By the way, where is the egr valve located?? Maybe I can do it myself.

 

The EGR is easy to get to. It is right in front of the motor on the passenger side. Kinda under the air intake tube. It's dark outside here so I can't look right now, but generally that's where it is. Very easy to replace. It took me about 15 minutes. It would have been faster except the damn thing was still so hot from driving. I bought it at the dealer for about $50.
My tuck was also bucking and feeling like it was holding back, but only at low speeds like 30 or 40 mph. On the freeway it always ran smooth. The dealer had no clue what was wrong and told me it wasn't doing it while they did the test drive and there were no codes for them to troubleshoot. It was up to me to find the problem and I was going to keep replacing things until I found the problem.