I have a 1994 F250 460/7.5L with 109,000 miles on it and I was wondering if a transmission flush would be worth it. There doesn't seem to be any issues while shifting, but I've been told that it would be a good idea. Doing it myself is only going to save me about $30, the mechanic I called would charge me $200.

 

An actual flush, or just a complete fluid change?

Lots of transmissions have been working okay, then got flushed with one of those power flush system and then started slipping because the power flush blew out internal seals and washed away friction material from the clutches.

So, IMO, a complete fluid change is okay, a flush job isn't.

 

Have you ever seen a power flush machine? I haven't. How would that work?

What I am suggesting is that you've been reading internet urban legends. Power flushing doesn't exist, and what you say happens doesn't happen.

 

You mean this machine: https://www.bgprod.com/catalog/trans...change-system/ doesn't really exist?

 

How do they clean the magnet and change the filter without dropping the pan? They don't.

I could have gotton my ATF and filter changed much cheaper than what it cost me to just go to local trans shop. I used a better quality ATF, Motorcraft filter and Marks procedure. I just prefer to do it myself so I know it is done right.

 

It does exist..but its just a fluid exchange machine like the others.

A complete fluid change and a "flush job" is the same thing.

The word "Power Flush" is misleading, the machine not going to force fluid throughout the the transmission with great pressure and clean all the parts like a pressure washer or anything like the scrubbing bubbles commercials. The machine just adds new fluid headed back to the transmission from the cooler and captures what the transmission pump is pumping to the cooler until you reach a "complete fluid change". Mixing of the the new and old fluid will occur in the transmission and you never get all of it out, well maybe after 30 qts you will be pretty close, but what about the magnet and filter?.

Manufactures play on words to get your attention, like "Contaminated transmission fluid leaves behind deposits that can cause gear grinding, delayed transmission response, or stalling"... Fluid deposits that can cause gear grinding? Automatics don't grind gears, not unless they are broken and changing the fluid don't fix broken.

Here they say " removes old automatic transmission fluid while simultaneously adding new fluid ", this is the fluid exchange.

Then they say something stupid like " The simultaneous exchange method permits no intermixing of new and old fluids, meaning the new fluid will last significantly longer. ", downright lie, it just can't happen. The not knowing consumer eats this stuff up its all a sales pitch. Fluid flushes are a consumer driven service IMO, I think its a waste of money and fluid, but I will do it if they want too.

 

Yes, it exists, but it doesn't do what you think it does. It exchanges the fluid, it does not "power flush" the system. If you understood how an automatic transmission works, and how this machine ties into the system you would understand that all it can do is exchange new fluid for old fluid. It cannot introduce high pressure fluid into the transmission. There is no way to do it.

 

Then what do you recommend?

 

I am sure my view is different than most people on this mainly because I see failures everyday that could not have been prevented by fluid changes and I was including all makes and models with that statement, so I should have been more clear on that. I will admit that there are transmissions that benefit more from frequent fluid changes and the Ford rear wheel drive is one of them, not so much the front wheel drive though.

I like just the regular pan drop and refill on a regular bases in most cases, there are cases where I will go for the flush but it depends on the vehicle and the condition of the tranny. Usually I can get a good idea of a problem after dropping the pan. It just seems like a waste of fluid when you have to pump 20 qts through a 12 qrt system until it looks clean.