Chrysler Repair: cruise control taking truck out of lock up but staying in cruise, abs light, lamp switch

Question
when cruise control is on my 03 ram 5.9 gas the torque convertor will sporadically disengage and re-engage with 100-200 rpms fluctuations. i am also a technician at a dealership i am not familiar with the trucks speed controls whatsoever. the problem appears to get worse when the cruise is on for awhile on a high with little to no throttle position changes. i recently had an abs lamp come on shortly after this problem occured, it was out the next time the truck was started. i have not heard this being a common problem with these trucks. it has a new cruise control actuator assembly yet the problem is persisting intermittently. has anyone heard of this before? given the systems and the abs light on it would almost lead me to believe that there is a problem with a brake pressure sensor or a brake lamp switch however you would think if the brake lamp switch was activating the cruise would shut down totally? i am scratching my head with this problem for a few months now any info would be helpful

Answer
Hi Lee,
That is unusual. My first suggestion would be to see if you can get any fault codes that might be stored in the powertrain/transmission/abs controllers. Let me know what you get by doing that. I will see if there is any aspect of the cruise control that would cause this.
Roland