I have a 2006 CTD with 4 spd auto trans. I am planning on changing my trans fluid soon. I am also planning on replacing the stock pan with a Mag-Hytech pan. I am going to replace the stock fluid with Amsoil fiud. I have read a number of different post concerning the fluid change. Some people say they just drop the pan, replace the filter, & refill. Other people say they unhook the lines that go to the trans cooler and flush everything after they change the fluid.

What do you guys do? Any advice would be great.

 

You can't beat flushing out all the old fluid and putting in all new, synthetic fluid. (Of course, when a shop does a flush, they do NOT drop the pan and replace the filter, but we are better than the shops ). A pan drop, filter change, and add to "full" only replaces about 25% of the fluid.
I know, I don't own a CTD (or a Ram for that matter) just my $.02.

 

to properly replace all the fluids you would have to have a few gallons of fluid, remove the cooler hose going from the tranny cooler back to the tranny and put that line into a bucket, crank the engine and put it into neutral so fluid is being circulated and begine pouring the fluid down the tube at about the same rate it is going into the pan. when the fluid becomes clear red turn the engine off and reconnect the line. then fill to full while engine running in neutral.

that is realy the best way to do it since you are also removeing the fluid that is in the torque converter. now you still wont get it all, but you'll get a good portion of it.

my opinion, the fluid on your 06 should still be good, drop the pan and put that maghytec pan back on, fill to full and be happy. there no need to replace the fluid yet.

 

How often should I change the fluid? I am getting close to 30,000 miles.

 

The '06 service manual says that, "schedule B" servicing is every 30,000 miles (a drain and refill tranny, change filter and adjust bands).
"Schedule A" is do that service at 100,000. Basically, I would go along more-so with the Schedule B.
Drew is right... with your being an '06, there probably isn't a need for a flush yet. (I must have skipped over where you said the year of your truck).

 

I have an 05. I changed the fluid at 20k miles. I dumped the pan, changed the filter, installed the mag hytec DD pan, filled it with amsoil, removed line from cooler, started the truck, had to put it in neutral to pump. I never saw the color change(the old fluid didn`t look bad) after I went thru about 5 gallons, I figured it was good. Now I have 42k miles and getting ready to order 5 more gallons of amsoil.

 

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5 gallons huh? Wow. Thats a LOT. But, thats actually about what it takes. The "dry fill" is 4.25 gallons, so an extra 3 quarts to make sure its all new fluid is ok. (Never thought of it in terms of gallong before