05 Tundra Replacement speakers?

[rondel]

I keep hearing that the tundras have an amp other than the one in the factory radio. I have a 2005 tundra access cab and I have looked under the rear seat and don't see an amp. Is it all the 2005 tundras or just some that have an amp. I am changing to factory speaker with infinity 6022. I went with these due to they don't need a lot of watts and the low freq. is in the low 50's. Not a subwoofer, but for 6 1/2 inch speaker I think it is not bad. What is ya'll opionion on this.
Thanks Ron

[Big_Al1]

Mine didn't have an external amp I think its just the ones with the jbl system that do.