4.0 transmission to 2.9 transmission?

[SWE_lollo03]

So i have a 1988 2.9l Ranger with the a4ld but it has the wrong bellhousing and i found a used a4ld from a 4.0l Ranger from 1992 and so I want to use that transmission instead is it just a plug-in ir is there more cables or just the same gearbox?

 

[RonD]

1988 Ranger computer may only have 1 automatic transmission solenoid control for A4LD
1989 and up A4LD needs 2 solenoid control

There is the solenoid plug-in on drivers side of transmission, it will have 2 wire(1 solenoid) or 3 wires(2 solenoids)
So no, you couldn't use a 2 solenoid transmission with a 1 solenoid computer, you would have no OverDrive

But some late 1988 Rangers did come with 2 solenoid computers and transmissions so check yours

2.9l and 4.0l used same bell housings, as those engines used the same Block

 

[SWE_lollo03]

Are those the cables above the oil pan beside the Gear shifter?

 

[RonD]

Yes, either a 2 or 3 wire connector in front of the gear shift

There is also an NSS(neutral safety switch) connector ABOVE gear shift with 4 or 5 wires, its the same on all A4LDs regardless of year, this prevents starting "in gear" and also activates Reverse Lights(backup lights)

 

[SWE_lollo03]

Okay so i wont have to bother with that?

 

[ferlar]

Hello Don, my 88 2.9 doesn't want to go into overdrive. I got a proven new transmission from a friend and still the same problem. After reading your post I got the truck on a lift and took the enclosed pics. I wonder what you can tell from them. I think my model is the one with the two solenoids but I'm not sure. Appreciate so much your opinion and also what should I do next.

 

[RonD]

Look here: https://www.explorerforum.com/forums/media/a4ld-specification-chart-from-transgo.39537/full

Lower right, if trans has a 2 prong plug it has 1 solenoid for TCC, if 3 prong then it has 2 solenoids, TCC and OD

Plug is on drivers side in front of shifter just above pan, not above shifter, thats the NSS switch


And look at the trucks plug, same applies, 2 wires means no OD control, just TCC, 3 wire has TCC and OD control from computer

1988 was transition year, could have either, 1989 and up were all 3 prong and 3 wire

 

[ferlar]

Thank you so much Ron for your explanation of the different types of A4LD transmissions. Yesterday I put my truck on a lift and took a good look at the connectors. I was happy to see that because my truck is an 88 but I supposed is one of the later ones with the two solenoids transmissions.
Now that we got that defined I still need to find the problem with my overdrive. As I mentioned before, I have replaced the transmission with one that was working well in another truck but it is not in mine. I have checks the cables -as much as I can- and don't see anything disconnected. Could it be the computer? Is there any way to troubleshoot that?
So grateful to have this forum and you guys out there.
Fernando

 

[RonD]

Check that the center wire on the 3 wire plug has 12volts with key on, if not then that's the problem

 

[ferlar]

Ok, we're getting closer all the time. I'll check that on Monday. What if it doesn't? Is there a fuse or a relay somewhere?
Thanks again Ron.

 

[RonD]

No, no separate fuse
It gets the 12volts from the EEC fuse via EEC relay
Red wires, they power the EEC(computer), fuel injectors, spark system, all other solenoids, and fuel pump relay
So engine wouldn't start if that 12v power system wasn't working
But wires break