So my Ram was due for a transmission service, and rather than take it to the dealer I figured I'd follow the DIY @ https://dodgeforum.com/forum/4th-gen...-flushing.html and save some money. I've done transmission fluid changes before and haven't had issues, but this was my first time doing the "exchange" method.

So everything was fine until I got to step 7. When I started the truck up to drain out ~6 qrts of old fluid, I just got a bit of sputtering out of the return line, with not more than a qrt of liquid having come out. Also the CEL came up - unfortunately my code reader is a couple hours away so I can't determine what code has been tripped.

I didn't buy Mopar filters (got some ProKing ones from PartsSource), and the first time around I didn't bother changing the flat filter seal. Thinking this might have been the issue, I dropped the pan again and pulled the old seal, installed the new one and made sure the filter was seated correctly against the valve body. I also carefully inspected the old and new filters prior to install and they are the exact same (in terms of dimensions).

Having the pan bolted back up, I again dumped 7qrts of fluid in and started the truck up, had it in gear for a few seconds, then back to park. This time I got a bit more fluid out, but not near the 6qrts like I was expecting. It seems like there isn't much pressure coming out of the return line so I'm wondering if the new filter isn't allowing the fluid to get sucked up and circulating like it should.

Anyone have any ideas? Should I run the truck and feed a bit more oil in to see if that will help push more out? The dipstick is reading at the hot level, despite the truck not being fully warmed up, so I don't really want to overfill it. Also need to get to work tomorrow morning so I'm running out of time! Help is greatly appreciated!

 

I guess a more specific question would be if I should have 6 quarts of liquid shoot out of the return line after pouring the 7 quarts into the pan as described in step 6? The big thing Im worried about is the fluid not being circulated, but right now there is pressure coming out of the return line but not much fluid is being expelled (it has air mixed in hence my concern that there's an issue with the filter). Also I disconnected the battery and the CEL hasn't come back on since I reseated the filter so that could be a good sign. I just don't want to drive the truck around if fluid isn't being circulated as it should.

 

After more research I'm wondering if the low pressure could be due to me not priming the screw on filter. I wouldn't think you'd need to prime it, but that would make some sense. I decided to take her for a spin around the block to see if that might work the fluid through and get things running correctly. I made sure fluid levels were where they're supposed to be and took it easy. The truck drove better than it did before, so I'm hoping when I pop the return line tomorrow morning it will flow like it's supposed to and I can forget about this stupid issue. If it doesn't I suppose I may have to drop the pan again and replace the filters with Mopar.

Also, now when my key is set to "on" but the truck isn't running I get a CEL that's solid then flashses 10 times, then goes back to solid but turns off when I start the truck. I did the "off on off on off on" to check for a code but nothing is displayed.

 

Turns out these 4th gen Rams have a thermostat in the cooler that restricts flow to the return line, so the DIY in these forums isn't an accurate guide for 4th gens unless your fluid is over a certain temperature. Instead of using the return line I disconnected the supply line just before the cooler and drained the old fluid through there. Someone might want to make a point of adding that to the DIY to save other people attempting their own fluid changes the same headaches/worry that i went through.

 

I apologize about that. i've never done my Ram, so it very well could be the same as yours. I'll make the correction.

 

Not a problem - just had a little stress and mental breakdown but all is good now! I believe (from my extensive researching the last 3 days) that it's just the 4th gen Rams that have the thermostat. From others' descriptions of this drain method it sounds like older versions of the 545re would follow the procedure you outlined (as might 4th gens if running hot enough). Maybe if others with 4th gens have tried the "flush" they could chime in also.