Question about WGS84 Datum 2004 Upgrade in GPS technology and devices Posted August 9, 2011 I would guess that it's a plus /minus (east/west)problem with the longitude...... Any changes to WGS84 would be of the order of centimeters. It's not going to fix your problem. Now Fizzy, you know better than that ! If written coordinates are input (into software or into unit) but the direction of longitude is incorrect, the error can be exactly as described. Were you thinking about the difference between NAD83 and WGS84?