First, if you have not already done so, is do a search. You will read for two days.
Second, it is a "peace of mind" question. How do you handle an engine/transmission problem?
Third, do you have $4000 or more for a 4-5-6 year extended service contract ?
2003 Dolphin LX 6355 w/ W22 chassis; 8.1L gas & Allison 1000