T-case diagnosis - to open or not.....

[halo15]

Finished with my valve body install (99 ford ex 100K + miles) with the 5r55e tranny. Located the blown gasket and replaced with new updated version valve body. Thought my problems were over but the OD light started blinking again with the hard shifts and limp mode. Seems the pressure went down a bit with the tranny not jumping into gear out of park but that's about it. Still revs and misses with no clue accept the t-case. Would a pressure guage even help diagnosing while in limp mode?

Only code I get is the P1729 4X4 switch.

I tested the 4X4 and was able to get the front engaged disengaged with no issue with the T-case motor switching and the lights coming on to show activted/deactivated

Could the T-case be the problem with what's going on even though the 4X4 engages? I was thinking that when I lost all gears in front of my garage and couldn't get the car in park with the vehicle running (severe grinding) that the T-case might be the cause of all my headaches but It would really suck dropping it and opening to find nothing.

The original tranny oil was red with nothing found in the pan when I changed out the old VB

Any thoughts on T-case being the issue???? Thanks

 

[IZwack]

When you heard grinding trying to get the vehicle into park - that was due to the transfer case being in the Neutral position. As you tried to engage park, the transmission's internal and output shaft was still spinning since the transfer case was disconnected from the brakes. The proper shutdown procedure in this event is to step on the brakes, shut down the engine and wait a few moments for the entire drivetrain to stop spinning, then engage Park.

Having said all that, I'm not sure this at all related to the limp mode issue especially since in the 98+ Explorers, there is no VSS sensor at the t-case's output flange (which was used by the transmission in the 97 and older models).

 

[halo15]

Thanks for the info....

So it sounds like the tranny itself then.

Are you saying that a T-case malfunction/break would never trip the OD light blink issue or a code? If that's the case, than it's back to the drawing board on this tranny....

 

[IZwack]

Thanks for the info....

So it sounds like the tranny itself then.

Are you saying that a T-case malfunction/break would never trip the OD light blink issue or a code? If that's the case, than it's back to the drawing board on this tranny....

I'm not 100% sure but a few of us with 98+ Explorers have swapped in manual transfer cases with zero electronic connections and the transmission shifts just fine -- as long as the shift motor is still connected (I think). If you can borrow a shift motor from somebody, maybe swap that in for a few minutes and see if it makes any difference. There's also a shift motor rebild diary somewhere so maybe you can "rebuild" the shift motor - wouldn't cost much to do so.

 

[halo15]

I was planning on looking at the shift motor but figured it was working since the t-case engages and i hear the motor going

Saw the rebuild diary

Will be looking at it again tonight

Thanks

 

[snoranger]

Only code I get is the P1729 4X4 switch.

I tested the 4X4 and was able to get the front engaged disengaged with no issue with the T-case motor switching and the lights coming on to show activted/deactivated

Could the T-case be the problem with what's going on even though the 4X4 engages? I was thinking that when I lost all gears in front of my garage and couldn't get the car in park with the vehicle running (severe grinding) that the T-case might be the cause of all my headaches but It would really suck dropping it and opening to find nothing.


Any thoughts on T-case being the issue???? Thanks

I've opened quite a few RBV t-cases over the years now. I've found that when it grinds going into park (like IZ said) its in neutral. The 2 most common causes i've seen:

The case is worn where the shift rail is seated.
-or-
The little plastic "wear pads" on the shift fork are worn out or damaged.


Either one will stop it from fully engaging high or low. As soon as there is torque applied, it jumps out of gear into neutral.

I dont know if it would cause the truck to go into limp home mode.

 

[halo15]

Thanks for the info - really appreciate the input....

I'm able to drive the vehicle with no nore grinding into park but the gears are all over the place - apply gas - hops into reverse, drive etc.... and never able to get out of the first couple of gears but I'm fearing a tranny pull next...

Hope it's the t-case at this point.....