I have an early 2003 2500 with a 47RE. I want to change the filter and fluid, changing more fluid than is in the pan. I would like to replace the filter, replace the fluid in the pan with new fluid, and then pump (by starting the engine) the remaining fluid out at the radiator or the return line at the transmission.

The question is, is it easiest to pump it out at the radiator or the transmission. I'm not sure which of the hoses(tubes) at the transmission is the return line. Also, would be a pain in the butt to do.

As far as doing it at the radiator, I'm assuming the cooler at the front is the transmission cooler and after looking at the fittings on the front I'm not sure how they work...there appears to be a screw plug in the entry and exit to the cooler.

Any help would be appreciated.


Note: Is it possible to pump most of it out of the fluid filler hole with a hand pump which I have?

 

I think you could probably flush most of it out by taking one of the cooler lines loose and blowing it out with air?

 

Do a search. There are alot of instructions on here. I have never heard of blowing it out with air. I wouldn't do that. It seems like most of the things I have read on here refer to disconnecting the return line and putting running the truck in neutral. Pump one quart out shut it down and add one quart. Continue this until you have run about 16 quarts through it. I'm recalling this from memory so there may be more to it so do a search. I'm sure someone else will chime in with a more accurate version. I would stay away from the air though. Just my opinion.

 

Here are a couple links on doing your own flush:

DIY Flush:
https://www.dieseltruckresource.com/...91%3Cbr%20/%3E
https://www.dieseltruckresource.com/...ighlight=bands