NHTSA Complaint #11594828 — 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.