2003 hemi differences

[Redtruck-VA]

The cats was mentioned as a big difference as the 03 has only one large one immediately in front of the muffler. Where as the 04 has two smaller cats located on the mid pipe behind the exhaust manifolds before joining at the "Y". This is why when looking at purchasing headers it usually states 04-05 models excluding the 03. The headers are the same, but the mid pipe (Y pipe) is different. Long tubes, you are fabricating your own pipe's and using the Off Road Y (ORY) is the way to go. The original 03 cat can be used or duals cats installed behind the collectors by modifying the ORY pipe. The 03 cats outflow anything out there so a pair of those really work well. The 03 has only one forward O2s and one rear O2s, where as the newer models have two forward and two rear. There is no issues associated with using only one O2s reading from one side of the engine. There is some differences with radiator reservoir tank, the 03 uses a power steering pressure switch that controls idle speed, that the newer trucks don't have. For tuning, there is no idle, rpm or speed adjustments available from DSP (CMR) tunes. SC3815/3865 can adjust the rpm and speed limits. DSP has corrupted more than one PCM causing anti-lok (ABS) sync issues when adjusting tire sizes. SCT supports 03/4.7, but not the 5.7. I believe for hard core DIY the 03 is easier to work on then the newer trucks. I'm just rambling this morning so bare with me....

 

[mcraezy87]

Are you saying you have done the TB drive by cable conversion?

Naw Greg, sorry for the confusion. I merely meant I was interested in how that one fellas friend converted his as well.

 

[Redtruck-VA]

I would be interested in hearing about anyone doing a "drive by cable" conversion.
Thanks,

 

[frostking]

Another odd fact for the '03 trucks. I recently installed a HD tow hitch on my truck and the early '03s have a different part number than the late '03s, so something on the rear frame changed mid-year. Also my truck will be rocking all-terrain tires for towing my new Can-am Commander, so it's racing days are officially over.

 

[Redtruck-VA]

Another odd fact for the '03 trucks. I recently installed a HD tow hitch on my truck and the early '03s have a different part number than the late '03s, so something on the rear frame changed mid-year. Also my truck will be rocking all-terrain tires for towing my new Can-am Commander, so it's racing days are officially over.

Sorry to hear you are retiring the truck from racing. I have a March built 03 and I believe some of them had/have a harmonic dampener installed which might have required a different hitch. Hope you didn't buy the hitch as I have my original laying around here somewhere.

 

[rabbie303]

3. There is a short Vent Hose that goes from the Hemi-Hat to the Oil Cap Filler Assy on the Valve Cover (04 up hose crosses from the Air Filter Box assy);

Can anyone tell me the actual name of this hose? I've called Dodge and they either have idiots or they don't understand that I'm talking about, but they first said the part is included in an entire manifold setup for $400, and then they said "it's a $22 hose" which still seems high.

I've looked and I can't find the exact name of this damn thing.

 

[Redtruck-VA]

I agree $22 for a simple rubber hose is too high. I would call it the oil filler tube rubber vent hose. It actually vents the crank case not the oil filler tube. So maybe the crank case vent hose.