I am looking to get my first truck and i have been doing a lot of research on the 06 5.9L and the 07.5 6.7L. I didn't know which is better i have read the pros and cons on both and didn't know which one i should get. Any info anyone can give me will help me a lot.

 

the 5.9 wont have all the exhaust crap for emissions

 

I know this is a technicality, but if it has a 6.7L, it is an 07.5 or later.

Given the choice between an 06 and an early 07.5, I would go with the 5.9L.

 

alright thanks, ya i have heard a lot about the early 07.5 that they had a lot of problems and a lot of people were forced to bring them back to the dealers while the 06 are reliable but lack the new updates for the emissions while the 07.5 have added extra HP and torque. also new was the 6 speed auto with 2 overdrives

 

I have an 07 5.9 - it has been flawless. Built in November of 06.

You could easily get an 06 or 07 5.9 and throw a smarty or an edge on it have have more HP and torque than you are used to anyway. Then you wouldn't have the hassle of the new emissions equipment.

 

alright thanks, if i was to get the 07 5.9L does it have 6 speed auto or is that only with the 6.7L? also with the 5.9L it passes the emissions?

 

4 speed auto-48re in the 5.9s...6 speed 68rfe in 6.7s only

 

if the engine is the same at 5.9L anything different between 06 and 07 models?

 

nope i have both trucks

 

Another plus to some (most?) '07 5.9s is the G56 has a slightly higher overdrive ratio. Mine is one, I think Roperteacher has one too.

There are some differences in an 06 and an 06.5 through 07 5.9 ECM as well. For instance a TST box won't work well or at all on 5.9's built after June 06.

Looking at my 5.9's fuse box you see spaces for equipment used on the 6.7. The guts just aren't there.

Smarty still works just as good though!!

 

sold my 06 5.9 g56 and bought 07.5 6.7 auto with no regrets. Happier with this one than any other cummins or any other truck ive owned.
mooseman

 

i have read about some problems with the 6.7 68rfe that they have been noticeably weaker than the 5.9 48re. is that true with anyone who has one?

 

I gotta be honest, given the chance to do it again I wouldn't be so scared of the 6.7

If you live in area where you don't have emissions to worry about, they've made HUGE gains lately in making these things super reliable, and efficient once you dump the restrictions. Plus, you get a bad*** transmission and exhaust brake.

 

yeah you make a good point and they get better gas mileage than the 5.9, but when you say dump the restrictions do you mean take them completely out of the truck?

 

No, they get worse actually. Much worse is the norm. Some people seem to do pretty well with them though. The restrictions I'm referring to are the emissions (EGR, DPF). Those two alone should help increase the mileage dramatically.