Okay, well, a while back I changed the fluid and filter in my transmission, and I had been reading stuff. Some people have sad that when you flush the transmission, it could sort of 'loosen' up some deposits inside the transmission, and could cause trans failure, but only if you haven't had it flushed regularly. I wasn't sure if mine had had that done, so I just changed the fluid. My truck had about 95K or so on it when I did it. I was wondering when I should do it again, and if I should have it flushed, or just change it again. Any info would be appreciated.

 

i work for an OEM filter manufacturer, we do all of the design testing,and the concensus is that back flushing a filter is not as good as some may say.the filter structure and filter mediaare designed and tested with temperature dependant time duration requirements, efficiency, contaminant capacity, ect...... not changing the filter at the required mileage/time can and may exceed the design criteria for the filter. media does deteriorate over time andcan develope holes in it. even if the media has not been compromised the filter capacity is diminished when back flushed because not allcontaminants are dislodged and removed from the filter media. this increases pressure drop across the filter and increases the chances of media failure because of the extended time duration to change. of course back flushing is better than not doing anything at all but really not agood practice no matter what you hear. i havent bothered finding out why backflushing the transmission was even started. probably because of all the front wheel drive cars and suchwith the inaccesibilty of the transmission pans to even change the filters. it also is a pain in the a__ to change a filter without a drain plug. my 2 cents is put a drain plug kit in your pan and change the filter every time you change the filter.

 

oops typo. i meant change the filter every time you change the oil.

 

I don't think he was talking about flushing the filter.

Silver

If your tranny hasn't been flushed then there is a build up of varnish on the clutches. The varnish replaces the normal friction material and will actally keep friction between the clutches. If you flush a tranny that hasn't been flushed before then your will clean all of the varnish off of the clutches. This will cause your transmision to become very loose and in need of a rebuild to replace the clutches. If your transmision has been flushed regularly then there won't be any varnsh on the clutches. The safest way to tell if it's been flushed or not is if you've done the service since it was brand new. Since you bought your truck used you have no idea if the previous owner ever flushed it. If the flud in the transmision is clean and not burnt you could maybe get away with flushing it on the assumption that it has been taken care of. If the fluid is burnt at all then you should avoid doing a flush.

 

i just reread the question. your right. my bad.

 

Cool. Thanks to both you guys, and yeah, I changed the filter and the oil, but that was just something that i've been thinking on. That's kind of what I'd heard before, ICEMAN, thanks for the additional info.

 

here is my opinion. if the transmission fluid has not been changed regularly, and/or its black or smelly, then you should simply change it a couple of times, a couple weeks apart, and then every 15-30k miles after that. i think trying to flush it by disconnecting a cooler line is too much trouble and a waste of fliud/money. i think having a shop do a 'power flush' is just too risky. its also a good idea to put in a drain plug to make the job easier.

 

ahh, this is the reason I've been avoiding changing my tranny fluid. So you're saying as long as I don't flush it then I should be okay? I mean it's not urgent anyway, the fluid is still red and clear and doesn't smell burned or anything.Also I was thinking about switching to synthetic, is it okay to do that without flushing it or should I just keep regular tranny oil in there? I want to run synthetic in the transfer case but I don't want to have 2 different fluids in there just incase the seal ever breaks.

 

i think its best to run the atf+4 thats recommended by dodge. its already a synthetic.
http://www.valvoline.com/pages/produ...asp?product=63

keep it cool and keep the fluid changed regularly and hope for the best. that's all you do.

some will say that if a tranny's already got 100k on it and the fluid hasn't been changed then you shouldn't change it. i think that reasoning comes from the fact that transmission fluid has a lot of detergents in it, and that after 100k a transmission has a lot of sludge in it. the new fluid stirs it all up and puts it back into motion where it quickly clogs up the new filter and kills the tranny. thats why i think its good to change it twice within a couple of weeks. also be aware that a pan/filter drop only drains about 1/2 of the fluid. the cooler, valve body, and torque converter retain a substantial amount of old fluid, as much as 4 or 5 or more quarts.

 

Devils advocate... have your Dodge dealer do a tranny flush with their cleaners... here in NY, they often use BG. After the cleaning, have them drop the pan and put in a new filter. Or perhaps take them a new deep disk pan with a drain plug.

For what it is worth, I usually buy higher milage cars/trucks and always have the engine and tranny flushed. It has not been a problem yet.