Tranny Fluid Flush?

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EddieC

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Our regular repair shop says they have a machine that flushes out all 12 quarts of transmission fluid and back flushes filter, so I assume the filter does not get replaced. Other than that I don't know the details of the device or the procedure.

He claims that it gets all the fluid as opposed to just the 5 quarts or so in the pan. I can appreciate that but not so sure on not replacing the filter.

I've considered dropping the pan myself but there is too much trepidation about making a mess in the driveway so that's the reason for having it done by someone.

I would appreciate any opinions on that procedure.
 
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Bill 1960

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No. That’s my opinion.

A new filter and new fluid is the way to go, and any tech or DIY mechanic worthy of the name knows how to purge the remaining old fluid out the cooling lines.

Flush machines are a solution in search of a problem. Or more accurately, potentially creating problems.
 

wsteele

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I agree with Bill, not because I have any particular experience on the matter, but just from the advice the guy who installed my replacement transmission gave me. This guy does nothing but transmissions, transfer cases and diffs, all day every day and he was no kid. He sees very old transmissions and pretty much anything out of warranty.

His advice was never use a pressure flush machine to change your transmission fluid. Drop the pan, change the filter and replace the fluid that was lost when you dropped the pan.

He recommended the interval to be 30K, but I think because he thought I was still towing a lot with a pretty heavy trailer. I believe his advice would have been 50K intervals with my current duty cycle, very little light towing only.
 
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EddieC

EddieC

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My owners manual specs the change at 100,000 miles and we are coming up on that. There are no noticeable issues in the tranny function.
 

wsteele

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My owners manual specs the change at 100,000 miles and we are coming up on that. There are no noticeable issues in the tranny function.
My owners manual says 50K for severe service and when you read what they call severe service, it is pretty much everybody. :)
 

OR VietVet

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Like @Bill 1960, @wsteele and @Joseph Garcia have said, don't look for a problem that isn't there and by all means. follow the severe duty schedule. It is virtually impossible to qualify for the "Regular Maintenance Schedule". If someone offers to flush a trans and you are tempted, only allow the machine that uses the transmission pump to move the fluid out and new fluid in. Not the machine that that actually forces the fluid out. I do my transmission maintenance at 20k intervals. Gets the new fluid in there quicker to mix with old and if I towed a lot I would cut that interval in half, but that is just me.
 
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EddieC

EddieC

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There are no noticeable issues in the tranny function, until there are. And then, it is usually too late.
I can only assume that they know their build specs and related requirements.
Our truck has an easy life hauling a dog or two around.
Now if only they had recommendations on front hubs and ball joints and didn't bundle the pieces together....$$$.

It would be nice if there was a replacement tranny pan with a drain plug to avoid taking an oil bath when dropping the pan.
 

OR VietVet

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I can only assume that they know their build specs and related requirements.
Our truck has an easy life hauling a dog or two around.
Now if only they had recommendations on front hubs and ball joints and didn't bundle the pieces together....$$$.

It would be nice if there was a replacement tranny pan with a drain plug to avoid taking an oil bath when dropping the pan.

Many options at Summit Racing, from steel to aluminum.
 

Foggy

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Drop the pan. Clean all components. Replace the Filter. Reassemble and fill with
dex VI fluid... DONE.... Do it every 25K unless you tow alot.. then more often..

Don't make it more difficult than that
 

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