Adam Clarke on 1 Samuel 13:5

Thirty thousand chariots, and six thousand horsemen - There is no proportion here between the chariots and the cavalry. The largest armies ever brought into the field, even by mighty emperors, never were furnished with thirty thousand chariots.

I think שלשים sheloshim, Thirty, is a false reading for שלש shalosh, Three. The Syriac has telotho alpin, and the Arabic thalathato alf, both signifying Three thousand; and this was a fair proportion to the horsemen. This is most likely to be the true reading.