Hey everyone, first off I'm going to have to admit that I'm a hard core Chevy guy but recently inherited an 89 Dodge Ram D100...heres the story.

My grandfather bought it new in 88 to use for his heating and a/c business. After hauling around literally a ton of equipment for the past 20 years or 322,578 miles the poor little mountain goat finally bit the dust "bent pushrods". Well he then gave it to my 18 year old brother to "fix it up" but my mom told me last week he was planning to sell it for scrap so I decided to rescue it and now it's sitting in my yard.

It has a 3.9 tbi motor in it, and a friend of mine told me he had a fresh and running 5.2 with new transmission out of a 94 ram sitting on his engine stand that he would sell me for $50...I've seen the motor run, it was rebuilt along with the transmission roughly 2,000 miles before the truck was flipped.

I've been told that the motor and trans would be pretty much a direct swap except for the ecm, I've done a lot of searches here and can't find anything about it...not even if i just type in 3.9 or 5.2 or 318, all I can find is stuff about headers lol.

A link to something helpfull would be appreciated.

 

I don't think it'll be such an easy swap.... Why don't you just replace the pushrods and RR, new rings and run it toll the frame rots away?

Just a thought....

JimK

 

Thanks, I've considered a rebuild. But hey I have tons of time, a fab shop, and a new 318 with a new transmission for $50 to stick it in lol. I simply know nothing about dodges and parts interchangability and thats more along the lines of why I'm here.

 

well, you'll need the computer for the 318, and then, you'll need the wiring harness for the 318, and it's going to be a bastard to retrofit that crap into a 89.. Your honest best bet is to rebuild the motor, or just sell it and get another truck... Not saying it can't be done, it's just a bastard to do, and not sure if it's something you really want to get into..

I couldn't tell you what all you'll need or not need other than what I mentioned above, I am not that good with these newer vehicles, I am OLD SCHOOL.. But I am about to learn, with my 2000 DOdge Ram I just bought..

JimK

 

Lol whats the plans for the 2000?

I just got the motor and trans to my house, looked it over really good and it appears the 3.9 wiring harness will swap right over to the 318, might have to lenghten a few wires but otherwise they go plug for plug, the 318 even came with motor mounts that are going to work and all of the accessories are the exact same too!.

As far as difficulty goes I think it's safe to say this is going to be smooth as butter. After all it's nothing but parts+bolts.

 

Don't forget the computer, that is MOST important... It will not work without the computer...

Hope it works out good for ya.. I am going to be getting the tranny fixed soon, as soon as I get it towed to the guy who is going to fix it. And then I'm going to start tweakin, adding 1.7RR's, and a new TB, a nice intake kit, just a few things to pump it up a bit, don't want anything too major, but figure I can make it a little better than stock, and I'll be happy.. The rest is cosmetic, body work, lightbar,Rhinocoated bed, blah blah.. I may end up putting in a performance computer, I don't know.. We'll see.. It is going to be fun... I miss the old days of getting grimy and dirty with little fear of computers and vacuum lines.. hehe...

 

Sounds like it's going to be a nice build man.

I've gotten everything from the 3.9 swapped over to the 318 right now, thats all of the accessories, sensors, wiring harness, and even the water pump. The two motors are basically exactly the same on the outside except for the exhaust manifolds and distributors. From what I can tell even the ecm is going to be the same, all of my part number searches say it will work for a 3.9, 5.2 and 5.9 as long as you use the same transmission. Right now the only thing holding me up from dropping the new motor in is the passenger side exhaust manifold is missing a tab where the collector bolts up.

I've never really done anything like this on a Dodge before, I'm super suprised at how easy it is to get the motors out on these things, basically it's just four harness plugs on the passenger side of the fender well, trans lines, power steering lines, exhaust, shift linkage, drive shaft, throttle cables, starter wires and a few ground wires and it's ready to come out.

Another thing that suprised me was that every time I pull a bolt out of the motor coolant comes out lol, I guess every single bolt is drilled into a water jacket lol, so I made sure to silicone every single bolt when I put them back in lol...flippin weird lol

 

yeah, gotta keep those bolts from overheating, so Dodge made sure coolant gets to every one.. hahahaha.....

Please keep me posted, would love to know how that turns out... I thought about getting a 3.9 and dropping it down in mine, although mine is newer than both your engine and truck, so not sure how similar it will be, but thought I might do that so I can really tear into this 5.9 and do it up right, get the block honed and polished, really do a nice job on it... Anyway, we'll see...

 

Finally got some pics of what I'm working with here, Got some headers on the way since the pass-side exhaust manifold is cracked, Jegs sells headers cheaper than the junkyard sells manifolds around here. The 318 is fully dressed out now except for headers, And yeah those are 17" Rims off of a 99 Ram R/T lol. My 72 year old grandpa told me that he wants to see it "lowered down like the mexicans do" lol, fine with me! Oh and he also said whenever I get it running and let him drive it around a bit he'll get the Ram's head hood ornament out of the closet to put back on, I broke it off 17 years ago lol.