Transmission Flush - Is this a scam?

[ChallengerHK]

I had my oil changed today, and the trans fluid was pretty brown. No real surprise there. Then they told me that a) the car can only use synthetic trans fluid, and that b) because of "A" it would be $235 to do a flush.

I have a hard time buying into a $235 trans fluid change. Is this a scam?

[moparmaniac59]

Are we talking a Torqueflite 727 for an old Mopar or for a new Mopar?? Even if it's a new Challenger, that sounds VERY expensive. I'd drain it and replace the fluid/filter myself unless it has other issues. Just my 

                                           Matt B.

[Bullitt-]

I'd say the $235 is a scam for any common vehicle.. If it's the 727 you do not need or even want synthetic... you can completely drain it yourself, buy the fluid & filter for around  $35.00, I'd guess a shop around here might get a C-note

[72rtchallenger]

I'd say the $235 is a scam for any common vehicle.. If it's the 727 you do not need or even want synthetic... you can completely drain it yourself, buy the fluid & filter for around  $35.00, I'd guess a shop around here might be a C-note

 

[moparmaniac59]

I use type "F" in my 727. It's not synthetic. 


                                               Matt B.

[ChallengerHK]

Sorry, wasn't thinking about what I wrote. And I'm supposedly a writer 

This is for my Hyundai, 04 Elantra.

[Bullitt-]

Well it takes a $10. spin on filter so pumping out the old may be the only option... Terry will be along I'm sure bit it appears that there may be a need for "SP-III transmission fluid" from the dealer.   or http://www.amazon.com/s/ref=nb_sb_noss?url=search-alias%3Dautomotive&field-keywords=Automatic+Transmission+Fluid+SP3&x=11&y=20

[shadango]

My dad-in-law had his 98 Dakota's trannyflushed by the dealer (this is like 4 years ago)...no tranny issues going in.....major ones coming out.

I wont ever do a flush unless I know I have other issues and its a last ditch measure.

[Cooter]

If you've never worked on any of the late modle trans', you would not understand why it is so much $$.....

For one thing, everybody including our shop uses synthetic as it meets or exceeds the man. spec for todays cars...Yes, flushing your trans will make it last longer..Think about it, you change the oil every 3000 Miles, why would you run your trans for over 100K miles? it breaks down just like engine oil, sometimes even more cause of the heat...Yes, you Could change your own trans fluid, but are you really getting all the old fluid out? At most shops that offer "Flushes" the machine is a one to one meaning one old quart out, equals one new quart in....That machine alone from BG cost over $5K....The ones we NEVER try and sell a flush on are the ones that the cust. has driven it until it won't go any further, and now wants it flushed to see if it will "Help" it along...By the time the damage is done, it's too late. This is why you are told before that you need to flush your trans....

[shadango]

But are you REALLY flushing ALL of the old tranny fluid out?   

Seems to me as you pump new fluid in, it would mix with the old.

Plus, dont must flushes do a back-flush method?   Seems like that could break loose any particles etc that may have built up and end up places you dont want them.   

[ChallengerHK]

I'm more or less agreeing with this. I might not get 100% of the effect from doing a drain and fill...but I'll bet I'd get 80% or more of the effect at around 25% of what they want to charge.

[Cooter]

But are you REALLY flushing ALL of the old tranny fluid out?   

Seems to me as you pump new fluid in, it would mix with the old.

Plus, dont must flushes do a back-flush method?   Seems like that could break loose any particles etc that may have built up and end up places you dont want them.   

1. Yes, it's a 1 to 1 machine..It goes into what's known as "Bypass" mode and just runs as the car would normally right through the machine....All of the fluid is still being filtered through the trans' filter...

2. No, the old fluid goes into a different chamber in a "Bladder" type set up inside the machine and the old actually pushes the fresh fluid into the car from the top side of the "bladder"...

3. No, most machines hook up and only work by the trans' pumping action. The machine By BG does not use it's own pump..

I'm not trying to convince anyone here to flush their trans, as some will always feel they are being scammed by any service that's recomended. All I'm saying is there is a reason WHY it's done and why it's so expensive when doing Full synthetic flushes...The fluid alone will run the cust. around $90.00 for around 4 gal...

[shadango]

Just to be clear, I am not calling it a scam or not.....

I really do want to know how it works....

To me, if the tranny were nothing but thin lines,  I could see how a "1 to 1" exchange would be possible.....the new fluid would come in on one end of the line and then push out the old stuff out the other end. That would be "1 to 1".

But, thats not how the tranny works....you are pumping the fresh fluid into the line, which then pushes into thru the passages....ok so far....but then into the torque convertor and pan, which (I think) would mean that the new fluid would co-mingle with the old stuff....think fish tank.....if you take thin clear tube and pump a red dye into that tube and into a fish tank filled with clear water, the dye slowly turns the water pink as the dye mixes with the clear (fresh) water......the volume of the fish tank would rise and overflow and get darker and darker red as more volume of the dye was pumped into the tank. You are just mixing the dye (fresh fluid) with the water (old fluid).........which is the exact criticism that pro-flush folks say is the problem with doing a drain and fill yourself.

So I guess the question is how do you keep from mixing the new fluid and the old fluid in the pan and torque convertor during a machine flush?     The only way I can see it replacing 100% of the fluid would be to "overflush"....ie send 4 or 5 times the amount of fresh fluid into the tranny to push the majority of the old fluid out and reduce the mix, with the machine somehow analyzing the fluid being recovered and continuing to pump fresh fluid in until the fluid being expelled was also fresh.  That would mean that if a typicaly tranny used 10 quarts of fluid, 40-50-60 (who knows how much) quarts of fresh fluid would have to be expended to reduce that mix to a minimum....that doesnt seem like something that would be cost effective or practical.

What am I missing?

[Aussie Challenger]

Just to be clear, I am not calling it a scam or not.....

I really do want to know how it works....
 The only way I can see it replacing 100% of the fluid would be to "overflush"....ie send 4 or 5 times the amount of fresh fluid into the tranny to push the majority of the old fluid out and reduce the mix, with the machine somehow analyzing the fluid being recovered and continuing to pump fresh fluid in until the fluid being expelled was also fresh.  That would mean that if a typicaly tranny used 10 quarts of fluid, 40-50-60 (who knows how much) quarts of fresh fluid would have to be expended to reduce that mix to a minimum....that doesnt seem like something that would be cost effective or practical.

What am I missing?

That is why flushing can be expensive, in any trans service the convertor fluid usually doesn't get flushed (some places do blow out the convertor). In these modern cars the service is usually done while the engine is running and to try to get most fluid out up to 2X more fluid can be used and because old trans can die due to lack of servicing in the past. As said before they can then develop new problems after flushing and the mechanic has to cover the warranty.
Auto trans fluid is high detergent and the only thing that will kill it is heat so now days manufacturers tend to seal the trans and don't list a service interval, workshops do the flush as a precaution at set intervals if customer agrees.   

[shadango]

That is why flushing can be expensive, in any trans service the convertor fluid usually doesn't get flushed (some places do blow out the convertor). In these modern cars the service is usually done while the engine is running and to try to get most fluid out up to 2X more fluid can be used and because old trans can die due to lack of servicing in the past. As said before they can then develop new problems after flushing and the mechanic has to cover the warranty.
Auto trans fluid is high detergent and the only thing that will kill it is heat so now days manufacturers tend to seal the trans and don't list a service interval, workshops do the flush as a precaution at set intervals if customer agrees.   

I had mentioned my dad-in-law's truck before.....He had kept up on his tranny servicing...dealer did the services.....at around 60k miles (guess) they persuaded him to do the flush.

Tranny died right there.

I cant believ that a tranny with low mileage on it, having had one other fluid change already, would have problems to the point that it would die unless the flush had "something" o do with it.  My 92 Dakota has 120k on it.....the last time the tranny fluid was changed was at around 60k......the fluid still smells and looks new so I aint messing with it.

My durango has had a fluid drain and filter drop at 30k or so and is due for another....no flush in my future.

The fish will get a filter drop and fluid change each year or two, per my tranny rebuilders suggestion.