I just did an engine swap on my 1997 Ram 2500 (5.9 gas auto trans.). I left the trans. in place (supported by a jack stand) during the engine swap).

The trans. worked fine and made no noises before the swap. But now it makes a rattle noise especially right on start-up / warm-up. Also, it seems to be a bit underpowered in reverse.

When swapping the engine I pulled the dipstick tube and lost a bunch of trans fluid but I don't know how much. I tried to do the trans fluid fill procedure and ended up adding about 2 quarts (more than I thought I had lost). I did the fill procedure in park, but I just read on here to do it in neutral (I thought park was neutral as with most auto transmissions). I checked the trans. again with the truck warm and idling in neutral and it still showed "good" but on the low end of the range.

Could it still be low on trans fluid? I'm not sure what's rattling in the trans but the fluid is the only thing that has changed since the engine swap.

Any help would be much appreciated!

P.S. I utilized this site several times during the engine swap for help. Thanks to the great members and admins on here!!!

 

could the flex plate be hitting the dust cover ?
i had that cover off and didn't get it hooked correctly when reinstalling, and it made a banging sound when i started it up.

or - could one of the torque converter bolts have come out?

 

That would be the first thing id check.