So this comes up a lot, people think that the 4Runner and Tacoma are related - I’m here to set the record straight: The Tacoma and 4Runner are not and never have been the same truck.
Yes they share components, but they are different chassis entirely and a 4runner is NOT a Tacoma SUV.
Before you freak out its important to note that there is a difference between a Toyota Tacoma and a Toyota “Truck”
Back in the day the Toyota Truck, known globally as the Hilux but in north america as “Truck” was the truck Toyota had been importing to people to use as a working vehicle. In the mid 1980's it was used as the base of a new kind of “crossover” vehicle between a family vehicle and a truck, the 4Runner was born and it was, for all intents and purposes, a Hilux SUV. In fact, in some markets it was simply called the Hilux Surf
Same truck underneath, but the bed was now part of the body shell, which body was reinforced with internal bracing for when you took the fiberglass back off. In fact, before Toyota had a go at the SUV full swing they tip toed into the market with the Trekker, a factory authorized conversion of a Pickup into an SUV by Winnebago (you can read about it here if you want)
The point is that, yes, the Hilux and the 4runner were the same truck, for the 1st generation of 4runner, and the 2nd.
In 1995, as Toyota grew larger and gained a strong US presence the need to build a pickup truck domestically to get around the 25% import tariff on small trucks as well as to strengthen its brand in North American meant it was time to leave the work based Hilux to other markets and create the North American styled, built and recreationally focused Tacoma to replace the rough and tough Hilux.
The Tacoma was no longer related to the Toyota Hilux, which continued to be sold elsewhere in the world which meant that the by now very popular 4Runner, would need to come from somewhere else. Strong growth in the SUV market as a suitable family vehicle meant that a truck based utility vehicle no longer made sense as a base and so Toyota looked elsewhere for a suitable platform and found one in the international light duty Land Cruiser known as the Prado (Code J90) on which the 3rd gen 4Runner was based
While many components continued to be shared across the entire light duty truck range (engines, transfer cases, transmission, axles, some front suspension components) they were different platform: Tacoma, Hilux and Prado/4runner.
It’s here the pickup trucks and SUV’s in North America diverged and never again crossed paths. The Tacoma continuing on as a stand alone model made in the US and Mexico, and the International Prado/4Runner made in Japan which made financial sense to Toyota since only trucks (and not passenger vehicles like SUV’s) were subject to the import tariff. Hence, a Tacoma and a 4runner have never been [directly] related.
The 4th generation 4Runner moved to the new J120 platform which was followed up by the Fj cruiser which was also based on the J120. In addition, the 4th generation J120 Chassis also brought us the Lexus Gx470, which is most visually similar to its platform donor, the Prado J120
The Current GX and Prado J150 are again virtual doppelgangers based on the latest platform of Prado
As well as the current 5th Generation 4runner
Once again, there are many mechanical similarities to the Toyota light duty trucks (Hilux, Prado/4Runner/Tacoma) but they are not the same platform.
Interestingly enough, in markets where the Hilux is still sold there IS an suv based off that platform called the Toyota Fortuner. It exists separately from the Prado and is, ironically, built to satisfy the more pedestrian roles the 4Runner was meant to take on when it adopted the Prado chassis, which in other markets is seen as a much more agricultural and traditional SUV.