Hard pull to right upon deceleration

What is your question?

when I lift off the accelerator the van pulls hard to the right. If I accelerate during the pull to right the van corrects back to straight. During braking there's no pull. Hard acceleration is straight and true. Only when lifting off the accelerator does it dive to the right. When cruising along there is also a pull to the right and a wobble feeling at about 40mph but stops above 40. Thanks