Torque converter lock-up ?

[EddieS'04]

Is it normal for our transmission to go into torque converter lockup, when cruising at a steady 35-37mph? The OD comes in at 42mph. I have never noticed till as of late that the converter, lockup before OD comes in. Other Fords I have had, the converter locked after OD came in.

The trans is stable and shifting correctly. NO light of death. Just my curiosity.



Thanks, Eddie

 

[Todd Z]

Ed,

Actually on the ST the converter does lock up in each gear at different times...



Wounder where the extra heat and wear in our trannys comes from...LOL :lol::lol:



Todd Z

 

[EddieS'04]

Thanks Todd. Yup you would think the trans would run cooler if the converter stops slippage at lower speeds.

 

[Bob Myers]

 

[Bob Myers]

My question is, why when I am towing a 4000# TT behind my 07 STrac V8, does the tranny hunt back and forth in top gear and what can I do about it. It cuts my gas mileage to 10MPG at 65 +? I tried running in 3rd and with OD off, but that drops the mileage even more. If I could lock out the converter I think I could make 12 MPG towing. BTW I get 20 solo hyway and 15-16 local mpg.

I think a higher rear axle ratio would help, stock being a 3.55.

Bob

 

[Todd Z]

bob, you have a 6 speed transmission in that truck..... Just try the OD off and see, unfortunately the converter will still lock up...



The only way to help you is to purchase a computer programmer and re flash your computer with a towing tune...



Todd Z