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This hose connects the coolant pipe to the radiator of the T3 Vanagon. It is the lower hose, part of the return line. Please note that the hoses of the early Vanagons (82-85) have a smaller diameter compared with the later ones (86-91).
There is also another edition for later T3 Vanagons with larger tire diameters.
Part Numbers: 251121083G, 251121083H, 255121081A