Transmission problem
I have a 2005 Southwind with 32,000 miles on a Workhorse chassis/engine with an Allison tranny. While driving at about 35-40mph I felt a clunk noise in the transmission with a slight bucking sensation...
Forum Discussion
I will hazard a WAG and say plug wires are causing the bucking. When the engine bucks it is very possible for the trans to misinterpret the relationship between input and output speed / converter and tail shaft speeds, and set a light. The fact that the light went out indicates a temporary or intermittent problem that is no longer being seen by the control unit and possibly not recorded as a fault. Hopefully it will be plug wires and that you replace them with one of the good quality, ceramic coated boot, high temp wire kits available.
