I have had an early 1999 7.3 SC, DRW an early 2003 6.0 SC, DRW and an early 2008 6.4 CC DRW. I have pulled my 5Rs with all of them and each one got better as new trucks do. I liked each of them but my 6.4 is still the best and it has all the toys to make driving it that much more fun. I highly recommend the 6.4 and but the other two did the job and they all put a smile on my face every day.