Greetings Alain

I have experienced similar problems with coolant loss where it remains
normal for quite a period of time then drops over a few days. I
discovered numerous leaks around hoses with gear clamps. Mainly the
large coolant pipes running under the van. The largest leak I found to
be at the rear where the rubber hose joins the plastic pipe and
distribution unit. Turned out to be a cracked flange at end of plastic
pipe. During extended hwy driving I could lose 1" of coolant in the
refill tank. Do NOT over tighten gear clamps.
Cuurently I have found other little leaks:

Distribution unit developed a crack
Expansion tank cap leaking
Water Pump seal at head showing beads of coolant

Hope this helps.

R.Feuerriegel
88 syncro

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