Hey all,

New member here. I had a '02 Dakota with a 5.9 back in high school and college, and couldn't pass up this deal I found this weekend. '03 3.9 v6 quad cab 4x4 with a blown motor and '97 3.9 v6 extended cab 4x2 with a good motor for under a grand. Both have been sitting for 2 years as the previous owner never got around to do the motor swap. the '97 turned over and started up just fine with a jump pack. It may be missing on one cylinder as there's a very slight tick.

First and foremost, I am NOT a mechanic, but I am definitely trying to learn more than just oil changes, etc. I have a mechanic friend who is going to help me, but the overall idea is to swap the motor out of the '97 and into the '03. We may look at rebuilding the '03 motor after that, but first priority is getting a running truck on the road.

I've been doing some research, and when I thought I found something, I was disappointed to learn that was for a 1st Gen, not 2nd gen, so I assume this post is out of the question for me. I also checked the FAQ, but unfortunately a lot of the links are no longer valid.

Overall, I'd like to do some simpler performance upgrades while we are doing the engine swap, but not exactly sure what anyone would recommend (that's easier to complete and not quickly more expensive than my entire purchase). We plan to replace the gaskets in the '97 motor, and then of course all new fluids (off top of my head: motor oil, transmission, brake fluid, transfer case, coolant, fuel, please chime in if I'm forgetting any). Also plan to get new brake pads(potentially rotors once I take a peek), tires (starting to crack), and filters (oil, air), but I don't have any real plans beyond that.

If anyone has any tips, ideas, or recommended parts (brands, weights that run well in the 3.9, etc.), I am all ears. I hope to just use this thread as a running update on the process and outcome.

Thanks for having me!

2003 3.9 SXT 4x4

1997 3.9 4x2

 

They were still using the 3.9 in 03?? Wow.

Probably need the tins off the original motor as well. (oil pan, anyway.) But, the stuff they were talking about in the other thread would apply to your engine as well. Things like shorty headers, 1.7 ratio roller rockers, etc, would certainly help. But, when it comes to performance, nothing is cheap. The truck looks to be in really good shape, so, just dropping an engine that runs into it is going to boost its value significantly.

 

Thanks! I am hoping to get it running decently and then go from there, but don't want to overlook some simple things to do while we are moving engines anyway.

One friend mentioned replacing all hoses since that's what will strand me on the side of the road. So I have added inspecting the existing hoses to the list to see what needs replaced.

 

Hoses are cheap, just replace ALL of them. Flush the radiator and heater core really good while you are at it.

Have you consider dropping a V-8 in, instead of the six?? 5.2 or 5.9 will bolt right in, just need to add wiring for two injectors, and maybe extend wiring for a couple sensor on the front of the motor, and then flash the pcm for the V-8..... THAT would be a significant performance upgrade.

 

I'd love to upgrade to v8, but that'd throw a wrench in the budget aspect of this real fast. Wife already isn't thrilled I bought these trucks with the donor v6 that came with it.

Noted on the hoses. I'm sure my accountant is showing. Give me numbers and it's my language, figuring out parts etc for a engine swap and it mind as well be another language. Gonna need to find me a list of hoses to order from rockauto haha

 

Well, we ARE good at spending other peoples money here. I think it's one of our favorite passtimes........

 

Can't blame you! Typically one of my favorite pastimes as well.

Quick question. I understand I have the 42re tyranny with the 3.9 4x4, but do you know if the rearbrakes are drums or rotors? Trucks are at a friend's house as we wait for barn space to open up

 

That, I don't know. I know they went to four wheel disk standard at some point, but, couldn't tell ya just when that was. The 96 is highly likely to be drum though. The newer one, I just don't know.

 

Yep, my 2003 has the 3.9L, at least at the moment. The brakes can be drum or disk in the rear for a 2003, but before 2003 they would have been drums. You may also have rear wheel antilocks or 4 wheel antilocks as an option. While the engine is out, I would replace the oil pan and valve cover gaskets. This is another problem my truck has, the valve covers leak. Gaskets aren't expensive, but replacing them can be if the engine is installed. The valve cover gaskets cost the same whether the engine is installed or not.

So far as performance parts for a V6 go, that's a bit harder. Performance parts companies concentrate on the largest engines that come in a model, and the V6 was the small one. One of the big changes you can make is replacing the mechanical fan with an electric one. Every vehicle I've made the conversion on has had a mileage and seat of the pants improvement in power. I didn't run before and after dynos, but I'm also one of the few that won't say "I paid X amount, it must be better" types. While the clutch fan uses less power than a fixed fan, it does use power and that power is noticeable. A free flowing exhaust, no more than 2 inch diameter duals or a 2.5 inch diameter single would also help. You can make it run better than the other V6s, but that's not saying much. If you want a real power boost, a turbo would be your best bet, but even then you'll want to build it for boost if you want to crank it up. By the time you buy a turbo and rebuild the engine, you'll have V8 money in the truck, and the V8 will be faster and more reliable. The turbo can be made to run faster, at the expense of reliability. Hope some of this helps.

 

Thanks for the comment!

Thankfully, I went a checked and it has rear disk brakes on mine. The PO had gaskets already purchased, so thankfully he gave me those and we plan to swap out when engine is out. I may still buy an entire engine gasket kit for the $30-$50 it'll cost me so we have all of them in case others need replaced.

Good note on the oil pan. I'll add that to my list. For the fan, do you have a brand or anything you would recommend? I have never messed with fans before