Dbl Down Shift 6R80

[oldbones]

When flooring my Mustang from a roll, the car is doing a double down shift from 60+mph. I can't figure out how to get rid of the issue. I'd like the car to shift into 4th or 3rd from 6th gear and skip 5th. I've attached the tune, an image snip of the issue and the data log for reference.

Turbo78.5_Transmission.hpt

6pull_TransmissionTestTune2.hpl

Screenshot 2023-11-17 131444.jpg

[murfie]

From 6th the options are 5th, 4th, or 2nd. Above 60+ 2nd is probably not an option due to the RPM limit. So the only options are 5th or 4th and A 6th directly to 3rd is not possible. This is because these gears share a common clutch in their function and there is just a single pair of on coming and off going clutches. 6th and 3rd share no common clutch. Neither do 5th and 2nd nor 5th/6th and 1st. All of these would require what you call a double shift.

In this log it goes 6>5>3 skipping 4th.

Raise the 57mph and 59 mph to make it do a 6-2. You'll need to raise the raise the RPM limits if you desire.
Lower the 88's to less than the desired roll MPH to make it do a 6-4 instead of tring for a 6-3.

4th or 2nd.png

If you want a one down shift to 3rd it would need to be rolling in 5th or 4th at the MPH and low pedal input, I suggest making it do a 6-5 at a lower pedal input at 60+. Theres many cells available to fill out to accomplish that and not disturb highway cruising. 35-49mph shouldn't be the only place it does 6-5 before 5-4.
as an example, just flip the ADC and MPH for the normal table. Dont make it go into 5th, if you are starting at a MPH that will command 2nd, it will need a double shift to go from 5th to 2nd.

6-5 DS.png

[oldbones]

Thank you for assisting with this, I'll make the adjustments and test soon. Where would you recommend that I read up on the design functions of the 6r80 or the 10r80--I'd like to learn more. I'm specially interested in learning the mechanical pathways through the transmission, such as if B clutch is applied with E clutch, 5th gear, is the power moving through the forward planetary?

[murfie]

Information like that can be found in the transmission service manuals.

6R80 5th gear.png

3rd- 4th 6R80.jpg

-The forward clutch (A) connects the front planetary carrier to the rear No. 3 sun gear. This provides a gear reduction ratio of 1.52:1
from the input shaft to rear sun gear No. 3. Gears 1,2,3,4.

-The direct clutch (B) connects the front planetary carrier to the rear No. 2 sun gear. This provides a gear reduction ratio of 1.52:1
from the input shaft to rear sun gear No. 2. Gears 3 ,5.

-The intermediate clutch (C) holds the rear planetary No. 2 sun gear stationary to the transmission case. Gears 2, 6.

-The low/reverse clutch (D) holds the rear planetary carrier stationary to the transmission case. P, R, N, and Low speeds in 1st.

-The overdrive clutch (E) connects the input shaft with the rear planetary carrier. Gears 4, 5, 6.