i have a 2004 Dodge dakota 3.7 v6 that just blew are any years interchangeable? if so what years?

 

Welcome to the forum JWS.

'04 was the only year the 3.7 was available in the 2nd Gen Dakota. Later years "should" work but there were some changes to the cam. I'm not sure if they would affect the fuel mapping.

 

Would a 3.7 from a 2004 jeep liberty fit?

 

Physically it should fit fine.

 

ok but would a 3.9 fit? they look the same whats the diffrence?

 

No a 3.9 will NOT fit and it is no way near the same engine. The wiring harnesses are completely different and you won't find a PCM to fit your Dak. The 3.9 was discontinued in '04. You'd need new transmission too.

Put a 3.7 in. It is the easiest and cheapest solution.

Any boneyard should have an interchange manual to tell you exactly what engine will fit. Physically any 3.7 should fit but there may be changes to some of the components depending upon the year/model it came out of. Not a big deal, use what you have on your current engine.

http://www.car-part.com can help you find a replacment.

 

ok but before i pull the motor just want to make sure that i have a spun bearing When it starts up there's a little knock when you hit the gas it gets loud as hell oil pressure is good it runs smooth no lifters fell off anything else it could be? i drained the oil didnt see any shavings or metal.

 

A knock certainly could be a bearing. You can also have noise from a bad timing chain tensioner.

Try this, pull the connector to each coil one at a time and try it. Yes, you'll get some codes but if it is a rod bearing it should be MUCH quieter when you get the bad cylinder.

It might be worthwhile to just to drop the pan first and check out the bearing/journal. Then you can decide to replace/repair. It's odd for just one to fail.

 

it did get sligtly quieter until you hit the gas i know there is always issues with the 2 chains going to the heads but i checked them they are tight what about the main one? anything known to go bad on it? the truck has 190k miles on it 2wd and it does not seam like i can get the pan out without pulling the motor.

 

The chains can/do wear. They're rated for 250k miles.

Try disconnecting each coil one at a time though. It should narrow down what cylinder is causing it - IF it is a bad rod bearing. Really, there should be a noticeable difference in the noise when you find it. It only takes a few minutes to do.

Also, are you positive it is not an accessory or idler? Take the belt off and try it, just for a minute so you don't overheat.