Suspension Problem LX470 1998
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Recently the LX has developed a problem (or maybe 2 separate ones).
1) Frequently when I stop (street driving), the car drops, and then immediately jumps back to the correct height. Usually both back and front at the same time, but sometimes one after the other.
2) On some roads, the car becomes very bouncy, similar to a shock absorber problem, (front shocks were replaced 6 months ago).
One thought I had is that the suspension system is over pressurising, maybe due to a sticking valve, and then suddenly releasing and repressurising to the correct height.
Any ideas?
email ron.thompson@sumitomocorp.co.jp
1) Frequently when I stop (street driving), the car drops, and then immediately jumps back to the correct height. Usually both back and front at the same time, but sometimes one after the other.
2) On some roads, the car becomes very bouncy, similar to a shock absorber problem, (front shocks were replaced 6 months ago).
One thought I had is that the suspension system is over pressurising, maybe due to a sticking valve, and then suddenly releasing and repressurising to the correct height.
Any ideas?
email ron.thompson@sumitomocorp.co.jp
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Don't think it's shocks, as surely then the ride would be the same all the time.
I decided it was either a sticking valve in the suspension hydraulics, or a computer problem.
Never did solve it, and sold the car.
Hope you have more luck than me!
Ron
I decided it was either a sticking valve in the suspension hydraulics, or a computer problem.
Never did solve it, and sold the car.
Hope you have more luck than me!
Ron
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I had the same problem, here are some bits and pieces from the IH8MUD forums, It is almost one of the most helpful sites for your LX470.
Good information! Ben, just wanted to clear up something. You refer to "Accumulators" but do you really mean "Actuators" (Damping Force Actuator). See link below. Just don't want anybody to special order the wrong part.
I have read good things about Keith Bowers at B&B Suspensions. He rebuilds the actuators at a very reasonable price ($175/ea). You can reach him at: kebowers47@hotmail.com
http://forum.ih8mud.com/attachment.p...id=36919&stc=1
you are correct in that the whole assy is called the actuator. The piece I'm referring to is the big ball piece on the end of the actuator. This is the part that actually fails, it is the part that contains the nitrogen and the diaphragm. I have never seen the actual actuator fail, or one of the pumps for that matter.
Thanks for pointing that out.
Good information! Ben, just wanted to clear up something. You refer to "Accumulators" but do you really mean "Actuators" (Damping Force Actuator). See link below. Just don't want anybody to special order the wrong part.
I have read good things about Keith Bowers at B&B Suspensions. He rebuilds the actuators at a very reasonable price ($175/ea). You can reach him at: kebowers47@hotmail.com
http://forum.ih8mud.com/attachment.p...id=36919&stc=1
you are correct in that the whole assy is called the actuator. The piece I'm referring to is the big ball piece on the end of the actuator. This is the part that actually fails, it is the part that contains the nitrogen and the diaphragm. I have never seen the actual actuator fail, or one of the pumps for that matter.
Thanks for pointing that out.
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Bad globes are the main reason for bounciness, but not why the vehicle would drop and change back to normal. You can perform the low-high AHC test and read the change in the number of gradations on the AHC resevoir. It should be at least 7. If less, the globes are bad. Globes go bad if you use the wrong fluid in the resevoir (must use Toyota AHC fluid, not hydraulic/brake fluid). The wrong fluid dissolves the membrane in the globes (I believe they cannot be recharged if this happens). Not changing the fluid collects excessive water in the system (just like brakes), and it could rust in the inside.
Is your car heavily loaded? There is a max weight tolerance (around 1200 lbs, including passengers) before the AHC reverts to low mode at all speeds. The AHC is one of the most often overlooked item in terms of maintenance, as not many people (even the service managers) understand it. The service manager at my dealer tried to tell me the height control unit was air actuated and could not be bled, and that only the 4 globes could be bled. Since I have the 2000 pages of factory manuals that tell you how to bleed them, I knew he was flat-out clueless. It seems most Lexus/Toyota service managers are clueless, so you gotta research what's really going on and specifically tell them what to do (ie, bleed 4 corner actuators plus the height accumulator).
Is your car heavily loaded? There is a max weight tolerance (around 1200 lbs, including passengers) before the AHC reverts to low mode at all speeds. The AHC is one of the most often overlooked item in terms of maintenance, as not many people (even the service managers) understand it. The service manager at my dealer tried to tell me the height control unit was air actuated and could not be bled, and that only the 4 globes could be bled. Since I have the 2000 pages of factory manuals that tell you how to bleed them, I knew he was flat-out clueless. It seems most Lexus/Toyota service managers are clueless, so you gotta research what's really going on and specifically tell them what to do (ie, bleed 4 corner actuators plus the height accumulator).
Last edited by V8_Fan; 11-30-06 at 06:44 AM.
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I just went through the exact same scenario. It was the 4 accumulators, replaced them and has been great since. Keith Bowers did the rebuild and he guarantees them. Most people will tell you that the wrong fluid is the always the problem but the 900 psi nitrogen pad on the backside of the membrane bleeds over in to the SN10 oil naturally. Kinda depends on the quality of the membrane they used that day. There is a fifth accumulator for ride height but that almost never goes bad. If it does it is a pain to remove. The accumulators screw right off all you need is a open end wrench from Sears and grind it thin....
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No. The only 2" lift that allows you to maintain normal AHC operation is the Keepslant lift. The key is you need to extend not only the AHC sensors, but the shocks using shock extension brackets and stabilizer extensions. The kit also comes w/ a longer rear lateral rod, since any lift will cause the rear axle to pivot forward. You also need to drop the front diff an inch (kit comes w/ a new IFS crossmember that lowers the diff).
BTW, I think the reason why the vehicle would drop as soon as you stopped, then raise back up, is the damper globe membranes were all shot (no nitrogen left). When you stop, the hydraulic pressure increases momentarily, but the membrane has no nitrogen on one side to absorb that increase, so the pressure exceeds the limit which causes the AHC to drop the vehicle into low as if you overloaded it. But after a few seconds, the pressure equalizes and falls below that limit and the AHC realizes it's too low and raises back to N.
BTW, I think the reason why the vehicle would drop as soon as you stopped, then raise back up, is the damper globe membranes were all shot (no nitrogen left). When you stop, the hydraulic pressure increases momentarily, but the membrane has no nitrogen on one side to absorb that increase, so the pressure exceeds the limit which causes the AHC to drop the vehicle into low as if you overloaded it. But after a few seconds, the pressure equalizes and falls below that limit and the AHC realizes it's too low and raises back to N.
Last edited by V8_Fan; 06-23-07 at 09:47 PM.
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Hi jmd93,
To change the actuators, the dealer will charge from $400 to $600 just to change one or all actuators. Front actuators is around 539 each and rear 586 each. This depend where you are. I changed this by myself and it is not that bad. It took me about 1 1/2 hours. I bought front and rear from Keith. http://yhst-76231485467161.stores.yahoo.net/
To change the actuators, the dealer will charge from $400 to $600 just to change one or all actuators. Front actuators is around 539 each and rear 586 each. This depend where you are. I changed this by myself and it is not that bad. It took me about 1 1/2 hours. I bought front and rear from Keith. http://yhst-76231485467161.stores.yahoo.net/
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Definitely need to replace the accumulators. This is a common problem with most LX470's. I have actually had some of my customers describe their car as riding like a pogo stick. Funny how the customer is right!!!. As far as the front lower than the rear, it sound as if one/all of your height control sensors may be rusted on the inside. If the vehicle has not been in a accident(thus resulting in bent height control sensors) it is very possible they are loosing connection at times on the inside. Highly reccomend having them looked at by lexus professionals, due to the fact that with our scan tool we can do a heck of a lot more diagnosis on the sensors.
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I am having two problems one is when I stop at a drive through the car (2000 LX 470) the car raises and lowers back to N. The lady at the drive through get a charge out of it but I don't. It only happens sometimes. The other problem and my biggest concern in the VSC TRAC, VSC OFF and the engine light just came on and the car acts like it is starving for fuel at idle. When I step on it it smooths out until I let off the gas. Does anyone have a clue?