A4LD Mystery (Converter lockup summer only)

[gosub283]

Hi All,

At 50 mph my A4LD torque converter locks just fine in Overdrive. IN THE SUMMER !!
Every winter when the temperatures drop below 34F the TC Lockup no longer works, and stays like that for the whole winter.
Then, this week, when temperatures are in the 40's it starts working again. (In Canada)
This has repeated for 2 years.

Is there a temperature sensor in the auto transmission system that controls torque converter lockup? (Maybe faulty)
And is it accessible or located outside the transmission?
I would like the TC Lockup to work in winter also.

(1994 V6 4.0L XLT 4X4 with A4Ld auto transmission)

Cheers

 

[97RangerXLT]

my guess would be that you have a connection to the solenoid that is not doing well in the cold weather. my guess is that it is probably easy to get to as warming up the transmission/ internal temps are not affecting it, so probably a connection out in the weather under the truck. unplug it, clean the contacts, see what happens.

AJ

 

[901wd#2]

Most tc’s stay unlocked until operating temp is reached. Have you tried blocking your radiator in the winter?

 

[gosub283]

901wd#2,

Yes, it makes sense that there is a temperature control somewhere in the system.
Do you know if the control is located inside the trans? or under the hood somewhere?

By the way, this system does have a sizable transmission cooler, so I bet you are right about blocking the rad cooling in winter.