Rig: 96 Safari Trek on 95 (OBD1) chassis
Driveline: 6.5L TurboDiesel (GM) w/4L80E tranny, 23.5K miles
Symptom: started sputtering, then over next 300 miles, got worse till it wouldn't run reliably.
Troubling factor: we were 650 miles south of San Diego
Problem: electronic fuel injection
Problem getting a good diagnosis: GM service rep in La Paz stated elegantly, "We never sell dat chit down here." (He was referring lovingly to EFI, they have plenty of diesels, just not electronics).
Fix: return to USA to get OBD1 computer & spare parts; return to Mexico to try parts & read computer codes; return to USA to get new electronic injection pump; return to Mexico to install.
Moral: for 6.5L GM diesel, subscribe to TheDieselPage.com, and keep a good sense of humor well oiled. And of course, take spare EVERYTHING to Mexico.
See y'all in Yucatan in '06.