

[Kyrylo25]

lol Mudders really working for their keep on this thread. Painful.

OP - a little friendlliness and gratitude to those trying to help you out goes a long way.

As mentioned, if the rubber you installed is an E load rating, that's most probably the culprit.

I understand that there is a reason for the problem, but what is the solution then ?roll back to the original wheels ?why do the offroad project at all...

The question is specifically "which suspension will work best with the extra weight".

 

[ericm979]

No suspension will be able to mask the added unsprung weight, or the stiffer tire casings that these heavy tires surely have. The stock shocks are already the softest riding (least damping) suspension that's available. More damping will make the suspension stiffer, which is usually considered less comfortable.

If you think the ride is bad after the tire change, then you're going to have to decide if big tires, and these tires in particular, are more important to you than the ride.

 

[Kyrylo25]

No suspension will be able to mask the added unsprung weight, or the stiffer tire casings that these heavy tires surely have. The stock shocks are already the softest riding (least damping) suspension that's available. More damping will make the suspension stiffer, which is usually considered less comfortable.

If you think the ride is bad after the tire change, then you're going to have to decide if big tires, and these tires in particular, are more important to you than the ride.

I believe my shock absorber is not working properly it just doesn't have time to work in time, the wheel literally falls through the hole and doesn't have time to go any further up.

 

[Roody]

I'm going to politely excuse myself from this thread.

 

[thescreensavers]

Eibach is known to be a good compromise shock that is still comfy. You are better off buying a setup and trying it out. Everyone opinions will differ from yours.

Unsprung mass and E load is working against you but if you like the look just get used to this new normal.

 

[Kyrylo25]

Unfortunately, I couldn’t find a full KYB lift kit in stock. First, PartsGreek sent me the rear shocks without the springs and told me I had to return the shocks before they would try to locate the springs. After that, I tried to find the front KYB SR kit in stock, but after calling 5–6 stores, I realized it would most likely be a special order anyway and not worth wasting time. I also didn’t understand why the rear shocks were delivered uncompressed or not even partially compressed. In the end, I decided to go with the Fox 2.0. You can see a detailed comparison of the rear shocks in the photos.

 

[Seavs]

Unfortunately, I couldn’t find a full KYB lift kit in stock. First, PartsGreek sent me the rear shocks without the springs and told me I had to return the shocks before they would try to locate the springs. After that, I tried to find the front KYB SR kit in stock, but after calling 5–6 stores, I realized it would most likely be a special order anyway and not worth wasting time. I also didn’t understand why the rear shocks were delivered uncompressed or not even partially compressed. In the end, I decided to go with the Fox 2.0. You can see a detailed comparison of the rear shocks in the photos.

View attachment 3956477View attachment 3956478

Curious as to how you landed on the Fox? Seems like a higher performance (stiffer) shock that you were originally looking for.

 

[Kyrylo25]

Curious as to how you landed on the Fox? Seems like a higher performance (stiffer) shock that you were originally looking for.

I have spent many hours on YouTube watching comparison videos of different stores and workshops and 10/10 said it was the softest upgrade.Unfortunately only 2 posts on reddit and 3-4 videos and asian countries said KYB made the car softer.Also I still want to try (at least for experiment) the shock absorber kit KYB but not in stock .
Maybe next week I will install Fox 2.0 and give feedback.