I have this so far...
=VLOOKUP($B$1,'Trailer Summary '!$A$4:$K$17,MATCH('53902'!A$3,'Trailer Summary '!$A$3:$K$3,0),FALSE)
however 2 things...
1. you have headings in sheet2 that dont appear in sheet1. i designed the formula to use the column headings to bring back the data so you dont have to mess around with "how many columns"
2. if you are going to have more than trailer # on sheet1, what would distinguish them apart? could 1 of the load dates be used to make them "unique"? (ie combining the trailer # and a date to create a unique ID)