1994 f350 7.3 idi. First problem is the lockup issue that I see with alot of e4od trannys.

At a steady speed I am able to feel the Trans locking in and out. Will that cause my tranny to over heat To the point of boiling the fluid?

Second the heater core, and water pump went out within 2 days of each other, and thus started all the boiling of tranny. Is this all related to a radiator issue?

 

welcome ot FTE.
when you say "the lockup issue "
are you referring to the trans hunting for a gear to be in at around 35 MPH? it seems like it is constantly shifting between direct and OD, or like the converter is locking and unlocking?
if so, try doing a trans service.
hunting is the transmissions way of telling you it needs fluid and filter changed.
trans service should be done every 30-35k miles.

 

I believe that it is more of a torque convertor lock up problem rather than a hunting or slipping problem.

 

do you have a trans temp gauge? if so what temp is it running? if not,how do you know it's overheating? how does the fluid look now? is the od cancel light flashing? did you pull the codes? hows the fluid level? did the converter unlocking issue just start at the same time the water pump went or sometime before?

 

I do not have a Trans temp gauge. But it very obvious that the Trans is over heating it is boiling all the fluid out of it. The o d light did flash when this happened. Haven't pulled codes. The locking and unlocking has been an ongoing issue for sometime although seems to be getting worse. The actual boiling of the Trans just started. I'm praying that the water pump is the main issue. But would love to know the location of the tc solenoid so that it can be checked

 

Uh, no. Hunting happens because either the program that is running the transmission isn't very good (that's true on E4OD diesels) or data from one or more sensors isn't right. Old fluid can't cause hunting.

And if the filter needs to be changed it means the transmission is toast. The filter NEVER needs to be changed until the transmission needs to be rebuilt. If there is enough junk in the filter to cause a restriction it means one or more clutches have failed.

 

I guess my question is is the water pump failure one of the reasons why my Trans is boiling over ( it has a trans cooler) and why is the torque converter locking up and unlocking at a steady cruising speed

 

Of course it has a trans cooler. Every automatic has a trans cooler. Yours has two, one in the radiator and one out in front of the radiator.

A bad water pump could contribute to an overheated trans since the radiator does part of the job of cooling the trans.

I think the answer to this is right here:

A bad throttle position sensor, or vehicle speed sensor, or a few others I can't think of off the top of my head can cause this.

 

so the fluid is no good anymore.you'll want to change the fluid out of course including the torque converter (it has a drain and it's easy to get to)
then you'll want to insure the fluid is flowing out of the rear trans cooler line to make sure your cooler(s) are not plugged up.

the trucks cooling system is all fixed now right?
if not,be sure to address any issues.

for the converter randomly unlocking you'll want to start here,looking for anything obvious:
https://www.ford-trucks.com/forums/1...s-harness.html

test and or replace the TPS (if it's over 50k miles,simply for preventive maintenance if nothing else at this time.)
https://www.ford-trucks.com/forums/1...ions-only.html

be sure your brake switch (located up on the brake pedal) isn't faulty.

once you do these,post back with your results.

that's really too bad she was run long enough to boil the atf.had you a trans temp gauge,you would have known to shut her down for the day and just catch a ride.
a temp gauge is worth the money.
a converter unlocked produces more heat,but the old trans of the 80's and before didn't have locking converters.the main issue was probably the lack of radiator cooling due to the failed water pump.....but a quick 2 min test to insure the coolers are not plugged wont hurt.

 

correct you are Mark, i should have worded that differently. filter never really needs to be changed on a properly maintained trans. i just have a habit of changing the filter when i change the fluid.
i have noticed on the E4OD though that after doing a fluid/filter change that the trans stops hunting for another 30k miles.
or maybe it is still doing it, but the customers are just not feeling it until the fluid get 25-30k miles on it.

 

I will post the outo me. Thanks for all the help.