Strange bump feeling on starts and stops

Hello Guys, I'm new to this forum. The name is from my grandson cause I raise cows and he said I say Mmmm to the cows. Lol
Anyway, I just bought a 2010 Tacoma and the dealership had just replaced the leaf springs. I got the same driveline bump on starts and stops. I checked out the shackle bolts and they needed tightening. I thought it was axle wrap too. However it didn't get any better. There is considerable movement in the springs when the truck is moving from forward to reverse. I don't know if that is what I am feeling or not, because it can happen when the truck is sitting completely still. I took it to the dealer and they said everything in the springs and that movement was normal. They said it could be something internally in the driveshaft. I never heard of a driveshaft having internal parts. Then I look up all these posts. The Tundra has the same thing. One thread said it was the transmission shifting down to first since that is such a low gear that the transmission can't skip shift from 4th or 3rd to 1st. It drops in later. Don't know, sounds crazy to me. I wonder if I should try to pull a load with this truck or not. What do you guys do with a load like a trailer? Any problems?

 

Mine has always done it. Random.
clunk stopped at a light. I believe it is the transmission or the torque converter switching somehow. I have even had my foot lightly on the brake and felt a slight surge foward after the noise which confirmed for me anyway it was something shifting in the drive train.

 

Thanks RKTaco,
Any problem towing a load?

 

I have this exact same problem, have you found any remedies?