The 6.4 tows better, more about the TQ than the HP, a 5.7 downshifts a lot without a trailer, my 6.4 (not exactly stock) pulls way better than a 5.7. I actually buy 5.7 trucks with bad engines and stick 6.4s in with a simple upgrade recipe that is much better than even a stock 6.4.

If your willing to build a truck up the best combo seems to me to use a 6.4 truck short block, 6.4 SRT8 injectors with 5.7 heads, intake cam... as the 5.7s make more TQ per CID than the 6.4. This also gives you more compression than a regular 6.4 truck and is a beast for towing, I currently have this exact combo in my 2011 4x4 4 door long bed and towed an identicle configuration truck on a heavy 20ft tilt-deck trailer and even going up a couple big mountain grades only un-locked the TQ converter and did not downshift. I got 11.5 MPG towing that truck. It pulls even better than an actual stock 6.4 truck and cost about 1/2 what one of those trucks would cost. The real 6.4 trucks use EGR witch I hate, the 5.7s don't have it.

I did one with a 6.4 SRT8 engine and it pulled even better but it liked to run much higher RPM also, this current one is much more satisfying when pulling.

I would not run the early 5.7 heads as they will lower compression quench and flow... I am running eagle 5.7s that give it more compression. If you really want to run the early heads then you should get an SRT short block because of the dome pistons.

The 6.4 tows better, more about the TQ than the HP, a 5.7 downshifts a lot without a trailer, my 6.4 (not exactly stock) pulls way better than a 5.7. I actually buy 5.7 trucks with bad engines and stick 6.4s in with a simple upgrade recipe that is much better than even a stock 6.4.

If your willing to build a truck up the best combo seems to me to use a 6.4 truck short block, 6.4 SRT8 injectors with 5.7 heads, intake cam... as the 5.7s make more TQ per CID than the 6.4. This also gives you more compression than a regular 6.4 truck and is a beast for towing, I currently have this exact combo in my 2011 4x4 4 door long bed and towed an identicle configuration truck on a heavy 20ft tilt-deck trailer and even going up a couple big mountain grades only un-locked the TQ converter and did not downshift. I got 11.5 MPG towing that truck. It pulls even better than an actual stock 6.4 truck and cost about 1/2 what one of those trucks would cost. The real 6.4 trucks use EGR witch I hate, the 5.7s don't have it.

I did one with a 6.4 SRT8 engine and it pulled even better but it liked to run much higher RPM also, this current one is much more satisfying when pulling.

If you are on a tighter budget and want a newer Ram truck why not look into a repaired "prior salvage" one? You said you would likely have it a long time. That way you can get a better newer truck with less miles on it. I have been building and driving them for 10 years now. Great value! Why spend 30K for a clean title one with 100K miles, Instead spend 30K for one with only 30k miles that will give you years of service before needing anything replaced. They aren't all total nasty wrecks that need fixing either. I had an 18 2500 Cummins with 44k on it last year that someone put in the ditch and bent the front axle. No paint or body damage at all. Replaced the front axle and did alignment and it was good to go!

Oh, I hear ya. I see plenty of guys that like to cut corners on repairs. I would just say to ask plenty of questions and get a feel for IF they cut corners or have a pro inspect a possible purchase. I get plenty of repeat customers and referrals because I do things right. No aftermarket parts, and drivetrain parts that are similar or less miles. I just fixed a 2018 Cummins that got sunk 4 ft in a pond. Sucked water into 1 cylinder so I replaced the engine with one with only 39K on it (truck had 46k). replaced every single electronic part and wiring. Brand new dash and full cab harnesses to the tune of over $1200 alone. I had an 18 Ram 3500 6.4 shortbed that got hit hard in the front, only 18k miles., Big Horn. Bought it for only $8,100. I bought a brand new frame for it for $2100 along with new Mopar fenders, hood, and RH doors. Sold it about when the pandemic started. I'm sure the guy that bought it is quite happy with it.

[quote=hemi70se] ...


Not everyone putting trucks together is doing a good job, that's why they are so frowned on. ...