Extend the frame

I have modified my Six Pac and it weighs about 1000 lb. loaded. I have added Air bags to the rear suspension and have not had any problems in 15 years. My current truck is 3.0 V6. It can haul a grade and maintain 55 mph. My understanding is that the 3.4 and the 4.0 V6 have a much better power to weight factor. It should preform better than what I have now and get better mileage.

I haven't calculated what my camper design will weigh yet. I am hoping for around 1,000 - 1,200 lbs.

 

A frame splice is doable, similar to how AEV makes Jeep Wrangler pickup conversions:



However, the Tacoma frame is double-walled, riveted together, so you will need doublers inside and outside.

Longer driveshaft is relatively easy - just measure the distance between flanges and order a custom one-piece from http://www.4xshaft.com/ Then you will need to extend brake lines and wiring.

Other unknown but possible effects include VSC misbehaving due to the longer wheelbase.

 

With the camper on it is somewhere between 13 and 14 mpg.