A '94 to '02 V10 2wd in either auto or standard would get my vote for most reliable. The V8's are close behind.
I don't have any miles on my 3rd Gen, but the '06 and up 5.7's with 545rfe address almost all the mechanical weaknesses of the 2 Gens. I believe the TIPM module is their greatest downfall but it's easier to deal with than the previous generations RE transmissions.
Loved my 98 2500 with the v10. It was a 2wd. That truck was comfortable and smooth driving. My only complaints were the brakes sucked when towing my trailer and with the cruise on the rpm would fluctuate up and down for no reason.
Owned it for 7 yrs and sold it when I bought my 2018 cummins mega cab. Took a long time to find a 2500 that was 2wd but I did. It puts a smile on my face every day I get in it.
