maybe/maybe not?So it's safe to say then if living out of a vehicle setup that will be very close to or over max GVWR and GCWR that anything with the Toyota 4.7 V8 is a bad choice.
I've owned a bunch of 4.7's. Towed 6500# with them fairly regularly. I personally never had a problem with the manifolds. I also was fortunate to never have a problem with losing 4th gear in the trans, which was common in the 4-speeds. Shoot, I never even had rusty frame issues... IMHO, one of their more solid engines.
But that's just 5 4.7's out of millions, so it's definitely not a scientific poling.