Thinking about doing a diesel swap into my 96 tacoma ex cab, currently has the 3.4 v6 paired with an automatic its 4wd as well.
Did some searching and saw that it would be cheap and slightly easier to put an Isuzu 3.9L into it over the 4bt Cummins (3.9L)

 

Toyota offers a diesel that guys swap in as well. Much more plug and play and toyota reliability. Just got to get it from an importer as it was only sold overseas.

 

Could you shoot me some URLs??

 

http://lmgtfy.com/?q=toyota+4runner+diesel+engine

If you read the wiki it has the engine code for the diesel.

The ikz-te is what you want to look at. There are other options as well and even shops that you can send your truck to have the conversion done for you.

Google should turn up all sorts of info on options.

 

there was also a thread here about it. there's a shop in texas who supplies and does the installation

check out www.dieseltoyz.com