I think it is the transmission (assuming it is auto)
When you stop the transmission is still in a higher gear. Right after you stopped the transmission shifts down to first gear, giving the jolt when it engage. I don't feel it much on my Tacoma (just slightly), but I have a Ford Explorer also that does it very pronounced and it is clear that it is the transmission. Just to check it, I have approached the stop slowly to make sure it completes the downshift before I stop, and then it does not happen.