A4LD Won't Shift Out of First

[ExploringNC]

Starting a new thread because now I have a new problem.

Previous thread.

After problem with fuel pressure reg I had planned on doing tranny filter this weekend but I guess I waited too long. Tranny had been not shifting right but would fall in first with a small clunck and then be ok. On way to parts store pulling up to light it made a much harder clunck when it downshifted to first, heard a slit sound of band slipping. Took of in first no problem but now not upshifting at all and no reverse.

Did filter and flushed with all new fluid still no reverse but couldn't get out of garage to see if it shifts out of 1st. While pan off I took a look around and noticed back of 3-4 shift solenoid was loose.

What should I do from here? I plan next on replacing the vacuum modulator and looking into replacing both solenoids.

 

[BrooklynBay]

Did the fuel damage the modulator? Do you have transmission fluid going into the engine? Does this problem occur when it's cold, then slowing disappear as it warms up? If so, then it could be a sticking governor.

 

[ExploringNC]

Nothing in vacuum line from tranny at vacuum tree did not check vacuum line at modulator for fuel. Truck stranded at buddies shop so not here to go out and check real easy. Does it all the time now, on way home it was hot when it happened and yesterday after fluid change. Could a shift solenoid be damaged? How do I get them out? I tried taking retainer clip off and getting them out but they didn't budge, do I have to take VB off to get them out?

 

[BrooklynBay]

The valve body has to be removed on the A4LD in order to remove the 2 solenoids. The solenoids are for overdrive (3-4 shift) & TCC (torque converter clutch). 1st gear is not controlled by the solenoids.

 

[ExploringNC]

Should I be looking at problem in VB or somewhere else?

 

[BrooklynBay]

Since you have a problem with reverse & 1st gear, you should start with the low/reverse servo, and the band.

 

[ExploringNC]

OK now I need help making sure I get right part. Local supplier has a great parts breakdown on there web site that you can just click on a exploded view of the part needed. Here is the list of parts it has for the rear servo.
https://www.wittrans.com/SchematicParts.aspx?Transmission=A4LD/4R44E/4R55E/5R55E&LinkCode=910

How do I know which one I need?

 

[BrooklynBay]

Take out the servo, and inspect the tip. It might be OK, and not chipped. Don't buy parts without examining everything first. The TransTec Vition D ring kit is recommended in place of the standard O rings. Test the low/reverse band with a long phillips screwdriver to see if it has spring action.

 

[ExploringNC]

For $12 I was just going to replace it regardless. I work not far from this supply depo and was going to pick it up over lunch break then I would have it on hand when I get to truck after work. I need to get this running ASAP and don't really want to wait on shipping but if I have to then I have to.

 

[ExploringNC]

If the band was broke or damaged wouldn't it not go into first at all? It's got plenty of power when in first and I don't hear any slipping at all just will not shift. When I took the old fluid out it didn't have the tranny fluid smell at all and just didn't look right but not a burnt smell at all. If the servo shaft got damaged would that cause first gear to not disengage?

 

[BrooklynBay]

The servo & band control 1st gear & reverse.

 

[ExploringNC]

Allright I do believe I found the problem now how much damage was done. I unbolted plate holding rear servo in and servo did not come out, I had to pry a little to get it to come out and it was full of tranny debri. Sidewalls of servo are really gouged and the center shaft has debri in it and is stuck. Camera batteries died so no pics till tomarrow. I checked the band but not sure what I was checking, it was there and moved slightly when I pushed on it but felt intacked.

 

[BrooklynBay]

Were these fragments made out of metal?

 

[ExploringNC]

Small chuncks of metal yes. Got some pics but cheap camera does'nt have a focus when I try to get up close and flash reflection makes it hard to see.

You can see the grooves and how the edge is chewed up and you can kinda see the small pieces wedged in the center.

 

[ExploringNC]

New servo didn't work, still same problem. Looks like I'm gonna have to look for a new tranny. Anything else to check before I go threw all the work of swapping tranny?

 

[BrooklynBay]

Did you use new O rings on the new servo? Does the bore have any deep scratches or gouge marks? Did you check the band to see if it's in the correct position?

 

[ExploringNC]

Did you use new O rings on the new servo? Does the bore have any deep scratches or gouge marks? Did you check the band to see if it's in the correct position?

I did get the new style o-rings and bore did have some gouge marks, I tried sanding them out best I could. I looked up into the bore and the band seat for the servo was right in the center. What exactly should the band feel like when I push on it, should it push back like a spring? When I took the servo out it had allot of like a paste, kinda looked like old copper bars leak. Could the VB have a blockage in it? If the reverse/low band was broke or damaged wouldn't it not go into first at all?

 

[BrooklynBay]

The band should spring back into place. Clean the valve body very thoroughly.

 

[ExploringNC]

Is the band kinda hanging loose likes it's not attacked to anything without the servo in? Not broke or anything just not attached to anything. Should I try replacing the VB with a rebuilt or look for another tranny? I don't want to keep putting money into this tranny but if the VB will fix it then I could really use the money on something else.

I like your thread on usefull threads can I add that to my sig? I'll be sure to give you the credit.

 

[BrooklynBay]

You could add it if you want. One side of the band sits on a tab in the case. The band has a notch for this tab to hold it in place. The servo presses against the opposite side of the band which causes it to grab a drum.