I have just bought a new travel trailer that weighs 4800lbs. I have a 2007 Tahoe with 100,000 that is like brand new. I don't want to trade it but I have found that the 5.3 engine has a tough time on hills and it only gets about ten miles mpg. My question is can a 6.0 engine be put in it successfully and has anyone here had any experience with doing this? Thanks in advance for your help.