Is there any true lifetime warranties?

Hey guys, I'm looking for some advice on buying a new truck. I'm looking a new diesel F250, but I've been burned before. Is there anyone offering lifetime powertrain warranties without a bunch of red tape? I've had to replace the motor in previous trucks, both of which were $20k+ and I don't want to do that again. Here's some details:

• I drive 80k to 110k miles a year, with a travel trailer. My wife and I are retired and travel all across the country.
• Have to have diesel because towing through the mountains with a gas truck was terrible.
• Based out of Texas.

Most of the Ford dealerships ive talked to that offer a lifetime powertrain warranty have a coverage cap of $4k or force you to do maintenance at the dealership you purchased it from, which isn't possible for us. Thanks for the help!