Goku can go up to Super Saiyan 4 there is no DB AF.
yes he can transfom into 3 levels of super saiyan but the forth is a seperate character
Goku SSJ4 is the most powerful super saiyan form that Goku can transform into
No super saiyan 4 is the max Goku can transform too.
Gohan is stronger if goku is in his normal form but if they are both in super saiyan 2 form or if Goku is in super saiyan form then goku is stronger.
4
Actually, yeah he was. He could have gone way beyond the levels of that of a super saiyan easily. But he wanted Gohan to do it before him. That's why he didn't transform into a super saiyan 2. If he did, he would have crushed cell by himself. There are proof as well. After Goku died, he fought Pikkon and became a super saiyan 2 even without practicing. It's because he knew how to.
In the fictional TV series Dragon Ball, and all its successors, it is possible for a normal human to become a Super Saiyan by use of a Dragon Ball wish. Otherwise, according to Goku, a Saiyan unlocks the Super Saiyan transformation in a time of great need. However, Vegeta became a Super Saiyan just by desperately wanting to surpass Goku.
When he was in the Hyperbolic Time Chamber training to beat Cell. I think he became Super Saiyan 2 after he died to save the world from Cell. If Goku could turn Super Saiyan 2 he would have beaten Cell himself, instead of making ohan fight him.
Gogeta, the fusion of super saiyan 4 Goku and Vegeta.
Super Saiyan 2 goku cause he was able to defeat Broly as a Super Saiyan 1
Goku does not turn super saiyan 6 or 5 in fact. and it only goes up to super saiyan 3 in the manga and super saiyan 4 in the cartoon.
Well, it depends on the specific show of the series Z: The furthest anyone reached, saiyan wise, is Super Saiyan 3. Found out by Goku. GT: The furthest anyone ever transformed was Super Saiyan 4. Also founded by Goku. Super: Arguable, but, God Of Destruction Vegeta or Mastered Ultra Instinct Goku. {Can be argued, but the newest transformation really is G.O.D Vegeta}