Recently bought a 93 D250 Cummins with the 46RH, and it makes a whining noise in the transmission between 35-45 MPH and only when accelerating. The noise has been best described as like a power steering pump going out, but I am not sure what it is. Working on getting myself a FSM too because eventually I will rebuild it.

 

Should be a 47RH..... Last time fluid/filter was changed?

 

47rh is 94-95... And has lockup.

 

A 46 behind der diesel??? I didn't even think it would bolt up.

 

47RH wasn't in the 93 model year, and I don't know on the fluid/filter as the guy we bought it from only had it a couple months and it sat, and the guy he bought it from had it sitting for several years. My dad and I were planning on doing fluid/filter and checking the bands while the pan is dropped.

Yep, I think the diesel version has a different bell housing but that is it. I could be wrong however as I am quite new to autos, particularly in Dodge trucks. My dad has a 3rd gen 2500 Cummins, but it is a manual.

 

Learn somethin' new every day.

There IS a pump in the trans, and that likely IS what you are hearing...... How much longer it will last is anyones guess though.... Might last years, might die tomorrow..... Drop the pan, see if there is anything interesting in there. If it looks ok, change the fluid and filter, and run it. See if it doesn't quiet down.

 

A518... 46RH... whichever you want to call it. Diesel bellhousing is unique, and only the gas versions could have lockup.

 

Real curious for their reasoning for NOT giving the diesel a locking converter..... Seems like that would be the ideal place to actually have it.

 

beats me...

 

It's my best guess the size/design with the gas lockup TC couldn't hold the torque.

They figured it out for '94 (47rh) and that's why the adapter plate is ~1" thicker/deeper; to hold a beefier TC.