With the automatic you should probably have the 4.30 gears so going to 32 or 33" tires shouldn't hurt too much. I think it hurts the 5 speed more because they usually have 4.10 gears. I've run 3 different 86-88 4Runners with the automatic and 32" tires and never had any problems. On my 86 I ended up getting the Downey header and it helped make up for the perceived power loss.