Im 16 and own a 1989 dodge Dakota 2wd auto 3.9L and the engine runs fine but needs a tune up and all the gaskets replaced but while its out (which i need help on the removal part) i would like to slightly rebuild it and make it look good so what do you guys suggest replacing and is it worth it to rebuild it it is my first truck and it means alot to me and would like to hit 1 million miles with it, it only has 128,000 so i got awhile

 

Why are you pulling the motor? Modern engines are lasting a lot longer than the old days....
Had a machine shop tell me that the heads need work at around 125,000 miles and then they are good to go for another 100,000 miles.
but if you are pulling it because some inaccesible seals leak, then by all means replace freeze plugs, tranny front seal, motor front and rear seals, oil pan gasket, etc. There aren't a lot of performance parts for the v6 but if you want it to feel like it has a v8, look into the rear axle ratio. You most likely have the 3.55 ratio, and a 3.92 will be an improvement in driving fun without costing a lot in increased gas consumption.

 

thanks and yeah i think the engine is leaking oil out the main seal and the trans is leaking out the front

 

do a compression check, if all 6 cylinders are good, don't rebuild the engine....just take care of all the leaks.

If a cylinders has low compression, squirt some oil into the spark plug hole and test again. If the pressure remains low, look into a valve job on the heads.. if the pressure goes up, piston rings are likely in need of replacement.

Find out exactly what is broke before tearing into it....saves a lot of headaches...

 

do you have to have the engine in the truck to do the compression test or an you do it while its out the engine also has somewhat of a knock and tick i also plan on doing a whole gasket and seal replacement new bearings main and rod also ale guide seals and also rings but if it dont need rings that would make it easier but would they go bad later

 

a compression test requires cranking the motor with a pressure gage stuck in the spark plug hole, so yes. If there is a knock, different ball game.
Before rebuilding this motor, look into buying a used one from a reputable junk yard.
The newer v6, from 92 to 2003, are MUCH better engines....problem here, tho, is the intake manifold. There are none for Throttle Body fuel Injection for the magnum v6. THere are maybe a dozen made to be used for carb or TBI with adapter plate. I had one of the few, and I sold mine a few months ago.
The v6 just isn't that popular an engine so performance parts are not available...
The best bet is to drop in a 5.2 magnum v8. There are carburetor intake manifolds for them that you can put an adapter plate on top of, and use your TBI. The 89 Shelby dakota had a LA version of the 5.2, and it used the v6 front springs, so this is an easy way to get serious horsepower in your truck. There won't be room for a fan blade so you will have to put an electric fan in front of your radiator/condensor. DOes it have air conditioning?

 

well i don't really are for more power i just want a reliable engine it doesn't really have a knock it is more like a tick im thinking of getting the re ring kit that comes with gasket and seal kit rod and main bearings and rings its like $200 from rock-auto i don't really want a v8 because its expensive and then i would need a new trans and then it would get complicated

 

The tick could just be your timing chain.

 

If just a tic, that is probably in the valve train, and a valve job on the heads is a good idea. Is the truck still in one piece? Make sure the tic isn't the oil dip stick getting hit by the crankshaft. Just lift the dipstick an inch while the engine is idling. I have seen that before.
The v8 will get almost the same gas mileage, USES THE SAME TRANNY, and performance parts are plentiful....for later on.
Last time I will say this, make sure you know what is NEEDED before tearing into it....

 

I understand the complication aspect, that is why I have been offering the least compllicated path, or paths, to take. Rebuilding an engine gets very expensive, there is only so much you can do yourself, and the machine shops are not cheap.
You can use the same tranny, same motor mounts (if you use a magnum v8), same radiator, same TBI (with larger injectors), and probably the same computer, altho I am not sure of that last part. But they aren't that expensive.
My 89 came with a 4 banger, so I needed a lot of different stuff. Yours can be easy, if you listen to the more experienced members here...