PabloCruise
SILVER Star
Your LX was driven 4k miles in 6 years??? Or is that supposed to be 40k miles?
AHC Fluid Change How To -- Need Input (2 Viewers)
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Your LX was driven 4k miles in 6 years??? Or is that supposed to be 40k miles?
Previous owner just did not drive my 2002 LX470 much.
Only had 24,930 miles on it when I purchased it March of this year.
December 2010 was when the AHC was changed.
Its 4,000 miles in the last 6 years --- and 3,000 of those miles were in the last 4 months that I owned it.
PabloCruise
SILVER Star
You will likely enjoy that LX for many years...
For clarity to folks like me who are pretty new to the LX, is there a picture of the "bump stops" mentioned in the
procedure? Or is this going to be readily apparent when I get down under the vehicle?
procedure? Or is this going to be readily apparent when I get down under the vehicle?
PabloCruise
SILVER Star
Probably apparent. If I remember, I will get a picture next time I am under the LX
"bump stop" = general term for a buffer that prevents metal to metal contact between suspension and chasis when suspension is approaching full compression in this case. Not LX specific at all.
Just completed the 1 can fluid swap, pressures before were 7.6/6.9, after 7.9/7.0, 5 turns on TBs brought it down to 7.2/6.8. I plan to drive around some tomorrow and see how it settles in and possibly go 1 more crank.
New owner of an 11 LX w just over 60K, after reading on here to learn about the process to replace the AHC fluid in a 200, I've put it in L and am siphoning the reservoir old fluid first. I removed the cap, took out the screen just inside the fill port and inserted a small tube (actually MB diesel vacuum line tubing) down into the reservoir and it's draining very slowly. A larger siphoning tube would be faster. To refill it I used the funnel contraption shown below - the hose fits snugly into the fill port and stays put so one person can do it alone.
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It's definitely different. I got about one liter out of the reservoir then replaced that with a full can of new fluid, then let some out from each bleeder. The tank is larger than it appears from the service window. At 60K the old fluid wasn't too dirty, looked dark in the bottle but fairly clear coming out of the bleeders.
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I'm just wondering bought my car and fluid was on minimum and my mechanic topped it up to max.Do I need to bleed the system a there 5 points or 4 point? .I'm going to do the health test for the accumulators from l to h first so anything above 7 is good on level of gauge as ride is a bit little bouncy.
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uHu
Bridgeburner
It's always good to bleed a bit, at least to check the condition of the fluid at the actuators. There is no real circulation of fluid in the system, so the fluid can be nice and good in the reservoir, but black and useless at the bottom end.
If the level of fluid has gone down, it's either because of a leak, or because the accumulators have lost some of their pressure. So, if there is no leak, it is likely that you will see that you have less than 7 to 8 notches difference when going from Lo to Hi.
If the level of fluid has gone down, it's either because of a leak, or because the accumulators have lost some of their pressure. So, if there is no leak, it is likely that you will see that you have less than 7 to 8 notches difference when going from Lo to Hi.
aaronrules
Coolest person you know!
So I am planning on the sensor lift from this thread:
AHC Sensor Adjustment for Lift
I am wondering if I should to the fluid change before I do the lift? My thinking is that it will be easier to deal with stock height for the fluid change, and then just add whatever is needed after the sensor lift.
Thoughts?
AHC Sensor Adjustment for Lift
I am wondering if I should to the fluid change before I do the lift? My thinking is that it will be easier to deal with stock height for the fluid change, and then just add whatever is needed after the sensor lift.
Thoughts?
PabloCruise
SILVER Star
Sounds reasonable. If you haven't changed your fluid recently, you might as well...
PabloCruise
SILVER Star
Nothing to worry about. One can is sufficient for a good exchange and bleed, particularly if you're comfortable with working on hydraulic systems and can do it efficiently. For a lot of guys here though this is all new to them and in that case it's better to have more fluid (2 cans) on hand than being left short in the middle of the process; or if it's a first time ever fluid change then you'll benefit from a follow up bleeding to establish a good baseline. The trick is to not drain more than you can replaceAn opened second can be resealed pretty well and stored for later use.
Edited to include:
Here's my version of a quick and easy 1 can AHC fluid exchange/bleed. Following this process is less likely to get you into trouble by reducing the risk of accidentally bleeding too much fluid thereby allowing air to be drawn into your system.
Materials required. One can of fluid (Toyota suspension fluid, AHC 08886-01805), clear pvc pipe that's a snug fit on the bleeders, 10mm spanner/box wrench/crows foot and a suitable waste fluid container.
This process assumes the fluid level in the reservoir is between max and min at N height before starting. Clean around the reservoir cap and the spout of the AHC fluid can before opening.
1. Lower the vehicle to L and wait 30 seconds for the AHC system to settle and then turn the vehicle off, do not restart until step 8. The fluid level in the reservoir will now be at its highest. Using a turkey baster or similar remove as much fluid as practical from the reservoir. This amount should equal, or be slightly over, 1 liter.
2. Pour the entire 2.5 liters of new fluid into the reservoir, filling it.
3. Now we know that the reservoir's "normal" contents is ~ 1 liter (vehicle in L when fluid level is correct at N) and we have filled it with 2.5 liters so we don't want to drain more than 1.5 liters or else we may come up short.
4. Starting at the height accumulator (12 in long cylinder on DS outer frame rail, between front and rear damper assemblies) drain fluid, closing the bleeder as fluid flow stops which should be ~0.3 liters.
5. Move to the front LH damper and drain until the front is on the bump stops. Both sides will lower and you should drain ~0.4 liters. Again close the bleeder as fluid flow stops.
6. Move to the rear LH damper and drain until the rear is close to/on the bump stops. Both sides will lower and you should drain ~0.3 liters. Again close the bleeder as fluid flow stops.
7. Now we should have drained very close to 1 liter (0.3+0.4+0.3) leaving us about 0.5 liters additional in the reservoir.
8. Start the vehicle and raise to N. The system will refill and recharge with new fluid from the reservoir. The fluid level in the reservoir will lower to slightly over the max line if everything has gone as expected.
9. Turn the vehicle off and do a small, quick bleed on the PS front and rear dampers just to check that there isn't any gas trapped. You don't need to remove very much at all from the PS as essentially all available fluid (there will always be a small residual in each shock actuator that we can't access) gets pushed out when you do the DS and take it to the bump stops as both sides are hydraulically connected.
10. You're done, confirm that the reservoir fluid level is correct - between max and min at N height with the engine running. There is nothing wrong with leaving the level slightly over the max line.
As long as you don't drain more than 1.5 liters you can't mess up and accidentally draw air into the pump/system.
This approach is simpler than others, but slightly more elaborate than the FSM. It is intended to remove as much old fluid as practical in a quick and efficient manner. Hopefully it fills an information gap by associating approximate quantities to the height accumulator and front/rear hydraulic circuits. Hopefully this guidance falls between the very brief FSM directions and other available AHC bleeding procedures that may appear complex and daunting to some.
Nothing to worry about. One can is sufficient for a good exchange and bleed, particularly if you're comfortable with working on hydraulic systems and can do it efficiently. For a lot of guys here though this is all new to them and in that case it's better to have more fluid (2 cans) on hand than being left short in the middle of the process; or if it's a first time ever fluid change then you'll benefit from a follow up bleeding to establish a good baseline. The trick is to not drain more than you can replace
Edited to include:
Here's my version of a quick and easy 1 can AHC fluid exchange/bleed. Following this process is less likely to get you into trouble by reducing the risk of accidentally bleeding too much fluid thereby allowing air to be drawn into your system.
Materials required. One can of fluid (Toyota suspension fluid, AHC 08886-01805), clear pvc pipe that's a snug fit on the bleeders, 10mm spanner/box wrench/crows foot and a suitable waste fluid container.
This process assumes the fluid level in the reservoir is between max and min at N height before starting. Clean around the reservoir cap and the spout of the AHC fluid can before opening.
1. Lower the vehicle to L and wait 30 seconds for the AHC system to settle and then turn the vehicle off, do not restart until step 8. The fluid level in the reservoir will now be at its highest. Using a turkey baster or similar remove as much fluid as practical from the reservoir. This amount should equal, or be slightly over, 1 liter.
2. Pour the entire 2.5 liters of new fluid into the reservoir, filling it.
3. Now we know that the reservoir's "normal" contents is ~ 1 liter (vehicle in L when fluid level is correct at N) and we have filled it with 2.5 liters so we don't want to drain more than 1.5 liters or else we may come up short.
4. Starting at the height accumulator (12 in long cylinder on DS outer frame rail, between front and rear damper assemblies) drain fluid, closing the bleeder as fluid flow stops which should be ~0.3 liters.
5. Move to the front LH damper and drain until the front is on the bump stops. Both sides will lower and you should drain ~0.4 liters. Again close the bleeder as fluid flow stops.
6. Move to the rear LH damper and drain until the rear is close to/on the bump stops. Both sides will lower and you should drain ~0.3 liters. Again close the bleeder as fluid flow stops.
7. Now we should have drained very close to 1 liter (0.3+0.4+0.3) leaving us about 0.5 liters additional in the reservoir.
8. Start the vehicle and raise to N. The system will refill and recharge with new fluid from the reservoir. The fluid level in the reservoir will lower to slightly over the max line if everything has gone as expected.
9. Turn the vehicle off and do a small, quick bleed on the PS front and rear dampers just to check that there isn't any gas trapped. You don't need to remove very much at all from the PS as essentially all available fluid (there will always be a small residual in each shock actuator that we can't access) gets pushed out when you do the DS and take it to the bump stops as both sides are hydraulically connected.
10. You're done, confirm that the reservoir fluid level is correct - between max and min at N height with the engine running. There is nothing wrong with leaving the level slightly over the max line.
As long as you don't drain more than 1.5 liters you can't mess up and accidentally draw air into the pump/system.
This approach is simpler than others, but slightly more elaborate than the FSM. It is intended to remove as much old fluid as practical in a quick and efficient manner. Hopefully it fills an information gap by associating approximate quantities to the height accumulator and front/rear hydraulic circuits. Hopefully this guidance falls between the very brief FSM directions and other available AHC bleeding procedures that may appear complex and daunting to some.
Thanks @PADDO - that was incredibly easy!
@PADDO appreciate your write up. This was really easy to do.
At 136k the bleeders had never been opened. They were relatively easy to work with since it was a NorCal truck.
After draining close to 1L from the reservoir I got close to 1.5L even though fluid only came out of the DS globes / accumulator.
The wife claims nothing's different about the ride - I disagree it feels smoother.
Since I don't have a TIS will have to wait on torqueing the torsion bars and replacing the rear springs... which, need to be done because when fully loaded with 7 healthy Texans the rear will sometimes drop to L yet somehow recovers if I start in H?
Overall I have to say I love the AHC ride - for my DD purpose it's a fun change from my old B8's Bilstein/HR setup...
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I replaced the four accumulators a couple of months ago with OEM. Last weekend I decided to "flush" the fluid one more time. This time, barely any fluid came out of the front driver side accumulator. The rest of the accumulators flowed fine. So I decided to do another flush today to see if more fluid would come out of that front driver side. Same thing, barely any fluid. Maybe an ounce or two. Should I be concerned? Any ideas? Thanks.
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Just did mine today on a new to me 05 LX. PB blaster on the zerks and no issues although all maintenance intervals had been completed at the dealership by the PO. PDF was a great help- Thanks! I used a 2.5l can plus an eighth or so of the next one to get it to the max line after a couple cycles. Now for the bearing repack to complete the 120K and swapping diff and t-case fluids for extra credit.
Question: my new to me LX570 had a single AHC replaced at the dealer about 2k mi before I bought it (at 99,000 mi). Would the dealer have flushed the system/changed the fluid at that point? The vehicle had had it's 100K mi service completed.
All previous service had been done on time at the dealer. Is AHC service part of routine maintenance at some mileage point and would have already been done?
Thanks!
AA
All previous service had been done on time at the dealer. Is AHC service part of routine maintenance at some mileage point and would have already been done?
Thanks!
AA
I believe you can go on the Lexus website, sign-up / sign-in, and find out exactly what has been done.
