Hi all,
Just to let all the people know who have a vehicle with 6F15 or 6F35, I've just changed the transmission fluid on mine, which is a 6F15 2017 and 22500 miles and it was quite dark.
I was getting "clunky" changes and a bit of delay, seems much better now.
I don't know whether you want to turn this into a general sticky on all the boards to advise people.
 

6F15 is fitted to 2015 on Focus and EcoSport and 2017 on Fiesta (Mk8)
It took 5 litres

And, just to add to this, I found, from speaking to someone with an issue on the Forscan Forums, that the transmission type was not configured in central configuration.

It was set to "not specified/unknown"

As my transmission is not listed as an option (6F15) and, as the guy on Forscan told me, 6 speed automated FWD is, I selected and installed that config.

Wow, what a difference, nearly all the 2nd gear slipping has gone and it changes gears much smoother now.

I also noticed that my final drive ratio is not configured (3.44:1) so I think I'm going to configure that now.

Hmmmmm my 4 speed can occasionally be a bit clunky, grabby, moreso from 2nd to 1st, will give my box a sniff LOL

Just gone past 39000

46 minutes ago, Jimpster said:

Hmmmmm my 4 speed can occasionally be a bit clunky, grabby, moreso from 2nd to 1st, will give my box a sniff LOL

Just gone past 39000

Yep, change the fluid, it will help

On 7/25/2022 at 11:20 AM, DaveT70 said:

And, just to add to this, I found, from speaking to someone with an issue on the Forscan Forums, that the transmission type was not configured in central configuration.

It was set to "not specified/unknown"

As my transmission is not listed as an option (6F15) and, as the guy on Forscan told me, 6 speed automated FWD is, I selected and installed that config.

Wow, what a difference, nearly all the 2nd gear slipping has gone and it changes gears much smoother now.

I also noticed that my final drive ratio is not configured (3.44:1) so I think I'm going to configure that now.

Do you remember under which module you did this?

i want to try the same on my wife’s ‘18 Fiesta. 
she has the same 2nd gear splippage and because of this the urban fuel consumption is high. 
 

42 minutes ago, DanTudor said:

Do you remember under which module you did this?

i want to try the same on my wife’s ‘18 Fiesta. 
she has the same 2nd gear splippage and because of this the urban fuel consumption is high. 
 

Fiesta normally performs better than Focus due to the much better MAP.

A little bit of slip is normal, as long as it locks up eventually

Try resetting adaptive shift learning first and do a complete re-learn drive and see if that improves it.

Check the fluid level and, if you are over 40,000 miles, change the fluid

My Son & Daughter both have MK8 1.0 with 6F15 and they both perform miles better than the Focus & EcoSport with 1.0 (125) 6F15

hello everyone, does anyone have the problem with the ford fiesta 6f15 automatic transmission that the error code: p1783 which means: automatic transmission oil overheated I hope you can help me further

Change the fluid first and see if it goes away, if it's very brown then run for 500 miles and change the fluid again as only 50% drains out

Hi everyone,

I want to change the transmission fluid on my car. It has the same 6F15 transmission.

The issue is that when the weather is cold, the gears start to slip a little — but after about 15 minutes of driving, everything goes back to normal.

I’m thinking about changing the fluid, but I’m a bit scared because my car has 124,000 miles on it.

Can someone please give me some advice? ❤️❤️

On 9/9/2024 at 10:41 AM, DaveT70 said:

Change the fluid first and see if it goes away, if it's very brown then run for 500 miles and change the fluid again as only 50% drains out

What advice do you want?

Whether to change it? - YES!

Or how to change it?