So I hopped over from the Durango boards for the more active Ram boards since the motors are the same, and have my question narrowed down. I have been experiencing an rpm dependent vibration(both driving while parked) , and I think it is due to the previous owner swapping a 5.2 for the original 5.9. No clue why, and I don't think they did it on purpose. Since they didn't do it on purpose, I don't think they realized differences in the torque converter and flex plate for the two motors. Does anyone have input if this might be my issue, or a way to test it, or different ideas?

 

I have confirmed I have the 5.2 per the stamp on the block, the build sheet says it came with the 5.9, and they didn't swap trannies so it still has the original 46re as best as I can tell

 

Take a look at the balancer on the front and see if it has the 5.9 or the 5.2 one. I'm guessing if they changed it they changed the flex plate too and if they forgot they probably forgot the flex plate. Also if they didn't get that right or didn't know they changed to the 5.2 it has the wrong pcm.

 

I always assumed they got the right pcm with the motor I guess I don't know for sure. And how do I check the balancer?

 

It's too dark out and the pcm was dirty, couldn't get a number off it. Isn't the code that the 5.9 has a Z in it, and the 5.2...?

 

Well here's a picture from my how to rebuild your mopar magnum book, and there's a picture from my 360 where you can see a slot cut out. Basically a 318 has a solid balancer and a 360 has a slot cut out somewhere(it may vary between years).

 

OK I will be checking both tomorrow while it's light out. I can't imagine the balancer would have gotten changed, I would think when they dropped the 5.2 in they would have left it alone, which would mean it's the right one for the motor.

 

In 00, the balance weights for the 5.9 were on the flexplate. If they left the plate that was on the engine there when they swapped it, should be golden.

Not just getting a miss on one cylinder are you?

 

I think I mentioned it in my post on the Durango boards, but forgot it here. I think I do have a miss at idle, but never recognized it as a miss until someone brought it up. But it clears up, or seems to, above 1k rpm. If it is a miss do you think it could be coming back at high rpm to cause the vibratio? And do yyou think the miss is possibly a result of having the 5.9 pcm? I have yet to verify which one I have, will do it this afternoon.

As far as the flex plate, I have never had a motor that far apart. Is the order motor/flexplate/TC/transmission?

 

And the problem is I have no idea if they left the flex plate on. I know it's a junkyard motor but who knows if it's they reused the flex plate. I also don't know what year the motor is, it may be different. Is the year stamped on the block?