TKGN1

Just bought a low milage 04 model auto. Build date is 06-2004, I believe
HP rating on tag is 325hp. Question is how to tell difference between 04 and 04.5 for future mods? Anything to "look out" for on these year models?

Just noticed a previous thread asking the same question, got most answers there. Thanks for any help anyhow.

Locomotion

It's a 2004.5. All of them built in '04 are considered '04.5, like mine.

I have around 25,000 miles on mine now. Got it used also with only 5,400 miles a little over a year ago. Regularly serviced, no problems and I did have the smoke/mileage/overhead computer TSB done. Synthetics throughout and I get as good as 14.5mpg towing an open race car/trailer @ 6,000lbs.+. (Heavy car, trailer and large, full tool box.

Only thing I'm concerned about is the lift pump.

TKGN1

Thanks for the info. Other than the lift pump, any other issues like transmission(auto) probs? Is the lift pump a puller like 2nd gens? I built a custom pusher kit for my 01' and had excellent pressure even with mods, do the 3rd gens run on about same fuel pressure?

marc03

all 325 hp are 2004.5's. The 2004's were 305 hp. The only thing I really dont care for on my 325hp compared to my 2003 305hp is my 03' got better mileage and the egt's were lower.

Locomotion

I believe th '04.5 has cats and the earlier ones didn't, as well as an extra injection cycle. (Forgot what it's called.) That probably explains the mileage and temps. But I don't have gauges to monitor fuel pressure & EGT's.
Only mod I plan is to install the XZT I bought a while ago and not push it too hard when eventually getting to an enclosed car trailer.

Some people still are concerned about the 48RE.