Trans problems

[Tanders]

So I recently done the 5.0 swap in my 99 ranger. Parts out of a 97 mountaineer. I drive it for about a week then I lost pull in OD, and worked its way down too I only had 1st and 2nd. It was still shift, just doesn't pull. Does the pan and the fluid is still new doesn't smell burnt. I need help.

 

[RonD]

Welcome to TRS

You will have a 4R70W automatic transmission.

All automatics run on fluid pressure, the bands and clutches inside need this pressure to hold transmission in a "gear" so it can power the rear wheels(output shaft), slipping clutch means no "pull", just like in a manual transmission.

Reverse requires the highest pressure(175psi), does Reverse work OK?

Reverse is usually the first problem noticed when internal pressure is being lost

The torque converter allows engine to be on when transmission is "in gear" and truck is stopped, it also powers the Main Pump in the front of the transmission, also called the Front Pump, this pump is what makes the fluid pressure needed to make truck "go" and to hold transmission in "a gear".

Did you install the engine and transmission as one unit?

Or did you install the engine and then the transmission?

The torque converter MUST BE installed on the transmission FIRST and then SEATED(pushed in and rotated) into the Front pump slots before transmission can be attached to the engine.
If you don't do this you will damage the Front Pump, and either transmission will not work at all or will fail soon after installation.
Check trans fluid level with engine OFF
Then check it with engine ON
If level is not changing then front pump is not pumping enough fluid.

 

[Tanders]

The fluid level is correct, and it doesn't drop out of gear. Doesn't leak. I had to replace tail shaft to continue using factory transfer case, and all clutches and plates looked almost brand new.
It'll shift into 3rd but won't pull, and won't shift back down to 2nd until the truck has slowed to the point of a normal downshift.

 

[Tanders]

Oh and yes reverse still works.

 

[RonD]

If Reverse still works then it isn't a pressure issue, as far as pump is concerned.

The sprang, or one-way, clutch would be my next "guess" because all I can do is guess without being there, lol, and even then it would be guessing

It can start making a "clicking noise" when one-way clutch is failing but not always.
Start of failure is noticed when shifting into higher gear and you lose connection to rear wheels, i.e. it shifts but when you press down on gas pedal engine RPMs go up but speed doesn't, no "pull"

one-way clutch is only used in forward gears, so it is often called Forward one-way clutch.
As it gets worse you start to lose "pull" in lower gears.

And yes slowing down can get one-way clutch to re-engage to get "pull" back, but it will go away again on next upshift

Read here: http://etereman.com/blog/transmission-care/transmission-components-the-one-way-clutch

 

[Tanders]

Apart from the clicking noise that sounds like it. Thanks for the info. I knew I'd probably have to go back into the trans, but at least now I have some point to start looking.