When changing my radiator, do I need to fill the transmission fluid reservoir?

Question

I'm changing the radiator on my 1988 Ford F-150 truck. The tranmission lines go in and out of the reservoir. My dad says that I need to fill that with tranny fluid, but my friend says that I don't have to fill anything. Who's right?

Just to be clear, I know that the tranny fluid and the coolant are in separate areas in the radiator and not to mix them.

To put the question more plainly, do I need to replace the fluid that leaked out when I took the radiator off?

Answer 1

Father knows best.

When you took out the radiator, there was transmission fluid in it. You also leaked a bit from the lines when they were loose. Check your transmission fluid level (level ground, engine running, truck warmed up) and add the correct fluid as needed!

Answer 2

Most cars have two lines running from the transmission to the radiator to cool the transmission fluid. They are side by side at the bottom of the radiator. Either they have been hooked up wrong, or the radiator is defective inside at that area. It's been a very long time since I've worked on a radiator so I am not 100% positive, but that is my guess.

Answer 3

Transmission Radiator

Answer 4

There are no coils in a radiator for the tranny fluid. There is a small tank that sits in the side, or bottom, of the radiator. It holds a pint, at best.

You will lose just a tad when you take the lines off. You'll need a pint or less to replace what is lost.

Just check you level after the tranny is warmed up.

Answer 5

There are 2 separate passageways in the radiator. One where coolant runs through it, the other where tranny fluid runs through it. A small amount of trans fluid comes out when you you disconnect the 2 transmission lines from the radiator, so you probably don't need to top off the trans fluid.

Answer 6

no, an automatic transmission is self bleeding. it will pump the fluid into the cooler and fill it up. you wont incur any damage to the transmission at this time. also always make certain the transmission's output tube is going into the UPPER port in the radiator, especially if someone has changed it before.
be absolutely certain of the three things to do when checking a transmission's fluid level.

HOT.
IDLING.
LEVEL.

make sure the transmission is up to operating temperature. transmission fluid can expand more than one quart's size from cold to hot.

make sure the engine is running at idle so that the transmission's valve body and pump have the correct amount of fluid in them.

make sure the vehicle is on level ground. you are after all taking a reading from the pan.

Answer 7

if you look at your radiator there are plastic tanks on the side. this is a separate cooler for the Tranny. when you remove those line from the rad some tranny fluid will come out. fill the rad with coolant. use a 50/50 mix or one gallon of coolant to one gallon of water. when the truck is running and at full engine temp check your tranny fluid. add if it is low on the dip stick. if you need to add you add the fluid threw the dip stick.

Answer 8

I've never seen so much garbage advice in my life. There is no transmission reservoir. Those transmission lines just go through the radiator for cooling. You just check and top off your transmission fluid like you always do.

Answer 9

YOUR TRANSMISSION LINES GO INTO, THROUGH AND BACK OUT OF THE RADIATOR TANK.INSIDE THE TANK IS A
COIL SET THAT LOOKS LIKE YOR RADIATOR ONLY MUCH SMALLER.THIS IS HOW THE TRANSMISSION FLUID GETS COOLED DOWN AS IT IS PUMPED THROUGH THE LINES. THE ANSWER IS NO, YOU DO NOT PUT TRANSMISSION FLUID IN THE TANK,ONLY COOLANT/ANTI-FREEZE.

Answer 10

I think the term Reservoir speaks for itself but if you're still unsure go to a ford website and check out manuals. A friend of mine gets tips in the mechanics chat rooms. Good Luck