New Shocks on 2013 LX? (1 Viewer)

[cruisersandlxs]

Hey everybody! So happy to be here as I'm a lifelong Cruiser and LX fan! We purchased our first Cruiser in '89, I was 8 when my dad and I drove from Bartlesville, OK to Lawrence, KS to pick up the rig (1 mile on it) and we had that until my sister totaled it in 2019. Had 357k miles, original engine and tranny. Mom also had a '96 LX450, and a 2003 LX470. So I was thrilled to buy my wife a 2013 LX570 a few years back with 145k miles, one owner, and serviced at the Lexus dealership in Knoxville.

We love the vehicle, it's the first large SUV that my wife actually enjoys driving in. But it seems as if the ride quality has diminished a bit over time in the past few months. We did put BFG KO2s on it in the summer of 21, it appears as if the tread is still fine on these. We are nearing 180k at the moment, no other issues or complaints other than we have noticed the ride quality decline a tad.

So my question is this: When, if at all, should you consider replacing the shocks on a LX? And should we consider servicing the AHC as well? Any advice or guidance would be greatly appreciated!

 

[daneo]

The KO2s surely aren’t helping ride quality. (I also run KO2s)

Does the vehicle continue to undulate after hitting a bump? That would be an indicator that the shocks are in their way out. Factory shocks aren’t terribly expensive and will yield the best ride for an unladen (no steel bumpers, drawers, long range tanks) truck.

There are also some rubber pieces that could be losing their suppleness. The shock eyelets and rear shock upper mount bushings, upper control arm bushings and body mounts are the first that come to mind.

 

[cruisersandlxs]

The KO2s surely aren’t helping ride quality. (I also run KO2s)

Does the vehicle continue to undulate after hitting a bump? That would be an indicator that the shocks are in their way out. Factory shocks aren’t terribly expensive and will yield the best ride for an unladen (no steel bumpers, drawers, long range tanks) truck.

There are also some rubber pieces that could be losing their suppleness. The shock eyelets and rear shock upper mount bushings, upper control arm bushings and body mounts are the first that come to mind.

Thanks for the quick reply!
I do not feel like it excessively undulates after hitting a bump, but yes, I do feel a bit of that after hitting a speed bump of something.

Question on shock replacement: should I head to the local Lexus dealer for this work, or look for somewhere custom? I've already read a few bad "AHC service at Lexus Dealership issues" on here, so I'm starting to think I should be careful about doing anything to the AHC and stick simply with a shock replacement.

 

[tbisaacs]

The KO2s surely aren’t helping ride quality. (I also run KO2s)

Does the vehicle continue to undulate after hitting a bump? That would be an indicator that the shocks are in their way out. Factory shocks aren’t terribly expensive and will yield the best ride for an unladen (no steel bumpers, drawers, long range tanks) truck.

There are also some rubber pieces that could be losing their suppleness. The shock eyelets and rear shock upper mount bushings, upper control arm bushings and body mounts are the first that come to mind.

This is not the case on an AHC vehicle. The shocks do almost no dampening. They just control the height.

I wouldn’t replace them unless they are leaking.

If your truck is not riding smooth I would first try a fluid flush (recommended every 60k) first. If that doesn’t improve things then you likely need accumulators.

Lots of details here

LX570 AHC “Basics” - Added as sticky thread for AHC Issues

Point of this thread is to serve as a repository for 200-series AHC info, including LX570 and LC equipped with AHC (in select global markets). Let’s begin with a theory. The 200-series LC (without AHC) and the LX570 (or LC with AHC) are like New York & LA. LC “purists” are like New Yorkers...

forum.ih8mud.com

And here

LX570 AHC Globe/Accumulator Replacement

I did a walk you through step by step procedure on how to replace the accumulator globes on the Lexus LX570. This same process will work on the Lexus LX470 as well, but the components are in slightly different locations. Feel free to comment or ask any questions below. I hope this is helpful for...

forum.ih8mud.com

 

[bloc]

This is not the case on an AHC vehicle. The shocks do almost no dampening. They just control the height.

I wouldn’t replace them unless they are leaking.

If your truck is not riding smooth I would first try a fluid flush (recommended every 60k) first. If that doesn’t improve things then you likely need accumulators.

Lots of details here

LX570 AHC “Basics” - Added as sticky thread for AHC Issues

Point of this thread is to serve as a repository for 200-series AHC info, including LX570 and LC equipped with AHC (in select global markets). Let’s begin with a theory. The 200-series LC (without AHC) and the LX570 (or LC with AHC) are like New York & LA. LC “purists” are like New Yorkers...

forum.ih8mud.com

And here

LX570 AHC Globe/Accumulator Replacement

I did a walk you through step by step procedure on how to replace the accumulator globes on the Lexus LX570. This same process will work on the Lexus LX470 as well, but the components are in slightly different locations. Feel free to comment or ask any questions below. I hope this is helpful for...

forum.ih8mud.com

This is good advice.

 

[oilNgasrespektr]

What about the coils? Would the truck benefit from fresh coils on the front and rear? Are there available aftermarket coils if I were to add weight to the vehicle in the form of armor, bumpers, etc??

 

[AnyMal]

Lot of stuff you can do to augment for load, from simple to sketchy lol.

If you dont plan on lifting or adding weight, a simple globe replacement is a super easy suspension refresh that i think is a great idea @ around every 10 years of road only usage.

Like it was advised above, the shock itself likely wont have much wear if fluid was maintained.

Coils do sag though and eventually overwork the globes, so a full overhaul would entail disassembly of the struts and at that point a fresh ram with new bushings isn’t too expensive. I think very reasonable for 10 years mark to do. Like a couple grand if i recall for four corners?

Outside of that its ball joints (likely not needed) and you pretty much have a new suspension feel.

 

[tbisaacs]

What about the coils? Would the truck benefit from fresh coils on the front and rear? Are there available aftermarket coils if I were to add weight to the vehicle in the form of armor, bumpers, etc??

In the rear yes, front, not so much. Others here have added pre-load through coil spacers, spring rubbers, and pre-load lifts. However — you can add a lot of weight before this becomes a significant issue. My rig is heavy and I'm running stock coils with spring rubbers in front. AHC never complains.

 

[daneo]

Curious what does the damping in AHC systems?

 

[AnyMal]

Curious what does the damping in AHC systems?

Shock damping is the globe through gas charge (hydro-pneumatic), control damping is done through staged solenoids & internal valves, cross chassis is through matrix valve core.

 

[AnyMal]

In the rear yes, front, not so much. Others here have added pre-load through coil spacers, spring rubbers, and pre-load lifts. However — you can add a lot of weight before this becomes a significant issue. My rig is heavy and I'm running stock coils with spring rubbers in front. AHC never complains.

Adding to this that a simple sensor lift will also increase perceived (pseudo) spring rate, even though coils will actually be lifting less of the load off the shock.

 

[TeCKis300]

AHC is a very highly integrated so perhaps answering where the damping if performed may not help isolate the issue. A well understood wear item, to @tbisaacs point, is the accumulators/globes and ride often degrades with these being worn. Meaning the globes lose nitrogen pressure, or rupture, leading to less compliance and effective damping.

To the original question, I would likewise encourage changing the accumulators combined with a fluid flush.

Many of us have sourced OEM accumulators direct from Japan. Several highly rated sellers with super fast shipping.

Bring these to a dealership and have them install and do a flush. I can't speak for price directly but it should be no more than 2-3 labor hours. Many of us have done this at home in less than that time.

 

[TeCKis300]

Adding to this that a simple sensor lift will also increase perceived (pseudo) spring rate, even though coils will actually be lifting less of the load off the shock.

I'm not following? Sensor lift will generally decrease payload handling unless augmenting in some way.

 

[AnyMal]

I'm not following? Sensor lift will generally decrease payload handling unless augmenting in some way.

Yeah you are correct sorry for the wording.
It will simply firm up the ride since the lift is asking for more pressure, but indeed, inversely you are lowering the system load capability.

 

[AnyMal]

If anyone wondering what the hell were talking about, this is all what has led us to do stuff like we have to extend travel, lifted AHC, then compensate with preload to restore ride quality and damping. Welcome to the rabbit hole... LOL

 

[cruisersandlxs]

If anyone wondering what the hell were talking about, this is all what has led us to do stuff like we have to extend travel, lifted AHC, then compensate with preload to restore ride quality and damping. Welcome to the rabbit hole... LOL

Yes! Exactly what I was thinking/wondering! This is all so new to me TBH. So used to shocks, coils, UCAs, and voila, you're good to go. TBH, I'm starting to question why I got the LX? I'm assuming you all are very happy with you vehicles still?

 

[daneo]

OP, please disregard my initial comments on replacing the AHC “shocks”. My understanding of the system is not fully baked.

 

[AnyMal]

@cruisersandlxs

I realized i never answered properly either.
My OCD schedule is:

AHC fluid every 30k (about 3 years for me though)
Globes every 60K (about every 5 years) Im already overdue here but waiting on a bunch of mods im doing first. This is overkill TBH but im a ride comf stickler.
Shocks every 120k (about a decade)

Realistically, with fluid maintained, and no rock crawling and jumping, you should only need to overhaul suspension roughly once in the vehicle total lifetime.

Yes, i have my bad days (like right now my shimmy is back with a vengeance ever since my last suspension work a month or two ago) since i cant square my rear axle properly anymore.
Serp belt went way earlier than i thought it should, but was cheap and easy fix.
And my brakes are squealing like a B (my fault probably).

Otherwise happy, but want an exhaust and subtank ASAP.

 

[grinchy]

Yes! Exactly what I was thinking/wondering! This is all so new to me TBH. So used to shocks, coils, UCAs, and voila, you're good to go. TBH, I'm starting to question why I got the LX? I'm assuming you all are very happy with you vehicles still?

The LX suspension (and certain up market TLC in ROW) is different, so it requires different set of maintenance activities than a 'normal' suspension. It has a different capability envelope, because it is height adjustable and manages weight distribution as well (magic for towing).

For the most part, it's turn-key and set and forget for years at a time. This is why dealers aren't very adept at fixing it, it is very dependable and they never have to fix it. However, when it is time to fix, it is often a new skillset and it's different than what the service person knows, which leads to lots of issues. Simply following the FSM would alleviate this, but hey, who knows better than the tech . . .

In any case, the wear items are identified above - fluid and accumulators. Both are pretty easy to manage, as long as you don't do dumb stuff. Dumb stuff: run the reservoir dry and lose prime on the pump. get crap in your reservoir and clog the pump, wait too long on accumuulator replacement and the diapragm falls apart and gets junk in the fluid, which clogs the pump.

Finally, for rust prone areas, wash the rear crossmember below the frame occasionally to avoid the AHC line on top of it from sitting in a salt bath and rusting thru.

I'm really satisfied with my AHC, it give me a huge lift on the rare occasions I need it, and I can drive around in a normal height SUV the rest of the time. That is safer and better than any other solution. Because it is hydraulic (similar to brakes) and not air, it is very low maintenance and very reliable. Because the fluid volume is huge, it doesn't overheat or have the potential to overheat in demanding situations. It is not very compatible iwth aftermarket stuff, so really big lifts and other stuff aren't on the table. Though this forum is really working on that and may soon have it solved using modified stock stuff.

 

[Madtiger]

I'm really satisfied with my AHC, it give me a huge lift on the rare occasions I need it, and I can drive around in a normal height SUV the rest of the time. That is safer and better than any other solution. Because it is hydraulic (similar to brakes) and not air, it is very low maintenance and very reliable. Because the fluid volume is huge, it doesn't overheat or have the potential to overheat in demanding situations. It is not very compatible iwth aftermarket stuff, so really big lifts and other stuff aren't on the table. Though this forum is really working on that and may soon have it solved using modified stock stuff.

Even tho it is hydraulic, doesn’t AHC need air to do its thing? Isn’t there a air filter somewhere in the system? I could swear that i read someone here that fluid can get contaminated over time due to dirt getting into the system?