A4LD trans OD not working

[XploreAlaska]

Okay so I'm tired of driving down the road at 65 mph / 3100 rpm, I've decided that the OD dosent seem to work because there is no difference in drive and overdrive at that speed, I've has 3 first gen explorers and they have all had this problem (and one 92 ranger that wouldn't redline at 70 mph) so I'm guessing its a common thing. I've never had the knowledge to know what problem to target. Me being like most men with a gearhead vein in their body I refuse to take it to a shop. So, where do I start to get this problem under controll??

 

[BrooklynBay]

Check the output of certain sensors like the VSS or the TPS. The PCM commands a ground signal to the 3-4 shift solenoid. Other possibilities could be that the overdrive servo is dried out, and leaking, the overdrive band is either out of spec or broken or it could be a valve body problem.

 

[XploreAlaska]

Time to bust out the repair manual. Thanks for pointing me in the right direction before I just start replacing ****.
Is this more often than not a valve body problem when this happens?

 

[BrooklynBay]

As previously stated, it could either be electrical or mechanic. Check the resistance of the overdrive solenoid to start.

 

[XploreAlaska]

If there was something wrong with the tps wouldn't it run like sh*t? And as for the pcm how do I check to see if I've got a bad ground going to the od servo?

 

[BrooklynBay]

Since the PCM is what commands a ground to the solenoid, the only way the solenoid wouldn't get a ground is if there is either no ground to the PCM (the vehicle wouldn't start) or if you have a bad sensor (the PCM doesn't know enough to command a ground to the solenoid).

 

[Four0Sport]

i have a similar problem.. i have all 4 gears, but my torque converter wont lock up. a friend who has been a long time ford tech told me that the main culprit for the TC not locking and/or 4th gear not engaging are the 3-4 shift solenoid and the TCC solenoid both of which are replaceable.. i think you have to remove the pan, screen, and valve body to replace these parts? someone correct me if im wrong. i havnt done anything to it bc i hardly drive the vehicle on the interstate but the more i do the more i think about having someone help me replace the TCC solenoid.

hope this helps,

-Jack

 

[BrooklynBay]

You are correct that you have to drop the pan, but first check the solenoids at the 3 prong connector before doing this. The entire valve body has to be removed in order the remove the solenoids. The later model transmissions such as the 4R55E & 5R55E have a removable solenoid bracket that allows you to remove the solenoids without removing the valve body.

 

[Four0Sport]

is the procedure for checking the solenoids that the external connector posted somewhere on the site? searched real quick but didnt come up with anything.

 

[BrooklynBay]

The connector has 3 pins. The middle is the common (+), and the other 2 pins are for the other sides of the solenoid which the PCM commands (-).

 

[Four0Sport]

ive been reading some other threads and a few of them mention cruise control problems being associated with trans problems.. could anyone explain this further, is it a VSS problem or what bc i thought first gens were vaccum servo cruise setups, but i could be wrong

 

[BrooklynBay]

The cruise control needs a feedback signal to know how fast you are going.

 

[Four0Sport]

makes sense. lol

 

[XploreAlaska]

So you hook 12v to the center pin and ground one of the outers and I'm supposed to listen for a click of the solenoid activating?

 

[BrooklynBay]

You could do that, but I don't know if you could hear it with the pan on. You are better off using an ohm meter to check it out first. Look for a reading of approximately 25-40 ohms on each one.

 

[Four0Sport]

i know what im doing while i have the rear leafs off again. good thing i bought that nice digital multimeter

 

[chetzar]

Im actually glad I ran across this thread, because my OD is doing the same thing, and my CC is not working, gonna have to give this one a shot tommrow!