Rear air strut replacement with new Arnott aftermarket struts
10-14-18, 03:15 PM
#1
Lexus Test Driver
Thread Starter
Rear air strut replacement with new Arnott aftermarket struts
Rear strut replacement, Arnott Industries part number: AS-2856
Strut replacement is a breeze, right? I mean, pfffft, those of us who DIY have probably done it at least half a dozen times over the years, and it could not be more straightforward.
Get in the trunk, pull back carpet/padding, unbolt the top of the strut, get out, jack up that corner, jackstand placed so the suspension is at full droop, unbolt the bottom bolt, remove, replace, button it back up.
45 minutes, max, for the first side. Second side should be 20 minutes, 'cause now you know what tricks the car had waiting for you and you have all tools/equipment at the ready. In our case, air suspension, so add another 20 minutes for actuators/air lines, no big deal.
Hoooo-buddy, this is different.
First, remove the back seat...all of it. Not the end of the world, but it has to live elsewhere, temporarily. Then there's partial removal of the parcel shelf. Again, no big deal, but you just know it's going to bend/break when you're messing with it.
Removing the old ones isn't bad. However...getting the new ones in that same space, oriented correctly & in the mounting holes, well...that's something else, all together.
The new struts ship with air in them, so they're fully-extended. This makes for a significant challenge to get them into place. It took a floor jack, a long pry bar, a block of 2x4 and a small sledgehammer, and much cursing. I tried to compress them, but no, that's not going to happen. Arnott wouldn't tell me how to bleed the air off them, either. Regardless, they need to ship with a plastic packing tie-wrap, like what you find on large boxes, compressed about 2". it's not going to damage anything, as that's how it will spend the rest of its life, compressed a bit. This way, you can slide them into place after raising the suspension a teeny bit, bolt it all up, then snip the tie and they extend.
Once you get the physical part done, then comes leveling the car...via the suspension's computer and the adjustment links at each corner. Sigh...this made me want to club baby seals with kittens, it's that frustrating/infuriating.
Each corner has a sensor, yeah, and in theory, you shouldn't have to adjust it, but it's always going to be required if you change anything. The new Arnott struts, and this is a problem for some, they have about 1.5" less travel than OEM. They bottom-out much sooner than the original ones, so if, like me, you lowered your car a little, you have to undo that.
Here's where it gets ugly. You'll probably want to raise the nose a bit, too, so the car is level, however, this is the trying aspect of it.
You'd expect each corner to move a bit up or down, depending on how the linkage is adjusted between the sensor's rheostat and it's hard link to the suspension, right?
Nope, go fish.
First, my car started sky high. The only thing different was the new struts, so something is obviously out-of-whack. No problem, I'll just adjust the corners back to normal height.
Fast-forward a couple of weeks...needed a replacement strut for a defective one, that took close to 10 days (UPS ground shipping and they would not send a replacement out until they received mine (this is bothersome), plus there was a holiday involved and two weekends. Also, this was after messing with trying to get it level for a few days. Like I said, it was brutally hot with the car idling in the garage, in August, in Texas...this getting older body can handle truly hot for only so long.
The defect was an air leak on one side, after putting it all back together (rear seat and everything), however, getting the car to sit correctly was a challenge I did not expect.
There are the manual, physical adjustments at each corner's height sensor, simple. However...the computer also tweaks height, too, but it works by its own, mysterious rules. I started at the back, because I had both elevated a bit as there was a lack of damping due to leaks in the damping aspect of the struts. No problem, I put them at about the halfway point of the adjustment range. Fired her up, hit 'height high', counted to 20, pressed it again, watched it settle down, and wait...why is the nose on the ground?! It's completely deflated.
No problem, I'll just hit the compressor with some Techstream control, raise that sucker up, and put it on jacks to adjust the front sensors.
Nope, the compressor ran for about 2-3 seconds then stopped.
The compressor relay is good, the socket's connections test fine, no blown fuses, nothing. I remove the compressor to bench test it. It tests 100%. Tried a different relay in that socket, still no go. I tracked that bad connection down for two days, never did find it. One time, the relay clicked, and the compressor started working again.
By this time, I'd just driven up on to a couple of 2x4 scraps, so I could get the floor jack under the rocker panel. (tip: hockey pucks, with a groove cut into them, are perfect for unibody protection when used as a pad on the jack's lifting surface)
This wasted a solid two days, removing the compressor, testing it, then after putting it back, figuring out why it would not turn on.
I bottomed the sensors out, then increased 'height' until they read the middle of the voltage they should, 2.33-2.35V. Now, at least, I have a baseline.
I go on to discover, if you adjust the RF corner just a little, the car may go full-on Looney Tunes and start messing with the other three corners. Then again, maybe not.
So, you want to lower the LF 22mm, but that's outside the computer's adjustment, therefore, you manually make the sensor's adjustment link a couple of turns shorter. Start her up, height high <on>, let it rise a bit, height high <off>, break out your tape measure and start measuring the corners for the umpteenth time.
This is evil...adjusting the RF corner down 22 mm resulted in the LF dropping about 15 (which was expected, though not that much), the LR going up a little, and the LR going up a lot.
Whut?!
Other times, it does exactly what you intended. There's no rhyme or reason, best I can tell, and I've spent many hours working on and trying to figure out how it works.
I get the RF to where I want it, and from then on, I adjusted in very, very small increments, let the car find it's height, then tweaked that corner, again, until it was exactly where I wanted it, middle of the wheel well's bottom edge metal lip to the ground, 715 mm.
Now, however, the LF is at 730, LR 745, and RR 750.
I adjusted the LF, got it within 5 mm, that's fine. The RF is now 711 mm, which should work for testing, at least (it turns out to be a bit low, but sub-10 mm adjustments are "simple" and "quick" using the computer).
Time for the rears.
They're easier to adjust, physically, but they're not any more pleasant to actually change. You have to do this with the engine running, or the compressor will not run. and the rear damper linkages are such, your arm winds up an inch from the muffler...maybe. Furthermore, there's barely room for one arm in that area, much less two, and it's difficult to tighten the locknut without the entire thing getting out-of-adjustment. After several hours of engine idling, getting up and down off the garage floor countless dozens of times, I'm close enough, it's drivable.
Oh, and then you have the problem of "the adjuster is in the PERFECT spot, but as soon as you touch it with a wrench to tighten, it moves all the way to the bottom, taking most of the access you had to it, with it as the system bleeds off air in a hurry".
Drove it to work, and sure enough, there winds up being about a 15 mm difference across the corners. I can hear the RR bottoming, and I can feel the RF isn't quite right, and it's obvious, to me, the car is not level.
Got home, another hour leveling it, driving around the neighborhood between adjustments, and this time, I'm down to using the Techstream to get fine adjustments. Drove to work the next day, it looks good. On the way home, I can hear the RR bottom on a couple of sharp bumps, so that needs to come up probably 5 mm. Regardless, I see why installation costs what it does. Not only is getting the struts in the car remarkably difficult, between the manual adjustment and computerized adjustment, the manual computer controls, it's brutal. Then throw in the fact the car does what it thinks is right, even if you have it dead-on level. Part of it is, I think, the 'height offset' must be -0- before you start, or else you're never going to beat it. I eventually tried this, and while it was better, it still wasn't the way I wanted it.
If anything, I wanted a few millimeters more in the rear's height, so the car looks even or a tiny bit raked. Plus, the new struts need to start from a higher position because less travel.
One thing which helped, greatly, and this was near the end, when I thought I was going to lose my mind...I asked my Lovely Wife to come out to the garage and tell me when the LF and RF heights showed, in Techstream, to be the same. Took a bit of fiddling, but got them both to 10.6-10.8 MM. Had to do more adjusting from there, but at least I knew I could get them even. Her watching the readout confirmed, moving one corner can cause all the others to adjust, so it's incredibly difficult to get all four corners where you want them since the computer is fighting you to some degree.
Also, in Techstream...using Height Offset, when entering values, the values really don't matter, but what does matter is, you have 20 mm to play with, supposedly. I had mine up to 25 mm at one point. Anyway, to move the car down, put a slightly larger number in the measured value versus the specification value. IOW, it's the reverse of what you might think, and that's because of how it's measured. Toyota wants the measurement between the centerlines of two bolts, but this results in a larger number lowering the car. At least I think that's what I eventually determined. I definitely remember it seeming backward, until I thought about what the computer thinks I'm supposed to be measuring.
The new Arnott struts work fine, and at $683 each, shipped, with doing the installation myself, I didn't spend about $3,650. Was it worth it? Not by week five, it wasn't, but I was in for a penny, in for a pound at that point.
I'm more than a bit miffed they don't have the same range of travel the OEM ones do, but I may investigate tweaking this in the future. The damping adjustment rod does what it's supposed to, though I will admit, the new dampers are stiff enough that, in combination with the front struts having 125K on them, the car feels a little like a 70s land yacht with air shocks for towing a boat/camper. It doesn't bother me...makes me smile a little, actually, as I've owned cars just like that...and it's still plenty cushy.
This is probably a bit rambling, but I lost the first copy due to a power outage, and this one became a novel after writing it up once, already.
I will attempt to answer any and all questions surrounding this procedure and any tricks I came across.
FWIW, the other stuff...air lines, damper actuators, that stuff is all super-simple. Be careful with it all...the air lines seem trickier than they are, initially, and the actuators have to go back with the same orientation as when they were removed, but otherwise, it's straightforward. It's getting the strut mounted, specifically the bottom mount, is brutal, and leveling is Ph.D. level frustrating.
A note...you'll need six new bolts for the actuator covers, because the new top strut bolts are a different size than OEM. I wish I could remember which ones they are, but I think I erased that note (whiteboard in the garage...and it's came in remarkably handy for this job, alone).
Strut replacement is a breeze, right? I mean, pfffft, those of us who DIY have probably done it at least half a dozen times over the years, and it could not be more straightforward.
Get in the trunk, pull back carpet/padding, unbolt the top of the strut, get out, jack up that corner, jackstand placed so the suspension is at full droop, unbolt the bottom bolt, remove, replace, button it back up.
45 minutes, max, for the first side. Second side should be 20 minutes, 'cause now you know what tricks the car had waiting for you and you have all tools/equipment at the ready. In our case, air suspension, so add another 20 minutes for actuators/air lines, no big deal.
Hoooo-buddy, this is different.
First, remove the back seat...all of it. Not the end of the world, but it has to live elsewhere, temporarily. Then there's partial removal of the parcel shelf. Again, no big deal, but you just know it's going to bend/break when you're messing with it.
Removing the old ones isn't bad. However...getting the new ones in that same space, oriented correctly & in the mounting holes, well...that's something else, all together.
The new struts ship with air in them, so they're fully-extended. This makes for a significant challenge to get them into place. It took a floor jack, a long pry bar, a block of 2x4 and a small sledgehammer, and much cursing. I tried to compress them, but no, that's not going to happen. Arnott wouldn't tell me how to bleed the air off them, either. Regardless, they need to ship with a plastic packing tie-wrap, like what you find on large boxes, compressed about 2". it's not going to damage anything, as that's how it will spend the rest of its life, compressed a bit. This way, you can slide them into place after raising the suspension a teeny bit, bolt it all up, then snip the tie and they extend.
Once you get the physical part done, then comes leveling the car...via the suspension's computer and the adjustment links at each corner. Sigh...this made me want to club baby seals with kittens, it's that frustrating/infuriating.
Each corner has a sensor, yeah, and in theory, you shouldn't have to adjust it, but it's always going to be required if you change anything. The new Arnott struts, and this is a problem for some, they have about 1.5" less travel than OEM. They bottom-out much sooner than the original ones, so if, like me, you lowered your car a little, you have to undo that.
Here's where it gets ugly. You'll probably want to raise the nose a bit, too, so the car is level, however, this is the trying aspect of it.
You'd expect each corner to move a bit up or down, depending on how the linkage is adjusted between the sensor's rheostat and it's hard link to the suspension, right?
Nope, go fish.
First, my car started sky high. The only thing different was the new struts, so something is obviously out-of-whack. No problem, I'll just adjust the corners back to normal height.
Fast-forward a couple of weeks...needed a replacement strut for a defective one, that took close to 10 days (UPS ground shipping and they would not send a replacement out until they received mine (this is bothersome), plus there was a holiday involved and two weekends. Also, this was after messing with trying to get it level for a few days. Like I said, it was brutally hot with the car idling in the garage, in August, in Texas...this getting older body can handle truly hot for only so long.
The defect was an air leak on one side, after putting it all back together (rear seat and everything), however, getting the car to sit correctly was a challenge I did not expect.
There are the manual, physical adjustments at each corner's height sensor, simple. However...the computer also tweaks height, too, but it works by its own, mysterious rules. I started at the back, because I had both elevated a bit as there was a lack of damping due to leaks in the damping aspect of the struts. No problem, I put them at about the halfway point of the adjustment range. Fired her up, hit 'height high', counted to 20, pressed it again, watched it settle down, and wait...why is the nose on the ground?! It's completely deflated.
No problem, I'll just hit the compressor with some Techstream control, raise that sucker up, and put it on jacks to adjust the front sensors.
Nope, the compressor ran for about 2-3 seconds then stopped.
The compressor relay is good, the socket's connections test fine, no blown fuses, nothing. I remove the compressor to bench test it. It tests 100%. Tried a different relay in that socket, still no go. I tracked that bad connection down for two days, never did find it. One time, the relay clicked, and the compressor started working again.
By this time, I'd just driven up on to a couple of 2x4 scraps, so I could get the floor jack under the rocker panel. (tip: hockey pucks, with a groove cut into them, are perfect for unibody protection when used as a pad on the jack's lifting surface)
This wasted a solid two days, removing the compressor, testing it, then after putting it back, figuring out why it would not turn on.
I bottomed the sensors out, then increased 'height' until they read the middle of the voltage they should, 2.33-2.35V. Now, at least, I have a baseline.
I go on to discover, if you adjust the RF corner just a little, the car may go full-on Looney Tunes and start messing with the other three corners. Then again, maybe not.
So, you want to lower the LF 22mm, but that's outside the computer's adjustment, therefore, you manually make the sensor's adjustment link a couple of turns shorter. Start her up, height high <on>, let it rise a bit, height high <off>, break out your tape measure and start measuring the corners for the umpteenth time.
This is evil...adjusting the RF corner down 22 mm resulted in the LF dropping about 15 (which was expected, though not that much), the LR going up a little, and the LR going up a lot.
Whut?!
Other times, it does exactly what you intended. There's no rhyme or reason, best I can tell, and I've spent many hours working on and trying to figure out how it works.
I get the RF to where I want it, and from then on, I adjusted in very, very small increments, let the car find it's height, then tweaked that corner, again, until it was exactly where I wanted it, middle of the wheel well's bottom edge metal lip to the ground, 715 mm.
Now, however, the LF is at 730, LR 745, and RR 750.
I adjusted the LF, got it within 5 mm, that's fine. The RF is now 711 mm, which should work for testing, at least (it turns out to be a bit low, but sub-10 mm adjustments are "simple" and "quick" using the computer).
Time for the rears.
They're easier to adjust, physically, but they're not any more pleasant to actually change. You have to do this with the engine running, or the compressor will not run. and the rear damper linkages are such, your arm winds up an inch from the muffler...maybe. Furthermore, there's barely room for one arm in that area, much less two, and it's difficult to tighten the locknut without the entire thing getting out-of-adjustment. After several hours of engine idling, getting up and down off the garage floor countless dozens of times, I'm close enough, it's drivable.
Oh, and then you have the problem of "the adjuster is in the PERFECT spot, but as soon as you touch it with a wrench to tighten, it moves all the way to the bottom, taking most of the access you had to it, with it as the system bleeds off air in a hurry".
Drove it to work, and sure enough, there winds up being about a 15 mm difference across the corners. I can hear the RR bottoming, and I can feel the RF isn't quite right, and it's obvious, to me, the car is not level.
Got home, another hour leveling it, driving around the neighborhood between adjustments, and this time, I'm down to using the Techstream to get fine adjustments. Drove to work the next day, it looks good. On the way home, I can hear the RR bottom on a couple of sharp bumps, so that needs to come up probably 5 mm. Regardless, I see why installation costs what it does. Not only is getting the struts in the car remarkably difficult, between the manual adjustment and computerized adjustment, the manual computer controls, it's brutal. Then throw in the fact the car does what it thinks is right, even if you have it dead-on level. Part of it is, I think, the 'height offset' must be -0- before you start, or else you're never going to beat it. I eventually tried this, and while it was better, it still wasn't the way I wanted it.
If anything, I wanted a few millimeters more in the rear's height, so the car looks even or a tiny bit raked. Plus, the new struts need to start from a higher position because less travel.
One thing which helped, greatly, and this was near the end, when I thought I was going to lose my mind...I asked my Lovely Wife to come out to the garage and tell me when the LF and RF heights showed, in Techstream, to be the same. Took a bit of fiddling, but got them both to 10.6-10.8 MM. Had to do more adjusting from there, but at least I knew I could get them even. Her watching the readout confirmed, moving one corner can cause all the others to adjust, so it's incredibly difficult to get all four corners where you want them since the computer is fighting you to some degree.
Also, in Techstream...using Height Offset, when entering values, the values really don't matter, but what does matter is, you have 20 mm to play with, supposedly. I had mine up to 25 mm at one point. Anyway, to move the car down, put a slightly larger number in the measured value versus the specification value. IOW, it's the reverse of what you might think, and that's because of how it's measured. Toyota wants the measurement between the centerlines of two bolts, but this results in a larger number lowering the car. At least I think that's what I eventually determined. I definitely remember it seeming backward, until I thought about what the computer thinks I'm supposed to be measuring.
The new Arnott struts work fine, and at $683 each, shipped, with doing the installation myself, I didn't spend about $3,650. Was it worth it? Not by week five, it wasn't, but I was in for a penny, in for a pound at that point.
I'm more than a bit miffed they don't have the same range of travel the OEM ones do, but I may investigate tweaking this in the future. The damping adjustment rod does what it's supposed to, though I will admit, the new dampers are stiff enough that, in combination with the front struts having 125K on them, the car feels a little like a 70s land yacht with air shocks for towing a boat/camper. It doesn't bother me...makes me smile a little, actually, as I've owned cars just like that...and it's still plenty cushy.
This is probably a bit rambling, but I lost the first copy due to a power outage, and this one became a novel after writing it up once, already.
I will attempt to answer any and all questions surrounding this procedure and any tricks I came across.
FWIW, the other stuff...air lines, damper actuators, that stuff is all super-simple. Be careful with it all...the air lines seem trickier than they are, initially, and the actuators have to go back with the same orientation as when they were removed, but otherwise, it's straightforward. It's getting the strut mounted, specifically the bottom mount, is brutal, and leveling is Ph.D. level frustrating.
A note...you'll need six new bolts for the actuator covers, because the new top strut bolts are a different size than OEM. I wish I could remember which ones they are, but I think I erased that note (whiteboard in the garage...and it's came in remarkably handy for this job, alone).
Last edited by mckellyb; 10-19-18 at 11:28 PM. Reason: typos
The following users liked this post:
yyymmm31 (10-14-18)
10-15-18, 12:09 AM
#4
Lexus Test Driver
Thread Starter
Fort Worth, SW side of town.
10-15-18, 08:37 AM
#5
When I tried leveling my fronts using the external linkages I also noticed how screwed up the system is and I posted about it.
if one corner is lower thwn another the computer seems to go haywire and gets confused , it keeps trying to adjust but it seems incapable of doimg so.
It would completely deflate the bags even though I was only adjusting in very minimal increments
I.honestly wish I never bought one with air but at least havent had any breakdowns or real issues yet .
good luck on sorting it out , sounds like a nightmare
if one corner is lower thwn another the computer seems to go haywire and gets confused , it keeps trying to adjust but it seems incapable of doimg so.
It would completely deflate the bags even though I was only adjusting in very minimal increments
I.honestly wish I never bought one with air but at least havent had any breakdowns or real issues yet .
good luck on sorting it out , sounds like a nightmare
10-16-18, 08:55 AM
#7
Former Sponsor
Full deflation is not recommended due to the straight sleeves used within the construction of our strut assemblies. If compressed while deflated the sleeves will “bunch” inside of the can causing a very poor ride quality and rapid failure. Also note that our passive shock absorbers can not be manipulated like the originals via the actuator.
http://arnottinfo.com/manuals/web/Re...x?part=AS-2856
The following users liked this post:
sha4000 (10-16-18)
Trending Topics
10-16-18, 03:25 PM
#8
Lexus Test Driver
10-17-18, 11:04 AM
#10
Former Sponsor
No, Arnott does not offer active (more accurately semi-active) struts for the LS 460. Arnott's passive struts include a brand new custom valved shock along with all new top and bottom mounts, seals, bump stop, protective aluminum cans, etc. These struts provide a great ride along with a fully functional air spring which will work with the vehicle's self-leveling functionality to provide the comfort and luxury of air suspension but without the OE price. We did look into remanufacturing these struts but Arnott R&D was not happy with the result.
Link to Arnott Products for the LX 460
Link to Arnott Products for the LX 460
10-19-18, 11:32 PM
#11
Lexus Test Driver
Thread Starter
Doug,
So the rod inside the central tube, the one which looks/moves just like the OEM damper, is purely for show and actually does nothing?!
Why have it, then?
I'm far from pleased about this, as the copy description, to me, reads as if it has similar computer-controlled adjustability to OEM. I mean, there's no reason I can see to include this shaft if it's not connected to anything. The actuators will spin whether they're touching anything or not, and they can't possibly require support from below.
Looks like I'll hunt for a pair of new OEM ones, at some point, because this is one of the things I really like about the air system...the ability to have it be firm or soft, depending on what you choose.
This also explains why my LS 460 feels much like a '73 Coupe DeVille set up to tow a 7K lb. travel trailer. When set to 'comfort', the nose is super 70s soft while the rear is air-shock firm.
At least it's drivable for as long as need be. However, I'm pissed off about this not actually being adjustable. No, it's not that as much as it's not mentioned anywhere, "this damper has fixed settings and is not variable like the OEM unit".
So the rod inside the central tube, the one which looks/moves just like the OEM damper, is purely for show and actually does nothing?!
Why have it, then?
I'm far from pleased about this, as the copy description, to me, reads as if it has similar computer-controlled adjustability to OEM. I mean, there's no reason I can see to include this shaft if it's not connected to anything. The actuators will spin whether they're touching anything or not, and they can't possibly require support from below.
Looks like I'll hunt for a pair of new OEM ones, at some point, because this is one of the things I really like about the air system...the ability to have it be firm or soft, depending on what you choose.
This also explains why my LS 460 feels much like a '73 Coupe DeVille set up to tow a 7K lb. travel trailer. When set to 'comfort', the nose is super 70s soft while the rear is air-shock firm.
At least it's drivable for as long as need be. However, I'm pissed off about this not actually being adjustable. No, it's not that as much as it's not mentioned anywhere, "this damper has fixed settings and is not variable like the OEM unit".
10-20-18, 06:54 AM
#12
Intermediate
I’m confused now. Maybe only the front strut are adjustable? The instructions for the front shows the top valve being adjustable when turning the valve different degrees for stiffness.
10-20-18, 07:12 AM
#13
Lexus Test Driver
Looks to me like they are pointless. And I now wonder if they even had a test car when R&D'ing these, and if they did, how they thought it was acceptable to negate a very important aspect of the air suspension as designed by Lexus.
10-20-18, 02:09 PM
#15
Intermediate
In our LS460, we have semi-active meaning we can switch from stiff to soft on the dampeners or leave it as normal. The actuators above the shock/strife turns clockwise or counter-clockwise to determine how stiff or soft the ride is.
Stiff means less vertical movement of the strut which puts more stress on the seals and hydraulics of the strute, soft means more travel (a lil more bouncy) and puts more stress on the air bags. People think the air bag controls the dampening effect of using the sport/comfort mode switch but they don’t.