Transmission Flush
 

I know that the book suggests flushing the tranny (48re) at 30,000 miles. My dealership said that they dont change the filter until trouble occurs. What are all of your thoughts.

Its cheap insurance to change the filter along with a flush and fill. Dealer probably wants to change the filter when problems occur so they can sell you a new tranny. Just my .02

Change filter and fluid. Waste of money to do a flush. My brother-in-law owns a tranny shop.

Been in the repair buis. for over 25 yrs , but not a trany shop , but used a few for my costumers , and used industry magazines to keep keep up on things .
What I do to my truck is , pull the pan & filter , because this way I can see whats in the pan to help give an idea of the condition of the trans. , by the time the fluid needs changing [ 20,000-30,000 depending on how you work the trans. ] the gasket may be leaking a little anyway , then flush the trans. to change all the fluid , about 16 qts ves. 4 qts .

I'm by no means a tranny expert, but there have been numerous threads where people emphatically say NOT to flush!

Maybe a tranny pro will chime in.

had mine flushed at 30,000 miles- just had it done two weeks ago at 60,000 miles and had the filter changed. having the system flushed is cheap insurance if you ask me. my dealer charges my 200 bucks to flush the system every 30,000 miles. i prefer doing it this way as opposed to a drain and refill a couple of times a year!

I believe the theory is that any dirt, particles, etc. that might be "stuck" in a small crevice can/will be dislodged during a flush whereas if they were left alone they would stay put and not cause any damage.

I don't have enough knowledge of automatic trannies or flushing to have an opinion one way or another...:cool:

Tell you what, I just had my tranny serviced with a flush/fill/filter, and the difference of before and after is amazing. Feels like a whole new truck again, and it cost 100 bucks, if anyone is quoting you more than that well then it definitely is a waste because they saw you comin' from a mile away.

Make sure they change your filter either way. The tranny Guru I know says no to flushes as a general rule. LanceK is correct.

I ask my mechanic friend (over 30 years experience) about flushing the trans when mine hit the 30K mark and he was not really a big fan of flushing either,he mentioned something about possibly dislodging junk too. He said if the fluid looked really burn't looking that he would consider it otherwise just drop the pan. That's what I did and will probably do that again at 60K.

Tony

There are two methods of flushing the tranny. One uses pressurized system that forces the fluid to your tranny, and the other method uses tranny pressure to slowly force the old fluid out while the new fluid is added. Now, the first method is a no no, as it causes all kind of junk to get dislodged and float in the tranny. Second method is safer, as no extra pressure beyond tranny pressure is exerted on the system, but the results will differ based on the age of the tranny. The higher the millage, the higher possibility for the failure.
ATF is a very strong solvent, and because of this, general practice is to drop the pan, replace the filter and add the difference in ATV. This will introduce enough new fluid to offer protection, but not enough to loosen all the junk.

Anywho, whatever method you choose, alway, and I say always drop the pan and replace th filter.

Also inline magnetic tranny filter is a good idea, as pan filters are not that effective similar, but not exclusive to this:

http://www.emergingent.com/subpage1Magnefine.htm

[roll]

The reason I was told for not flushing the tranny is that most people ignore any service to their tranny until they hit close to 100K. Then they suddenly get concerned about the life of the tranny and want it flushed. At that point the fluid has varnished on some of the parts and a flush can/will dislodge this junk. Then tons of problems. Then the customer says"well it worked fine until you flushed it!" Now, I'm going to have mine flushed every 30K since I plan on owning this thing until I retire. My gasser had over 150K with no trans problems doing this, so I expect many miles out of this truck.

Thanks For All Of Your Insights
Thanks
Adam

I had my trans filter changed out Wednesday and it took 6.5 qt’s of fluid to refill it and not the 4 or 5 qt’s some say it takes. I can say just adding high quality synthetic trans fluid made a big difference in how it shifted and I only have 14,500 miles on the truck. BTW, I did not let them adjust the bands to make it shift better as don’t believe in the bands being adjusted until the trans starts to slip.

I don't believe in flushes either. Back in 2002, my wifes 2002 durango r/t had a flush at 15k miles and shortly after it started shifting funny and was not smooth at take off so I dropped the pan adjusted the bands and replaced filter. I haven't had another problem since and we have over 60k on it today.

On the other hand, I have dropped pan, adjusted bands and replaced the filter at 10k, 20k, 40k, 60k, and recently 90k miles on my 04 2500 and it still shifts like new. I changed it more often at first to get break in material out.

I am a firm believer of dropping pan over flushes.

Also, in my experience it takes around 7 quarts dropping pan not 4. This is the same in my wifes and mine.