Transmission Fluid Removal ?

[TJMIV]

Have a friend that want`s me to install a Mag-Hytec DD pan on his 04. 5 3500 4x4 . Truck has about 77,000 miles on it now and is going to start towing a toy-hauler. What is the best way to get as much of the old fluid out of the torque converter. Is this something that is giong to have to be done with a specialized piece of equipment? Any help would be greatly appreciated.

 

[LRutigliano]

Best way I have come up with is to wait at least a whole day after parking to allow the TC to drain. If you wait longer, that is even better.



If you are not satisfiied that you got out enough of the old stuff, drive it for a while and then drain again with the Mag-Hytec drain plug (much easier) and refill again.



Don't backflush and don't disconnect anything, you may just create additional problems such as leaks or plugging up something internal to the transmission.



Don't forget the put all of the fluid you drain into 1 gallon milk jugs and measure what you took out. Then add the additional 3 qts or whatever the Mag-Hytec holds.



The low to high mark on the dipstick is only 8 or 12 oz, so if you overfill, you can easily drain some out with the drain plug.



With the Mag-Hytec, expect to buy about 12 qts of ATF+4. With my PML, I needed 10 qts with a filter change.



Good luck.



Louis

 

[rbattelle]

Best way I have come up with is to wait at least a whole day after parking to allow the TC to drain. If you wait longer, that is even better.

Isn't there an anti-drainback valve that would prevent the torque converter from draining?



Ryan

 

[LRutigliano]

There might be, I don't know. What I do know is that my TC drains into my pan after the truck has been sitting for a while.

 

[MMeier]

There might be, I don't know. What I do know is that my TC drains into my pan after the truck has been sitting for a while.

How do you "know" this?

 

[LRutigliano]

I think I know based on two observations:



- When my truck sits for a while and I start it, I put it reverse after starting and have to wait momentarily for the truck to move and for the TC to fill.



- when my truck sits for a while and I check the transmission fluid level, the level is about 2" or more above the "full" mark on the dipstick.

 

[MMeier]

k, just asking. Sounds legit.

 

[rbattelle]

LRutigliano, I wonder if you've got a faulty drain back valve?

Ryan

 

[cerberusiam]

There might be, I don't know. What I do know is that my TC drains into my pan after the truck has been sitting for a while.

TC won't completely drain even sitting overnight with a leaking drain back valve. It will only drain half of it.



Best way to get the old fluid out of the TC and cooler lines is remove the rear cooler line from the trans, add a short chunk of hose into a drain bucket, and once the new pan is on and trans filled start the truck in neutral and let the trans pump the old fluid out. Once the fluid flow slows, shut off truck, refill trans, and repeat.



This will pump out most of the old fluid. With the factory pan it takes 16 quarts to change the fluid, add whatever the additional amount is for deep pan. Once you have used up your stock the fluid will be changed.