bama

hate to ask a long winded question,but what is the differences in the 03 and 04 motors?and im only talking with a 6 speed manual tranny.im looking at some used trucks and would like to know the differences and what to look for.thanks,bama

HorseHauler

03 has 2 options, the SO motor which was 250hp 460 tq and the HO which was 305 Hp and 555 tq. the early 04 all they had was the 305/555 motor and then in 04.5 the 600 motor came out.

midwestdually

look me up bro..i will tell you all you need to know

SuperGewl

Actually you are incorrect. The 03 had 3 motor options, the SO CA (235hp), SO (250hp), & the HO (305hp). The 04 had the same . The 04.5 only had one the HO (305hp), the 05 only had 2 the 305hp & the 310hp.

Graphite600

The 05's have 2 options, early early 05's may have the 325/600 engine, and current 05's have the 325/610 engine.

J BODY

04 up has better diagnostics.

mikmaze

and rumor has it if ya flash the tsb on a 600 motor to 18 037 004 you have a 610 torque motor

Original Junior

No cats on the 03's either. I don't think the cats came until the 04.5 600s. Also my 03 came with a 3 inch exhaust which I replaced. The 600s come with a full 4 incher. Check here to confirm this but I hear that the 555s run cooler on the EGT side but produce less boost than the 600s.

bama

thanks fellas,,,,,,,,,now back to shopping

budsowner

Actually the 04.5 has (325hp).

roadrat

The change from the 305 hp. 555 ft lb. to the 325 hp. 600 lb. was jan. 1/04, so if your not sure which 04 you are looking at check the sticker on the side of the valve cover, or the build date on the sticker on the drivers door.

rob