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What is your maintenance plan for your transmission in the Ecoboost?

MavStangVa

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You'll never replace all of the dirty fluid with partial drains, that is true. But if you drain out 2/3 and refill it, the fluid now has 1/3 of the contaminates that it had before you did the drain. As you said, the contaminates are now diluted, and since 1/3 was left, that's 33% of the contaminates prior to the drain.

If that isn't satisfactory, you could do multiple drain & fills in a row to get it cleaner. If you did 2 drain and fills in a row with short running in-between to mix the fluid, you would have 10.89% of the contaminates left in the fluid that you had when you started. If you did 3, you'd have 3.59%.

100% x .33 = 33% x .33 = 10.89% x.33 = 3.59%
True for oil changes also. Never get 100% of the old out. But enough to greatly reduce the contaminate level. Of course additional contaminates are being added during driving until the next drain and fill. But again it removes enough hopefully to prevent failure. Thanks for the numbers (y)
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Cherokee

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I have always changed trans fluid at 35,000 miles on my vehicles since 1970. Now with 2 Hondas with CVTs and my 23 Mav XLT hybrid I change the trans fluid at 30,000 miles.
I always waited and watched, doing nothing till the fluid starts to turn brown from pink.

One Taco Tranny turned at 15,000 miles of hard commercial use. I installed a 12,000 BTU tranny cooler in line after the radiator and after 70,000 miles it was still pink.
That automatic was running fine at 280,000 miles when I sold it.
On only that one 15,000 miles fluid change…
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Tim d

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Ford will also recommend a new transmission at 6 years at your current mileage. Be smart & sell it at 5 years. But not to me:)
If i have to replace a transmission in 6 years i will never buy another ford again. I have a 17 year old ram that has never had the transmission fluid changed and its fine.
 

Chops

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If i have to replace a transmission in 6 years i will never buy another ford again. I have a 17 year old ram that has never had the transmission fluid changed and its fine.
Like you - I have driven high mileage on several vehicles without ever a transmission drain & fill.

However, two things are different now.
1) I’m retired and have a DIY addiction.
2) Our 8F35 transmissions are kind of crappy - especially with dirty fluid.

You would not be the first to swear off Ford if your 8F35 transmission goes kaput. There is an active thread on the forum now on that very topic btw…
 

DinoLord

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You'll never replace all of the dirty fluid with partial drains, that is true. But if you drain out 2/3 and refill it, the fluid now has 1/3 of the contaminates that it had before you did the drain. As you said, the contaminates are now diluted, and since 1/3 was left, that's 33% of the contaminates prior to the drain.

If that isn't satisfactory, you could do multiple drain & fills in a row to get it cleaner. If you did 2 drain and fills in a row with short running in-between to mix the fluid, you would have 10.89% of the contaminates left in the fluid that you had when you started. If you did 3, you'd have 3.59%.

100% x .33 = 33% x .33 = 10.89% x.33 = 3.59%
Your math is flipped unless you know of a way to drain a lot more fluid than comes out of the drain plug.
 

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Tbone289

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Your math is flipped unless you know of a way to drain a lot more fluid than comes out of the drain plug.
I was using 2/3 provided by the message I was quoting. There is nothing flipped if you use the correct context.
 

Tbone289

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I guess their math is flipped, too.
Substitute in whatever percentage you like into the math. It shouldn't difficult for you if think hard and hold your mouth just right.
 

Tim d

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Like you - I have driven high mileage on several vehicles without ever a transmission drain & fill.

However, two things are different now.
1) I’m retired and have a DIY addiction.
2) Our 8F35 transmissions are kind of crappy - especially with dirty fluid.

You would not be the first to swear off Ford if your 8F35 transmission goes kaput. There is an active thread on the forum now on that very topic btw…
Iam an old fart. 66. I have a 72 cuda i have owned for 35 years. Just replaced the tires this summer that were 30 years old, and i have never replaced the brake fluid in those 35 years. To me, some of this maintenance stuff people do is pure overkill. Thats just me though.iam hoping to get 15-20 trouble free years out of our mav going by the fords recommendation. They should know best or they would be out of business.
 
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DinoLord

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Iam an old fart. 66. I have a 72 cuda i have owned for 35 years. Just replaced the tires this summer that were 30 years old, and i have never replaced the brake fluid in those 35 years. To me, some of this maintenance stuff people do is pure overkill. Thats just me though.iam hoping to get 15-20 trouble free years out of our mav going by the fords recommendation. They should know best or they would be out of business.
One, you obviously haven't driven it much.
Two, DOT4 and up absorbs moisture at a much faster rate than DOT3 did.
 

mwelby

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If i have to replace a transmission in 6 years i will never buy another ford again. I have a 17 year old ram that has never had the transmission fluid changed and its fine.
Interesting….how many miles?
 

Tim d

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One, you obviously haven't driven it much.
Two, DOT4 and up absorbs moisture at a much faster rate than DOT3 did.
No those tires prolly had less than 15 k on them.and yes i know the newer brake fluid is inferior.
 
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DC1990

DC1990

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Well this got interesting quick 😆

I plan on keeping my Maverick for at least 10-15 years. So I guess I'm in a bit of a different situation than most who trade up every few years or until their extended warranty runs out. I know I will have my truck outside the warranty so I just want to do the best I can to prevent problems.
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