engine break problem

they assigned me with a automatic peterbilt 579. im used to the frieghtliners, the engine break is completely different from what im used to. im on i-70 in colorado and last night, i notice there was lot of smoke comin from the tandems. my question is, how do i use the engine break for the peterbilt 579 automatic, i thought i was doin sumthin good when i was using the engine break but i was wrong, plus i was going extremely slow and smoke was still coming from the tires. what is the problem here?
EDIT: i was doing sumthin wrong the whole time, i wasnt using the engine break i was using sumthin else the whole time. thats why there was smoke, i just look at the online driver manual. i hope nuthin is damaged

 

i dont think it has any, any tips on how to use it?

 

engine was engaged, i felt the stoppin power. i do not know if i was over using it causin the brakes to overheat creatin the smoke. i normally use both engine break and lightly tappin on the brake to avoid the same problem im havin right now. but for some reason smoke was still comin from the tandems and i wasnt goin fast at all. i was below 40 mph, im around 76k pounds btw but in the frieghtliners tht i was drivin. i had no problem even at tht weight cap

 

the brakes are adjusted properly, "You would have to apply the brakes for the tandems to smoke" are u sayin i shouldnt apply the brake, just use the engine break instead?

 

i was doing sumthin wrong the whole time, i wasnt using the engine break i was using sumthin else the whole time. thats why there was smoke, i just look at the online driver manual. i hope nuthin is damaged