Need some quick advice

[Axial32]

Okay, have a 5.0L with the 4R70W and the AWD tcase. I am having issues with either my tcase or my transmission. It moves in reverse, but soon as I put it in drive, 1, 2... does NOThing now. It was the last couple days slowly moving and then it would catch up and drive fine. So my question is... Would this be my transmission going out, or my Tcase.?

Thanks a ton,
Axial32

 

[gmanpaint]

Sounds like the trans to me.

The 4404 is a pretty straight forward t-case with minimal parts inside, nothing like the 4405 case internals with a clutch.

 

[Axial32]

Yeah, but I've heard of the awd v8 tcases going out. Do you know what it would be doing if the tcase had gone out?

 

[gmanpaint]

If the t-case went bad, it wouldn't do anything. Its a direct drive type case. Check out Glaciers 4404 thread in the trans section. You will see his pics of how simple a case it is.

 

[Axial32]

It had been acting funny for the last couple days wear it didn't want to move unless i let it warm up for a few minutes, and then checked fluid and added some just to be safe, then drove it out to my buddies place where then it lost all forward movement, but reverse works perfectly fine. Idk what to do or check first.

 

[Axial32]

i haven't found anything from glacier on the bw4404

 

[sean kane]

Sounds like the transmission. Either the seals are so hard from alot of heat and being old around the apply piston in the forward clutch that its letting the oil blow by the piston, or the forward clutch has burned up the frictions and cannot apply.

The forward clutch is applied in all forward gears, the reason reverse works is because it is applied from the low/reverse piston in the bottom of the case.

Without looking at my book dont qoute me but in reverse I think the direct clutch and low reverse clutches are applied.

In forward gears the forward clutch and what ever range your in those clutches or band(s) apply.

The reason it took so long to apply before it went out is because you were waiting on the oil to fill the cavity in the drum behind the piston and the piston seals were either hard and letting the oil go by until it warmed up and the seals expanded or the clutch frictions sre so warn the piston had to travel along way to apply enough pressure to the frictions before they would engage.

You can look at a diagram and hook a transmission pressure gauge to the proper port and test the pressure in forward gears. If it is not within spec you have found your problem.

Hope this helps.

 

[gmanpaint]

Sorry, it was a thread made by gavin.

http://www.explorerforum.com/forums/showthread.php?t=225515

 

[Axial32]

Hey thanks Sean Kane, and thanks for the link gman. One more thing sean, which port is it? being the 4r70w, i believe it's the top but i'm not sure, and not sure about the psi it's suppose to be running either.
Thanks again guys.