2015 Prostar has stability and handling issues when hooked to a trailer

Bought truck in January and have put new shocks, tires, front end suspension, and 3 axle alignment. Now the truck has that unstable feel and when a truck passes it feels like I’m being pushed to the right and hydroplaning feel of poor handling. Feels like truck will roll over when in curves or angled roads. It also feels like brakes are being applied slightly when this happens.
No dash codes will appear. The only thing that’s on is ABS module in the mileage box area when I start the truck. 9-10 different shops and if there is no code on read out, they just say “there is nothing wrong “. So frustrated with it all.

 

5th centered and the issue was steering angle sensor. Recalibrated it and was doing fine until I was on pitted roads , then went out again. At the 17th International shop since mid March and over $20K later, they agree that sensor is bad. Yaws checked good and can’t find any wires that could be shorting out causing this issue. I have had the sensor calibrated 8 times since May 13th. Will keep you updated on results. To many sensors controlling the truck instead of me.

 

More grease then there would on two 5th wheels. I hate seeing dried up 5th wheels.
Didn’t put steering angle sensor in as the shop foreman said it has to be Bendix radar on front. They said it was not registered in the ECM? Recalibrated the YAW and angle sensor. Just picked up first load and heading toward home. A little test run.
When driving in slanted roads (either way)!truck feels in stable as if it going to “roll”. This occurs even on rutted roads I can’t make lane changes it’s a fight against the Terminator. As long as I keep Truck “leveled” it will be okay. It doesn’t matter what speed I’m traveling. HeavyD I have been reading all your post back. I have tried everything at least once. I need to break down and test body controller. Just not sure on testing wires and exactly what I’m looking for Just want to say thank you HeavyD

 

Ok will do that when I get back to truck in morning.
Is there a chance that I have a bad sensor or short in wiring? There are no fault codes and only check engine light with no code to go with it. The light goes off. Newest symptom now after “syncing “ Bendix wingman to ECU, now when I’m driving it’s like the engine/truck is trying to decelerate and I’m forced to push harder on pedal. Then it feels like it releases for a short time and does it again. (Cummins isx 15) also, hard to shift transmission like it’s not syncing with clutch/speed. If that makes any sense to you. I’m ready to tackle this issue with your help. Fed up with techs that can’t think outside that darn laptop. I really appreciate your help.