One problem related to spare tire has been reported for the 1999 Toyota Sienna. The most recently reported issues are listed below.
Loose spare tire in cargo seating area of Toyota Sienna 1999 van. Due to a recall on the corrosion of the spare tire cable, the spare tire was removed and placed in the cargo area of the van. The tire is not secured down and moves around during driving. If there was any type of accident, especially a roll over, the tire with the rim would be able to move around the seating area and could cause severe injuries. I do not feel safe driving this vehicle. I did call Toyota with my concern with the tire not being secured, they gave me a case number and told me that there was nothing they could do at this time.