Transmission Drain and Fill vs Flush

I had the truck check by a mechanic and he said it shifts fine, but recommend to do a fluid change to pro-long it. So I had them drain n fill with a filter changed... 5 Qts of transmission fluid and with tax cost me $202. I didn't think it was a bd deal. Took them about 1.5 hr to get it done while i waited. It shifts good... I want to drive the truck for another 10 yrs.

 

Totally agree with gearcruncher. I decided to go ahead and drop the pan and replace the filter on my drain and fill. There definitely was a dirtier deposit of fluid and sludge in the bottom of the pan (Transmission fluid changed about 40k ago but I don't know if they dropped the pan). Also I was quite suprised there was almost an extra quart of fluid in the bottom of the pan that didn't come out the drain plug.

 

There’s a lot of discussion on this topic in other forums I attend (Porsche, BMW) concerning possible “consequences” of transmission flushes for vehicles above ~70k miles. There maybe some quantity of sediment, however small that might be placed into the fluid stream by flushes whose velocity exceed typical running fluid velocities. In general, as vehicles age, flushes are less than advised. Use the fluid drain/fill (or repeat drain/fill) procedures advised in this forum.

 

Posted this in a different thread but the dealer performed a flush (first transmission service at 126k) after I specifically stated on the phone that I did not want a flush but a drain and fill. After talking to the scheduler I spoke with an advisor who told me as far as he knew they have never performed a flush while he has been there.

I can’t imagine there’s anything I can do but go on with things and hope for the best?

 

I did a full flush on my 2010 at 125k and everything was fine. I did have to replace the transmission at 126k though.

Just kidding! Currently at 155k and has never shifted better than after the full flush at 125k. I did drop the pan and clean up the magnets and change the filter as well.

 

At what mileage do you think you’ll service the transmission again and will it be a flush or refill?

 

So as I understand the BG trans fluid machine hooks to the tranny cooler lines and replaces the fluid using the pump in the trans. The fluid moves through the trans same as normal. Why would that cause the shit in the pan to become turbulent when the fluid is moving the same as normal operation?
Do these shops not use this machine?

 

Well that’s better news, my dealership papers do state a BG machine was used.

 

Some of the smaller dealers may not have the latest and greatest equipment.

 

Well played! My heart skipped a beat for a second there.

 

Ive been thinking about doing a drain and fill on my 2.7 auto and the dipstick says "No need to replace ATF fluid under normal driving conditions". Thoughts on this?

 

Why not drain and fill.....keeps the transmission fluid fresh! The service manuals I've read suggest changing the transmission fluid....drain and refill. Like others have commented... An ounce of prevention is worth a pound of cure. A little precaution before a crisis occurs is preferable to a lot of fixing up afterwards! I think we can all agree to this....
Go Team TW

 

Yea I agree with you. Ive been doing drain and fills every time I change diff/transfer case oil. Just curious to get some input on this "lifetime fluid". I cant see any oil not braking down over time.

 

Some of the misconception is the transmission fluid isn't used for lubrication solely, its used more for hydraulics in the transmission. The transmission fluid will be more susceptible to heat if towing a trailer ect. Equally important will be to monitor the temperature to the transmission oil to get the longevity as stated "lifetime Fluid". My first Tacoma was a first gen with 375000 Km when sold and is still running thanks to regular maintenance on all fluids and oils ect.
I think the fact its not uncommon to see Tacomas in great condition with high mileage speaks to the adage ....An ounce of prevention is worth a pound of cure. A little precaution before a crisis occurs is preferable to a lot of fixing up afterwards
Great to hear all the comments...go team TW!

 

When your old fluid was new , your fluid worked hard to keep your transmission running clean every time you drove your truck by placing minute particles on the bottom of the pan .
Your old fluid is depleted or on its way to depletion .
Even if its still slightly red or light brown , you can bet the re-agents in your fluid have broken down and are no longer as efficient as new fluid
New transmission fluid has a very very high detergent content . Works great if you spray the stuff on rusty bolts .
When you introduce the new fluid into a transmission with old fluid , the fresh detergent dislodges the particles that were settled on the bottom of the pan by your old fluid . Keep in mind that the bottom of the transmission pan is the septic tank of your transmission . Our trucks have an aluminum valve body combined with aluminum valving . Aluminum is soft . Steel penetrates aluminum . When the steel penetrates aluminum valving , you no longer upshift
This is only one reason I remove the pan on every transmission service I perform . There are many more reasons to remove the pan before flushing

 

call and ask them what machine they use

Good explanation.
I wasn't saying removing the pan isn't necessary. It is, and the filter should be changed. It's a lot of peoples thought that the machine and the actual flush is the reason they could have problems.
The BG machine I referenced uses the trans pump. the fluid goes in as the old comes out. There is no more "washing" or "flushing" than what is going on every time the vehicle is driven.

 

So if I'm reading correctly, it sounds like even though the 2nd gen V6 auto transmission is "sealed" with a "lifetime" fluid, it's best practice to go ahead and do a drain & fill at 60k miles? The only time you'd need to drop the pan & do a full flush is on an older tranny that's never been serviced.

Is that correct?

 

Not correct in my books but I do this for a living.
Always take the pan off and determine the contamination level before flushing
If the magnets , filter and bottom of pan are squeaky clean , proceed to a flush
IF the contamination is high , put the pan back on and refill .
You can drain the converter by disconnecting the return cooling line and allow the converter to gravity drain rather than flushing.
Toyota's 60K mileage guideline is generic . You are the owner of your truck and you know how you treat your truck . Its up to you to determine the service intervals

 

Now that I’ve done a full flush and replaced the filter, I’ll just do a simple drain and fill with fluid level check annually. I already have done one annual D&F and the fluid looked quite red, so I was happy. Maybe another full flush when I’m at 200,000 miles

 

@gearcruncher Really appreciate reading a professional's opinion, so much disinfo online. Is it advisable to disconnect the trans cooling line and run the engine to pump out more of the old fluid, as some are doing? Or is there too much risk of damaging the trans that way?

Thanks