4+3 Disconnect?
Thread Starter
Instructor
Joined: Apr 2008
Posts: 171
Likes: 1
From: west chester pennsylvania
4+3 Disconnect?
I know theres 10,000,000 4+3 threads, but after looking through the first few pages, I have not seen anything to help me.
I had done an ECM mod that practically stopped the overdrive after first gear. This worked fine up until the other day.
I had my sitting lifted on jackstands for about 2 weeks waiting for a steering rack to come in. After I dropped the car and drove it, somthing wasnt right.
It feels like the car is always in overdrive now. There is about a second delay after hitting the throttle before the car goes. The tach goes up but no torque for a bit. When its in gear without any throttle, the OD kicks in and out over and over, OR just stays in a real high OD gear.
Any ideas?
Is there any way I can just cut the +3 and make it a basic 4 speed and not have to deal with the od i never use?
Thanks in advance.
I had done an ECM mod that practically stopped the overdrive after first gear. This worked fine up until the other day.
I had my sitting lifted on jackstands for about 2 weeks waiting for a steering rack to come in. After I dropped the car and drove it, somthing wasnt right.
It feels like the car is always in overdrive now. There is about a second delay after hitting the throttle before the car goes. The tach goes up but no torque for a bit. When its in gear without any throttle, the OD kicks in and out over and over, OR just stays in a real high OD gear.
Any ideas?
Is there any way I can just cut the +3 and make it a basic 4 speed and not have to deal with the od i never use?
Thanks in advance.
Team Owner
Joined: Dec 1999
Posts: 34,873
Likes: 487
From: Lacey WA RVN 68-69
NCM Sinkhole Donor
According to his profile he has an 87.
You can also try disconnecting the wire harness at the OD relay on the firewall. There are two relays (one in front of the other) between the brake booster and the distributor. The OD relay is the front one while the one closest to the firewall is the fuel pump relay.
What change did you make to the ECM to make the OD unit operate differently??
You can also try disconnecting the wire harness at the OD relay on the firewall. There are two relays (one in front of the other) between the brake booster and the distributor. The OD relay is the front one while the one closest to the firewall is the fuel pump relay.
What change did you make to the ECM to make the OD unit operate differently??
Le Mans Master
Joined: Sep 2006
Posts: 6,050
Likes: 147
From: Phoenix AZ
2021 C4 of the Year - Modified Finalist
I installed a 4+3 in my 57 chevy pickup, and I used the engage switch with two relays to run the trans.
What you can do, is to temporarily add an engage harness with two relays to manually engage and disengage the trans to check for it's operation.
When you discover it is or isn't the trans, you can reconnect the car's original wiring, and troubleshoot the ECM.
I can help you with the wiring diagram if you want.
I use the 4+3 sometimes as a 6 speed, mostly as a 5 speed. It is really a close ratio4 speed and a wide ratio 4 speed all in one box.
What you can do, is to temporarily add an engage harness with two relays to manually engage and disengage the trans to check for it's operation.
When you discover it is or isn't the trans, you can reconnect the car's original wiring, and troubleshoot the ECM.
I can help you with the wiring diagram if you want.
I use the 4+3 sometimes as a 6 speed, mostly as a 5 speed. It is really a close ratio4 speed and a wide ratio 4 speed all in one box.
Last edited by coupeguy2001; Dec 2, 2008 at 11:03 PM.
Thread Starter
Instructor
Joined: Apr 2008
Posts: 171
Likes: 1
From: west chester pennsylvania
the ecm thing was a step by step guide with pictures that i found online. it kind of worries me that i cannot find it anymore. if i remember correctly, two specific wires were taken out of the ecm plug and connected together. it worked as it was supposed to i believe, it took away OD in all gears after first.
although that was my original cocern, it is NOT the clutch.
i just went out and unhooked the relay. a bunch of the wires were half out and just real grimey. anyway, i took it around the block and it works just as a 4 speed
. so thank you.
is there anything i should do or watch out for now?
although that was my original cocern, it is NOT the clutch.
i just went out and unhooked the relay. a bunch of the wires were half out and just real grimey. anyway, i took it around the block and it works just as a 4 speed
. so thank you.is there anything i should do or watch out for now?
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Pro
Joined: Oct 2005
Posts: 541
Likes: 1
From: Freeport FL
*blink*
I dont know why you would give up the overdrive in 4th. Its great for the highway.
Dont you have a switch somewhere on the shifter or console (I know they moved it around a couple times) to just turn it off?
Advice I have seen given here is to change the fluids early and often (annually). You can find the filter as some oddball ford thing, but I prefer to buy the kit from one of the vendors, as it comes with the gasket. It's said that the gasket is unnecessary, and to use black RTV, but I like the gasket.
Dont bother asking in a chain auto store about it- they'll have no idea what you are talking about.
I dont know why you would give up the overdrive in 4th. Its great for the highway.
Dont you have a switch somewhere on the shifter or console (I know they moved it around a couple times) to just turn it off?
Advice I have seen given here is to change the fluids early and often (annually). You can find the filter as some oddball ford thing, but I prefer to buy the kit from one of the vendors, as it comes with the gasket. It's said that the gasket is unnecessary, and to use black RTV, but I like the gasket.
Dont bother asking in a chain auto store about it- they'll have no idea what you are talking about.
Last edited by Droshki; Dec 2, 2008 at 05:22 PM.
Team Owner
Joined: Dec 1999
Posts: 34,873
Likes: 487
From: Lacey WA RVN 68-69
NCM Sinkhole Donor
It sounds like the wires going into the relay connector was the problem. Afte years of being heated up by underhood temps, these wires can come loose and in this case screw up the operation of the OD.
As far as the filter, it's the same one use in the Ford FMX trannys from the late 60's to early 70's. The filter runs around $7-9 depending on the store. Here's some part numbers:
CarQuest 85926
AC Delco TF184
FRAM FT1024
NAPA ATP14717
Ford D0AZ-7A098-A
None of these filters come with a gasket nor the rubber grommet that is required for the 4+3 OD. A good grade of black RTV (The Right Stuff, or MoPar RTV from a Dodge dealer) is really the best for sealing the pan. You should make sure the pan rails are straight and clean and dry. A 1/4" bead is all that is needed and the bolts don't need to be tight, but they do need to be equally tightened.
Use Dexron II/ III ATF non-synthetic for the fill and it takes a little over 2 quarts. Change the fluid and filter annually or every 12-15K miles.
As far as the filter, it's the same one use in the Ford FMX trannys from the late 60's to early 70's. The filter runs around $7-9 depending on the store. Here's some part numbers:
CarQuest 85926
AC Delco TF184
FRAM FT1024
NAPA ATP14717
Ford D0AZ-7A098-A
None of these filters come with a gasket nor the rubber grommet that is required for the 4+3 OD. A good grade of black RTV (The Right Stuff, or MoPar RTV from a Dodge dealer) is really the best for sealing the pan. You should make sure the pan rails are straight and clean and dry. A 1/4" bead is all that is needed and the bolts don't need to be tight, but they do need to be equally tightened.
Use Dexron II/ III ATF non-synthetic for the fill and it takes a little over 2 quarts. Change the fluid and filter annually or every 12-15K miles.
Team Owner
Joined: Mar 2000
Posts: 83,381
Likes: 87
From: Boston, MA
FYI... 84 was an on/off switch on the center console and 85 was an on/off switch in the shifter ****.
Pro
Joined: Oct 2005
Posts: 541
Likes: 1
From: Freeport FL
The 86-88 models changed from on/off switches to a momentary contact switch in the shift **** and the OD program defaults to "on" when you start the car. All you need to do is press the button once and the program will be off until you hit the button again or turn the car off and on. There are ECM values you can reprogram to make the program default to "off" instead.
FYI... 84 was an on/off switch on the center console and 85 was an on/off switch in the shifter ****.
FYI... 84 was an on/off switch on the center console and 85 was an on/off switch in the shifter ****.
Team Owner
Joined: Mar 2000
Posts: 83,381
Likes: 87
From: Boston, MA
If you take the time to learn the OD program, its easy to live with without even ever turning it off. Hell if you nail the gas in first gear or even just happen to go over a certain TPS value the OD won't even turn on again until the car is puttering along in 4th gear. The software engineers who wrote the code were smart enough to realize if you're hammering the car you probably don't want OD hanging out with you for a while. 
I'm not huge on the people who rewire these things for simple off/on switches. They run the risk of bypassing the built in pressure/speed/RPM safeties and adding extra wear and tear on the tranny causing premature failure.
I'm not huge on the people who rewire these things for simple off/on switches. They run the risk of bypassing the built in pressure/speed/RPM safeties and adding extra wear and tear on the tranny causing premature failure.
Thread Starter
Instructor
Joined: Apr 2008
Posts: 171
Likes: 1
From: west chester pennsylvania
the OD button is on the shifter in 87.
the original reason i did the ECM thing is because the OD went totally wack. It would automatically turn on like it should, but when I clicked it off, it would turn back on in a few seconds and then would kick itself in and out to the point it wasnt practical to drive.
Ill probaly look into fixxing all the flaws, fixing the relay wires, changing fluid and gaskets when I get some time, money , and warm weather.
but I can deal with the solid 4 for now
Safety Car
Joined: Oct 2007
Posts: 4,426
Likes: 229
From: Pennsylvania
Pro
Joined: Oct 2005
Posts: 541
Likes: 1
From: Freeport FL
the OD button is on the shifter in 87.
the original reason i did the ECM thing is because the OD went totally wack. It would automatically turn on like it should, but when I clicked it off, it would turn back on in a few seconds and then would kick itself in and out to the point it wasnt practical to drive.
Ill probaly look into fixxing all the flaws, fixing the relay wires, changing fluid and gaskets when I get some time, money , and warm weather.
but I can deal with the solid 4 for now
the original reason i did the ECM thing is because the OD went totally wack. It would automatically turn on like it should, but when I clicked it off, it would turn back on in a few seconds and then would kick itself in and out to the point it wasnt practical to drive.
Ill probaly look into fixxing all the flaws, fixing the relay wires, changing fluid and gaskets when I get some time, money , and warm weather.
but I can deal with the solid 4 for now
Mine is an early 85 with the factory mounted console button. The car has 31,000 miles and runs perfectly. I use my O/D as a fifth gear as you do. I ALWAYS use the clutch when shifting in or out of O/D and maintain the fluid and filter. Have had absolutely "0" problems with it. Seems as though alot of people just don't know how to use them.
Although I get lazy about clutching it once in a while, Ive never had a problem.
Team Owner
Joined: Mar 2000
Posts: 83,381
Likes: 87
From: Boston, MA
the original reason i did the ECM thing is because the OD went totally wack. It would automatically turn on like it should, but when I clicked it off, it would turn back on in a few seconds and then would kick itself in and out to the point it wasnt practical to drive.
Ill probaly look into fixxing all the flaws, fixing the relay wires, changing fluid and gaskets when I get some time, money , and warm weather.
Ill probaly look into fixxing all the flaws, fixing the relay wires, changing fluid and gaskets when I get some time, money , and warm weather.
Thankfully both are easily fixed.
Team Owner
Joined: Mar 2000
Posts: 83,381
Likes: 87
From: Boston, MA
When I mentioned bypassing the safeties, there have been numerous folks on this board in the past that simply wire up a new switch and relay to the OD, completely bypassing the ECM.
Pro
Joined: Oct 2005
Posts: 541
Likes: 1
From: Freeport FL
