Rashi on chumash is based on chazal. Sometimes Rashi appears to bring contradictory opinions and some mefarshim say that its machlokes midrashim.
Is there a source or mesorah that Rashi's shita in chumash shtims with all Rashis? That Rashi wont bring down two opinions that contradict each other (I'm not asking when he brings down 2 pshatim on one pasuk, which obviusly disagree with each other. Rather when he gives one explanation by one pasuk, that it wouldn't contradict himself elsewhere)?
(Im asking specifically on chumash, because it is a more unique peirush than shas. As said by rabeinu tam. Also he fasted 613 fasts before writing it...)