Cant say i have ever heard of any problems with the Navara lately??
I believe he is talking about the D22 engine that was causing issues in the 2002 - 2005 models.
A few friends have them as work vehicles one tows and one has clocked up 120,000 in 3 years. None have had any issues only a recall for alloy wheels that may crack?
The ones who tows gets around 18mpg with a twin axle,but tows very well with no issues, he likes it so much he has just ordered a new one.