Is it normal for a toddler to sometimes repeat last syllable of a word? for example truck-k-k or feet-t-t. he only does it once in a while.

Absolutely: Its very normal. You can help him by being encouraging and patient with him. Let him take his time finishing a sentence.

Non-fluency is seen: In typically-developing tots age 2-5. Stuttering that starts < 3 usually is outgrown in ~ 6 mos. Have a speech/language therapist test him if it lasts > 6 months. Don't pressure him to stop repeating phonemes,the smallest units of sound in a language, or rush him. You can gently repeat what he says without the stutter, as in, " You'd like to play with the truck?" Read, talk & play.