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Discussion Starter #1
So this morning I was scheduling my transmission service at my local shop (I no longer do my own work) and in the discussion we had to talk about flushing only vs proper fluid and filter change. He was surprised I insisted on the filter, too, noting that most customers opt for the flush only.

I've always been a drop the pan and change the filter guy...just like the manual says. But I'm curious now... How many of you opt for the flush only versus dropping the pan and changing the filter? And if you are in the flush only camp...why do you feel that way?
 

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Around me the flush is about 3- 400 cheaper at the stealership ... They simply don't want to just drop the pan and have to reseal it ... Honestly I would love to do the pan drop and replace the filter and flush it but at almost $700 beans I will do the flush for now
 

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Discussion Starter #3
Around me the flush is about 3- 400 cheaper at the stealership ... They simply don't want to just drop the pan and have to reseal it ... Honestly I would love to do the pan drop and replace the filter and flush it but at almost $700 beans I will do the flush for now
Where do you live? I'm looking at less than $300 for the filter and fluid. Local shop, not the dealer.
 

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Ny - yea that was the stealership ... The filter is all of like $40 bucks .. the location just doesn't want to break the pan seal and clean it up and reseal it I think . But at this point I've only got 30k something on the truck and it's all reg highway and driving miles .. so the flush would be fine . The flush will get over 2/3rds of the fluid out because it does flush most of the torque converter where as a pan drop you may only get 1/3 or so of it out ....
 

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I always like to drop the pan and change the filter but I’m buying junk with well over 100k and at that mileage it’s kinda a bad idea to flush it if it’s never been done . I usualy put a drain plug in the pan so I can drain it a few times after the filter change and get some relatively new fluid in there . You go threw a case of fluid but still costs much less than the dealer


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I always like to drop the pan and change the filter but I’m buying junk with well over 100k and at that mileage it’s kinda a bad idea to flush it if it’s never been done . I usualy put a drain plug in the pan so I can drain it a few times after the filter change and get some relatively new fluid in there . You go threw a case of fluid but still costs much less than the dealer


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Wrong. Changing the fluid and filter will never hurt.

The myth comes from people with hit trans, well clutches.
 

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Wrong. Changing the fluid and filter will never hurt.

The myth comes from people with hit trans, well clutches.
Like I said drop the pan and change oil and filter but the widespread consensus is don’t FLUSH a high mileage tranny that hasn’t been done regularly


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Discussion Starter #8
Right now I'm at 113k miles and my fluid pretty much looks as clean as the day it rolled off the show floor. Owner's manual says to change fluid & filter at 100k so I'm a bit late, but better late than never. I drive a lot of highway miles, so my tranny has a pretty easy life. I do want my truck to last a long time.
 

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Like I said drop the pan and change oil and filter but the widespread consensus is don’t FLUSH a high mileage tranny that hasn’t been done regularly


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I did say that like a douche. I’m sorry.
 

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The danger is in changing the fluid at all, regardless of flush or filter change. I have made high mileage transmissions inoperable by changing the filter and fluid.
 

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Discussion Starter #14 (Edited)
I did take it to my local shop today and got the transmission fluid and filter change as well as the diffs and transfer case. Was not cheap...especially after they discovered the plug on the front diff was seized. But my truck should be good to go for a long time now!
 

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The danger is in changing the fluid at all, regardless of flush or filter change. I have made high mileage transmissions inoperable by changing the filter and fluid.
This usually only will happen, when the filter is installed incorrectly, or the wrong filter is installed, or the incorrect fluid is used.
 

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This usually only will happen, when the filter is installed incorrectly, or the wrong filter is installed, or the incorrect fluid is used.
It is literally impossible to bolt the pan up to the wrong filter. You will break the m8 bolts before you pull the up or break the neck.

Once again it’s a common misconception of a slipping trans and high mileage one.

If you have a problem, changing the fuild will hurt. Because all the clutch’s and steels are in the fluid. Once dropping it, there’s no friction to grab.

R&R or change the fluid before it messs up.
 

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It is literally impossible to bolt the pan up to the wrong filter. You will break the m8 bolts before you pull the up or break the neck.

Once again it’s a common misconception of a slipping trans and high mileage one.

If you have a problem, changing the fuild will hurt. Because all the clutch’s and steels are in the fluid. Once dropping it, there’s no friction to grab.

R&R or change the fluid before it messs up.
I have witnessed incorrect filters installed.

Yes, if the trans is slipping changing the fluid will not help. The fact there is metal and clutch frictions in the oil, the real reason the unit may not move again is because the pump has been trashed. With the oil drained an the filter removed the pump drains out. The worn out pump will not prime.

Yes, R&R the fluid before it messes up.
 

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Or if the original filter oring gets stuck in the trans and the tech doesnt notice it, you can stack the two orings and cause a issue.

The danger is in changing the fluid at all, regardless of flush or filter change. I have made high mileage transmissions inoperable by changing the filter and fluid.
You must have really screwed something up then.
 

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Discussion Starter #20
It kind of seems to me my transmission is shifting a bit smoother since the fluid and filter change. Now...it was working quite well before the service...but I've been driving it almost a week now since and it just seems a bit smoother somehow. So...is this just my imagination or could fresh fluid and a new filter smooth things up in a noticeable way?
 
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