yeah im with ya on the if it aint broke dont fix it...but it just seemed like a good deal....and yea i was kinda thinkin the same thing b/c it seems like the 4.2 and 4.6 are pretty similiar

I just wonder when this thing goes would it be worth to convert to the v-8 or just stick with the trusty v-6....keeping in mind i dont do much towing ever....ha sorry for my many thoughts and questions

 

Your truck with the 4.2 has a PCM with only 1 connector. It incorporates the main body harness, the transmission harness and the engine harness. If you install a V8 you will have to replace the PCM and engine harness. You could do it one of two ways. Splice your new engine harness into the existing harness and repining the 104 pin connector at the PCM or replace the whole thing. To replace the whole thing involves removing all of the engine bay harness up to the bulkhead.

 

ha sounds like id be in way over my head

 

A 4.6 is far better than a 4.2. I've driven both, towed with both. The 4.6 NPI has better acceleration and gets about the same mileage. A 5.4 still has more than both.

The 4.2 came with a 4r70w or M5OD just as the 4.6 did. The 5.4 was available with the 4r70w or the 4r100. The 4.2's transmission does not have the same bellhousing bolt pattern, torque converter, and even has less clutches inside.

Really easy swap though. If its a similar year, most of the inside harness might match up to the v8 harness. And your 4.2 radiator is all set(same as a 4.6 one).

Don't let the harness scare you. Its really not that hard to take off. If your getting the harness and ecm with the engine, your set.

 

I have a 2003 f150 xl with the 5 speed and 4.2. I was wondering what would be the best swaps for this truck. Or what could I do to the v6 to make it have more power. If I swap what would I need for the engine. I'm think of going to the 4.6 or 5.4 N/A.



Ssgt Goss
Cap

 

Hello im new to this and wanted some help i have a 2003 f150 did a 4.6 swap to a 4.2 truck it cranks but fuel pump don turn on motor was from a 2001 expedition

 

I have a 2003 Ford f150 sport, automatic transmission and I found an 03 to 06 crown Vic interceptor with a 4.6 for $600 would it be worth it to make the swap

 

No.

 

oh wow, an upgraded oil cooler and alternator with zero performance anything added
x2!!!