LX470 Bouncing and Jarring Ride (FIXED!) (1 Viewer)

[goldLX]

Hi all, first time posting on here. I’m an owner of a 99’ LX470 with 156K wonderful miles.

However, we are having a horrible time with our other 01’ LX470, 164K. As the title states, our vehicle is experiencing a bouncing and jarring ride. I’m mildly familiar with how the suspension works, but far from an expert when it comes to diagnosing/fixing the problem.

I have searched high and low on these forums, but nothing sounds the same as our issue. The car raises and lowers fairly normal, maybe a little more aggressive compared to my other LX. It raises ok, neutral ok and lowers ok. No blinking raise control or anything like that. Not stuck in low etc.

The ride is bad, really bad over any dip or sudden movement in the pavement. It will dodge, duck, dip, dive and dodge, all over the place. Over smooth road, everything seems normal. Car has nice Michelin tires on and fresh alignment. It has been like this for over 10k miles. Now I’m finally tired of it.

We are located in southwest Florida. Haven’t taken it to the dealer yet, but am seeking professional help to fix this. Has anyone fixed an issue like this?

Thank you for any help!

 

[suprarx7nut]

Have you inspected the following?

1. Leaky rams (shocks). Some weeping oil or oil residue is normal, dripping fluid is not.
2. Neutral pressures
3. How many gradations does the fluid move in the under-hood reservoir from L to H?

 

[nukegoat]

bad globes

 

[trdcorolla]

Have you inspected the following?

1. Leaky rams (shocks). Some weeping oil or oil residue is normal, dripping fluid is not.
2. Neutral pressures
3. How many gradations does the fluid move in the under-hood reservoir from L to H?

bad globes

Both are right, set your heights, then set your pressures (this should stop any weeping oil from the shocks) and replace the globes. My LX with bad globes raised/lowered faster than the new good globes. My pressures didn't change after replacing the globes.

 

[boca1]

Both are right, set your heights, then set your pressures (this should stop any weeping oil from the shocks) and replace the globes. My LX with bad globes raised/lowered faster than the new good globes. My pressures didn't change after replacing the globes.

and how is the ride now?

 

[goldLX]

Sorry, but what exactly do you mean by check pressures?

 

[goldLX]

I would say about 6 or so graduations from H-L.

 

[flintknapper]

I would say about 6 or so graduations from H-L.

Globes are likely shot. By 'check pressures' they mean compare (and adjust) the front to rear pressures. There are specs for this.

 

[suprarx7nut]

Sorry, but what exactly do you mean by check pressures?

I would say about 6 or so graduations from H-L.

You'll need techstream to check pressures. The front and rear have specified pressures. If the pressure is off, the system can't properly compensate.

6 is too few. The globes are probably toast. It's around $1k for a fullset of new globes. They're the common wear item in the AHC system.

7 is about the minimum and if I recall correctly, 9 and up is what you want.

 

[Flipped Bezel]

I would say about 6 or so graduations from H-L.

I'm pretty sure for a globe health check you need to verify the graduations by going from low to high...Not the other way around. You may want to check it again to confirm your results.

 

[SlowBuild]

I don’t think it should matter L-H or H-L, it’s just fluid displacement. When you get around to measuring pressures you’ll have to read them L-N. But you’ll need to study the AHC thread before you get to that.

Everyone uses techstream but I didn’t want to deal with finding an old laptop and installing the program it seemed like a hassle to me. I got the iCarsoft TYT ii from Amazon. Handheld unit that’s been really good and easy for reading pressures, scanning codes etc. It was about $130 but so easy to use and saves me the trouble of dealing with an ancient laptop, plus it’s compact and easy to stow away for trips. Could be a good alternative for you, I’m surprised I don’t hear more people using it. There’s a thread somewhere here about it.

Even if you end up replacing globes you’ll still want to be able to dial in your pressures at home. In my experience service departments don’t have the foggiest idea about this.

 

[goldLX]

Thanks for all your help. Would it be helpful at all to check and set the pressures with that tool first to see if that will fix it? Is replacing the globes something a 3rd party shop can do correctly? Is the dealer the safest way about this? DIY possible? Thank you.

 

[trdcorolla]

and how is the ride now?

Ride is good 90% of the time. I don't miss my Icon Stage 2 suspension I had on my 4th gen 4Runner (sometimes I do miss a lift though, haha). There is one issue though, it seems on certain types of roads, like certain types of small cracks/repaired cracks on the road the AHC can't absorb. It could be my LT tires though. I refurbed my swaybar bushings. Visually my rear upper and lower control arm and panhard bushings look okay, no major cracks. Those don't be hard to replace when the time comes. I've read some here are replacing the AHC shock bushings, not sure I wanna get that deep since it rides so nice right now.

 

[suprarx7nut]

Thanks for all your help. Would it be helpful at all to check and set the pressures with that tool first to see if that will fix it? Is replacing the globes something a 3rd party shop can do correctly? Is the dealer the safest way about this? DIY possible? Thank you.

The pressures are changed by replacing worn out springs or changing to a higher spring rate if you have armor or other added weight in the car. There is no pressure you can "tune" with the interface. They are what they are. To change it, you have to change out suspension parts. *Exception being torsion bar tweaks if only minor adjustments are needed*

A Lexus dealer is a good starting point, but you might ask if you can have only the master tech touch it. When I worked at Toyota they would grant people to have only the master tech look at the car upon request. It's likely some of the techs at a dealer have never dealt with an LX AHC system.

I would fear the service writer more than the tech.

 

[SlowBuild]

The pressures are changed by replacing worn out springs or changing to a higher spring rate if you have armor or other added weight in the car. There is no pressure you can "tune" with the interface. They are what they are. To change it, you have to change out suspension parts.

A Lexus dealer is a good starting point, but you might ask if you can have only the master tech touch it. When I worked at Toyota they would grant people to have only the master tech look at the car upon request. It's likely some of the techs at a dealer have never dealt with an LX AHC system.

I would fear the service writer more than the tech.

You can crank the torsion bars to lower the front pressures without replacing any hardware. This will also have a slight affect on rear pressures. This will help comfort and longevity some but likely will be hard to get in spec without new springs. Might buy you some time before investing. If you only get 6 ticks on the reservoir L-H then you’ll need globes eventually if you keep the system.

Theoretically, I suppose you could also lower the height sensors (reverse AHC lift) to buy back some time and drop pressures a bit but seems counterproductive, especially if your globes are shot. I’ve never heard of anyone doing this and I’m not recommending it.

 

[suprarx7nut]

You can crank the torsion bars to lower the front pressures without replacing any hardware. This will also have a slight affect on rear pressures. This will help comfort and longevity some but likely will be hard to get in spec without new springs. Might buy you some time before investing. If you only get 6 ticks on the reservoir L-H then you’ll need globes eventually if you keep the system.

Theoretically, I suppose you could also lower the height sensors (reverse AHC lift) to buy back some time and drop pressures a bit but seems counterproductive, especially if your globes are shot. I’ve never heard of anyone doing this and I’m not recommending it.

Absolutely right, thank you. Though I think if you have armor you need to change out the torsion bar because cranking it doesn't increase spring rate.

For stock rig adjustment, though, agreed. A T-bar adjustment is probably a good first approach.

 

[Dannyboy lx470]

I feel mine usually on speed humps the most.

 

[boca1]

Ride is good 90% of the time. I don't miss my Icon Stage 2 suspension I had on my 4th gen 4Runner (sometimes I do miss a lift though, haha). There is one issue though, it seems on certain types of roads, like certain types of small cracks/repaired cracks on the road the AHC can't absorb. It could be my LT tires though. I refurbed my swaybar bushings. Visually my rear upper and lower control arm and panhard bushings look okay, no major cracks. Those don't be hard to replace when the time comes. I've read some here are replacing the AHC shock bushings, not sure I wanna get that deep since it rides so nice right now.

Well that would be how I would describe my ride, great on everything but expansion joints and small cracks. Thanks

 

[goldLX]

Bumping this thread.

Is this a “dealer only” kind of job to replace the globes etc. Or are there reputable 3rd party shops that are familiar with this kind of replacement? I’m located on the east coast btw. Thanks!

 

[hickuptruck]

Bumping this thread.

Is this a “dealer only” kind of job to replace the globes etc. Or are there reputable 3rd party shops that are familiar with this kind of replacement? I’m located on the east coast btw. Thanks!

Incredibly easy. Easier than changing a regular suspension setup. No, third party shops and even Lexus dealers aren't knowledge able. Literally set your LX to low, get the car supported, then use a chain wrench to take off the globe. Do this 4 corners, put new fluid in, and bleed. If you can bleed brakes, you can change AHC globes