general problems of the 2021 Ford E-450

Component= traction control and cruise control. Safety risk=driving a Ford E-450 class c RV on interstate at 63 mph going generally up hill with cruise control on, the "service advancetrac" warning light came on dashboard. I immediately lost cruise control capability and steering became a little shakey. Pulled into rest area shut vehicle off. A few minutes and started again. Error went away and cruise control was functioning. Happened again a few hours later and I did the same thing and continued on. What happened=as I was driving, the " service advance traction" light came on and the cruise control stopped, my class c RV immediately slowed at a high rate, a semi was behind me trying to get over to the middle lane. When I slowed down suddenly due to the cruise control going out, the semi had no choice but to change lanes quickly missing the back of my vehicle by a foot or so. If he was not alert as to what was happening, I most assuredly would not be typing this letter. It was that close!! note= this also happened last year as we only take the RV out a few weeks out of the year. I brought it to klammer Ford in new port richey f1l immediately after we got back from the last trip. They could not reproduce issue or find anything wrong lamps= the only warning light that came on was a "service advance traction" light. No prior indication of any kind.

The service advance trac light comes on sporadically. This also triggers the cruise control and hill start assist to turn off. Any of these malfunctions could prove to be a safety issue particularly with regard to stability and control of the vehicle. The vehicle has not yet been to a dealer for these issues as we are traveling. The malfunction has occurred about 5-6 times while driving, without any particular triggers. There were no early warnings and the first time the service light came on was June 18th and we were on a two lane flat road doing about 50 mph. The advance trac (and cruise/hill start) remains non-functional until vehicle is turned off for at least 10 minutes. It then often resets and performs normally until the next failure - which does not seem to be predictable.