AHC issue after bump, now leaking – mechanic says pump/reservoir

[savvy100]

Hey all,

Looking for a sanity check before I commit to a fairly expensive repair on my 2010 LX570.

A few days ago I got the “Check 4WHEEL AHC System” message. It actually triggered right after I hit a bump. Since then, the truck seems to be stuck in N (normal height), but honestly the ride still feels totally fine—no harshness or weird behavior.

Took it to a local mechanic I trust and here’s what he found:

• No obvious issues at normal height
• When the vehicle was raised, a hydraulic leak showed up
• He traced it to the AHC pump/reservoir assembly, specifically where the pump interfaces with the reservoir
• His recommendation is to replace the entire pump/reservoir unit

I’ve attached a couple photos of the area. You can see there’s fluid buildup around where the hard lines go into the unit and around the housing.

Before I pull the trigger on a ~$2k+ part, I wanted to get a second opinion from folks here who’ve dealt with AHC:

Questions:

1. Does this actually look like a pump/reservoir failure to you, or could it still be a fitting/line/seal issue?
2. Has anyone seen leaks that only show up when the system is under pressure (i.e., when raised)?
3. If it is the pump/reservoir, is replacing the whole unit the only real fix?
4. While I’m in there, would you replace accumulators proactively or leave them alone if ride quality is still good?

Truck is otherwise in great shape and I’ve been slowly bringing it back to baseline, so just trying to make the right call here instead of throwing parts at it.

Appreciate any insight—thanks in advance.