When I do a burnout it's always my left tire that spins but I noticed that sometines it switches is this normal for a truck without posi Does it need maintaince?

 

Welcome to the forum...
what year of truck? most likely you have a limited slip differential...
The limited slip feature is what is most likely causing the wheels to "switch" as to which one is spinning... you can wear out those clutches....

 

If it's the 04 like in your name, it's a g80 limited slip. I wouldn't do to many burnouts with that in the rear. Those go out all the time, even unexpectedly so beatin on it probably isn't a good thing