LX570 AHC “Basics” - Added as sticky thread for AHC Issues (3 Viewers)

[04UZJ100]

Haha, Alaska problems. Our only real Toyota dealer is attached to the Lexus dealer the others are owned by the same group and extremely small and pretty far away.

Don’t be turned off by doing the trans fluid yourself. It’s stupid easy. Disconnect inlet to the front transmission radiator, start truck and pump out 2-3 quarts. Shut off, refill same amount through fill port, rinse and repeat.

Everyone is so turned off by the “level check” but all you need to do is put a little extra in each time. Once you’ve done the above until all 14ish quarts are out, simply idle the truck in park. Use an infrared gun to take the transmission pan temperature. Once at around 100F, pull the overflow plug (while car still running) and let residual dribble out. Done.

Took about 5 hours doing in meticulously on my 4Runner. Same procedure for LX. Can’t remember the exact temperature range but I believe it’s 96-115F. The only issue with the whole procedure is crawling underneath to pump fluid in the fill hole each time.....

 

[abuck99]

Trust your instinct towards the dealer. I concur with @04UZJ100 - take on the job your self if you have the time and place to work on it. As for the AHC service, I would bet that even the dealer simply drains the tank and prob would not bleed the system from both sides either. For that money you may save yourself the $$$ and just diy.

I've inspected a several of LX's over the past month that had documented 60k service: as one example of ignored check list items, not one of them had the drive shafts lubed or the U-joints lubed (all dry), no evidence of a wrench ever being on the driveshaft flange bolts either (they are supposed to re-torque at 30k & 60k). Point being, lots corners get cut for "dealer" services you expect to be performed.

 

[coleAK]

Thanks, I’ll have it on the lift to do the diffs. I was hesitant on the tranny since I’ve always heard it does a better job if you use an exchanger.

 

[mcgaskins]

Don’t be turned off by doing the trans fluid yourself. It’s stupid easy. Disconnect inlet to the front transmission radiator, start truck and pump out 2-3 quarts. Shut off, refill same amount through fill port, rinse and repeat.

Everyone is so turned off by the “level check” but all you need to do is put a little extra in each time. Once you’ve done the above until all 14ish quarts are out, simply idle the truck in park. Use an infrared gun to take the transmission pan temperature. Once at around 100F, pull the overflow plug (while car still running) and let residual dribble out. Done.

Took about 5 hours doing in meticulously on my 4Runner. Same procedure for LX. Can’t remember the exact temperature range but I believe it’s 96-115F. The only issue with the whole procedure is crawling underneath to pump fluid in the fill hole each time.....

Maybe it's just me, but that sounds like a total PITA After changing my diff fluid recently, I remembered how much I hate swapping fluids. I guess I'm spoiled living in Denver, but the local Toyota dealership does a great job and loves to work on the 200. They know what they're doing and charge fair prices, and there are tons of indy shops like Slee that are top notch too.

 

[bwell]

Using this very thread I just preformed the 60k maintenance on my 2008, flushed 5l of fresh fluid into the system. It's really easy. Rides great, actually just completed a 1500 mile trip over 5 days and couldn't be happier with the truck. Here's what my fluid looked like.

 

[coleAK]

So the AHC fluid is $40 per Liter at the dealer. For those that have done the flush how much did you use? I was going to get 3L or 4L

 

[04UZJ100]

So what is the consensus on service interval for AHC? Is 60k service sufficient?

Just picked up a 2014 with 75k and am going to have the AHC service done in the next few weeks. The system functions perfectly but I want to get it done. Is going over by 15k a bad thing? PO did not tow and I could tell truck was used lightly.

Anything specific I can look out for to verify the dealer actually flushes from each corner?

 

[coleAK]

I do mine every 30k since I tow and do a lot of off road. When I did mine at 30k the “new” was red and the “old” looked like old black motor oil. Others on this thread have said the same. I don’t have any evidence behind it but would guess that not changing it would cause more pre mature failure than much of a noticeable difference in day to day function. I’m about to do mine again at 60k last time it took me 1-1.5 hrs and was easier than bleeding breaks.

 

[Noah Miller]

I wonder what makes it blacken and break down. Moly in the assembly going into solution? Oxygen or water absorption? Heat? It's essentially hydraulic fluid under pressure, so just curious.

 

[coleAK]

My theory was dirt working it’s way in through the seals. Here in Alaska we have the super fine glacial dust everywhere (even in my house). I avoid driving through glacial plains at all cost. The guys I know that do in their off road rigs change fluids yearly and rebuild diffs regularly.

 

[FinallyGotOne!]

I did my AHC fluid at 57K and did not get black fluid, though it was discolored, like old brake fluid.

I bought five liters at ~$14 each from the Toyota dealer and I used just under four liters.

As far as I am concerned, getting the right pump for the new fluid and ensuring access to the reservoir was the trick to making this a simple job. I bought a little $20 pump https://www.amazon.com/gp/product/B01N5MRR8F/ref=oh_aui_detailpage_o09_s00?ie=UTF8&psc=1
and pulled the tire off to ensure ease of access. I also pulled off the filler hose and filled the reservoir direct and put an LED shop ight behind the reservoir so I could see the fluid level.

Easy! WAY less of a PITA than was swapping diff and TC fluids.

 

[04UZJ100]

I did my AHC fluid at 57K and did not get black fluid, though it was discolored, like old brake fluid.

I bought five liters at ~$14 each from the Toyota dealer and I used just under four liters.

As far as I am concerned, getting the right pump for the new fluid and ensuring access to the reservoir was the trick to making this a simple job. I bought a little $20 pump https://www.amazon.com/gp/product/B01N5MRR8F/ref=oh_aui_detailpage_o09_s00?ie=UTF8&psc=1
and pulled the tire off to ensure ease of access. I also pulled off the filler hose and filled the reservoir direct and put an LED shop ight behind the reservoir so I could see the fluid level.

Easy! WAY less of a PITA than was swapping diff and TC fluids.

Do you have a procedure you can share or that you referenced?

 

[04UZJ100]

I do mine every 30k since I tow and do a lot of off road. When I did mine at 30k the “new” was red and the “old” looked like old black motor oil. Others on this thread have said the same. I don’t have any evidence behind it but would guess that not changing it would cause more pre mature failure than much of a noticeable difference in day to day function. I’m about to do mine again at 60k last time it took me 1-1.5 hrs and was easier than bleeding breaks.

How did you go about doing it? If it’s that easy, I may just avoid Kendall and do it myself!

 

[coleAK]

I followed the process that PADDO layed down for the 100s. It is referenced earlier on this thread. Also with yours since the AHC wasn’t done at 60k, Were the diffs, AT and breaks done? They are also due at 60k in addition to oil.

 

[coleAK]

Also I use a drive on lift so that makes it easier.

 

[04UZJ100]

I followed the process that PADDO layed down for the 100s. It is referenced earlier on this thread. Also with yours since the AHC wasn’t done at 60k, Were the diffs, AT and breaks done? They are also due at 60k in addition to oil.

Diffs were just done as well as all new brakes front and rear.

AT I do myself at 90k. Have had no issues going that interval on my 100 or 4Runner with WS fluid.

 

[FinallyGotOne!]

Do you have a procedure you can share or that you referenced?

EDIT: Vacuum almost all of the old fluid out of the reservoir and replace with new before bleeding.

I used the bleed procedure; however, at each corner and with truck off I bled the body down until it stopped, tightened the bleed screw, ensured there was plenty of fluid in the reservoir, turned the truck on, gave the AHC time to get everything back up to Normal, and repeated until I saw fresh fluid bleeding out. Then I stopped and moved to the next corner.

Additional note: I was surprised to actually see air bubbles bleeding out with old fluid. Didn't expect that.

 

[MattyO]

I did mine today at 110k. Vehicle is new to me and I could not find record of it being done before. It definitely needed it. I ended up replacing 3 quarts total. I followed the same procedure as I have done for my 100 series. Put vehicle in Low, emptied and filled the resevoir, then started bleeding from furthest point. Not sure what I did wrong but in startup I got a check AHC message and after few minutes of engine running the reservoir was not going down and the AHC would not cycle. After a few more start ups and vehicle running it finally started working and the error message cleared.

 

[04UZJ100]

EDIT: Vacuum almost all of the old fluid out of the reservoir and replace with new before bleeding.

I used the bleed procedure; however, at each corner and with truck off I bled the body down until it stopped, tightened the bleed screw, ensured there was plenty of fluid in the reservoir, turned the truck on, gave the AHC time to get everything back up to Normal, and repeated until I saw fresh fluid bleeding out. Then I stopped and moved to the next corner.

Additional note: I was surprised to actually see air bubbles bleeding out with old fluid. Didn't expect that.

Are you able to vacuum the old fluid out after removing the cap with the wings? Or do you have to remove the filter assembly too?

What size tubing fit on your vacuum pump?

 

[coleAK]

Are you able to vacuum the old fluid out after removing the cap with the wings? Or do you have to remove the filter assembly too?

What size tubing fit on your vacuum pump?

No there is a screen under that white cap. I removed the black hose at the hose clamp pointed to with the arrow (yes field point, it was near by) and vacuumed and filled from there. Each time I filled I just slipped the hose back on over the nipple before I started the car to let it re level without re setting the hose clamp. Then slid it back off to add more fluid as needed.

The tubing from my break evacuator is similar in diameter to aquarium tubing.