Auto Tranny Manual Lockup
#1
11-01-2007, 10:17 PM
Auto Tranny Manual Lockup
Auto tranny manual lockup
By my ol buddie AK Ram
The only real difference between year is the wire color that you tap. Other than that, this will work on all 3rd Gen trucks 2003 thru 2006, 47RE or 48RE trans. If you have a 47RE trans, the truck will immediately shift into overdrive when you hit the switch, regardless of speed, unless your at WOT (did that make sense). On 47RE trucks, this works great at the track, but not very good for daily driving unless you lock out overdrive…..then its a blast to use in town. No issues that I am aware of on 48RE transmissions. Your wire colors may be different by year, so definitely check pin numbers before you to tapping. I found some really good pics of this procedure on a 2006 truck on photobucket that I'm gonna "borrow". Hope the guy doesn’t mind. This guy did a real nice job with his install and the pics will help tremendously. It should look relatively the same on all years. CAUTION: The stock converter and shafts are not designed to withstand locked shifts, so be aware and use this at your own risk.
This will make a manual lock-up switch. This will lock the converter in any gear, whether the truck is moving or not. It will not lock the converter if the truck is in neutral, reverse, or park. If you are in drive, 1st, or 2nd, and flip the switch, the converter is going to lock, even if your at idle which will kill the engine. So be careful. The converter locks up normally if the switch is off. Basically, be aware of when your locked.
You will need an on/off toggle switch of some kind, some wire, and a wire tap. The idea is to take the 12v converter signal and ground it with the toggle switch. When this signal drops below 6v, the converter locks. You will also need to run a short jumper wire between two pins on the transmission relay in the fuse box under the hood. This will prevent the ECM from throwing a code P2769, Torque Converter Clutch Circuit Low.
Step 1: Crawl under the truck on the drivers side and look at the transmission. There is a squarish plug and a round 7-pin plug. The wire you want to tap is pin# 7 on the round 7-pin plug. If you take the round plug off, the pin numbers are on the inside (bottom of the plug). The clip holding this plug on is facing to the passenger side. Just push the clip in and pull up on the plug. Find pin# 7 and put a wire tap on the wire going into this pin. On your 2006 truck, this will be the yellow wire with light blue stripe. Everyone else should probably pull the connector and find pin #7 (good light helps see the numbers, they are very small) to ensure you have the right wire. Colors sometimes change through the years.
Run a wire from this wire tap into the cab and connect it to your toggle switch. Connect a wire to the other side of your toggle switch and run it to some metal under the dash somewhere or any decent grounding point. This will ground out that signal when you flip the switch.
Step 2: Now open the fuse box under the hood and find the transmission relay. This will be listed as relay # 59 on the fuse box cover. It's next to the fuse marked 50. Pull the relay (lift straight up) and look underneath for the pin numbers. Put a short piece of wire connecting pins #30 and #87. Make sure this wire has some insulation in the middle as not to short out any other pins. Just wrapped the ends around the two prongs and plug it back into the socket. There is also a pin marked 87A. Careful not to run the jumper to 87A by mistake or you will set the dash light, get a code P2769, and put the truck into limp mode.
Possible problems with codes. There really is only two things that can go wrong and both will be user error.
If there is something wrong with your jumper on the transmission relay (wrong pins, not touching both pins, touching more than just these two pins), it will set a P2729 code. The truck will go into limp mode and not shift out of 3rd gear.
If you forget to unlock your converter and accidentally kill the engine, you will get a code.
Here are the pics of this procedure on a 2006 truck that I mentioned above. This guy did a real nice job with his install.
By my ol buddie AK Ram
The only real difference between year is the wire color that you tap. Other than that, this will work on all 3rd Gen trucks 2003 thru 2006, 47RE or 48RE trans. If you have a 47RE trans, the truck will immediately shift into overdrive when you hit the switch, regardless of speed, unless your at WOT (did that make sense). On 47RE trucks, this works great at the track, but not very good for daily driving unless you lock out overdrive…..then its a blast to use in town. No issues that I am aware of on 48RE transmissions. Your wire colors may be different by year, so definitely check pin numbers before you to tapping. I found some really good pics of this procedure on a 2006 truck on photobucket that I'm gonna "borrow". Hope the guy doesn’t mind. This guy did a real nice job with his install and the pics will help tremendously. It should look relatively the same on all years. CAUTION: The stock converter and shafts are not designed to withstand locked shifts, so be aware and use this at your own risk.
This will make a manual lock-up switch. This will lock the converter in any gear, whether the truck is moving or not. It will not lock the converter if the truck is in neutral, reverse, or park. If you are in drive, 1st, or 2nd, and flip the switch, the converter is going to lock, even if your at idle which will kill the engine. So be careful. The converter locks up normally if the switch is off. Basically, be aware of when your locked.
You will need an on/off toggle switch of some kind, some wire, and a wire tap. The idea is to take the 12v converter signal and ground it with the toggle switch. When this signal drops below 6v, the converter locks. You will also need to run a short jumper wire between two pins on the transmission relay in the fuse box under the hood. This will prevent the ECM from throwing a code P2769, Torque Converter Clutch Circuit Low.
Step 1: Crawl under the truck on the drivers side and look at the transmission. There is a squarish plug and a round 7-pin plug. The wire you want to tap is pin# 7 on the round 7-pin plug. If you take the round plug off, the pin numbers are on the inside (bottom of the plug). The clip holding this plug on is facing to the passenger side. Just push the clip in and pull up on the plug. Find pin# 7 and put a wire tap on the wire going into this pin. On your 2006 truck, this will be the yellow wire with light blue stripe. Everyone else should probably pull the connector and find pin #7 (good light helps see the numbers, they are very small) to ensure you have the right wire. Colors sometimes change through the years.
Run a wire from this wire tap into the cab and connect it to your toggle switch. Connect a wire to the other side of your toggle switch and run it to some metal under the dash somewhere or any decent grounding point. This will ground out that signal when you flip the switch.
Step 2: Now open the fuse box under the hood and find the transmission relay. This will be listed as relay # 59 on the fuse box cover. It's next to the fuse marked 50. Pull the relay (lift straight up) and look underneath for the pin numbers. Put a short piece of wire connecting pins #30 and #87. Make sure this wire has some insulation in the middle as not to short out any other pins. Just wrapped the ends around the two prongs and plug it back into the socket. There is also a pin marked 87A. Careful not to run the jumper to 87A by mistake or you will set the dash light, get a code P2769, and put the truck into limp mode.
Possible problems with codes. There really is only two things that can go wrong and both will be user error.
If there is something wrong with your jumper on the transmission relay (wrong pins, not touching both pins, touching more than just these two pins), it will set a P2729 code. The truck will go into limp mode and not shift out of 3rd gear.
If you forget to unlock your converter and accidentally kill the engine, you will get a code.
Here are the pics of this procedure on a 2006 truck that I mentioned above. This guy did a real nice job with his install.
The following 2 users liked this post by Whit:
peterkiewit (05-01-2008),
puffsmokeonya (09-16-2009)
#5
04-11-2008, 07:15 AM
Diesel Fan
Join Date: Mar 2007
Location: VT
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I don't think I am using the relay part. Just ran a wire from tranny #7 to switch and then to ground. Truck is a 2005 with 48RE.
I didn't even need the reisitor (33 ohm) and I only set a code when I forget that the switch is on until I start to come to a stop. The truck clunking and shaking remind me that the switch is still on.
Go to a auto store and use their diag. tool and reset back to no codes. Use to happen a lot when first trying it, now getting much better about turning on only when needed.
I didn't even need the reisitor (33 ohm) and I only set a code when I forget that the switch is on until I start to come to a stop. The truck clunking and shaking remind me that the switch is still on.
Go to a auto store and use their diag. tool and reset back to no codes. Use to happen a lot when first trying it, now getting much better about turning on only when needed.
#7
04-14-2008, 08:00 AM
ok, some questions
What would be the benefits to doing this mod? does it wear the tranny?
I use mine as a daily driver and i also haul fire wood and occasionally tow.
I know in 4 hi or 2 hi with a bed full of firewood I have to really give it some gas to get it moving when backing up hill or anytime there is an obstical. would this help me? I usually just put it in 4 lo so I dont have to use some much gas pedal but would rather just be able to do it in high.
would this be a good circumstance to use it?
What would be the benefits to doing this mod? does it wear the tranny?
I use mine as a daily driver and i also haul fire wood and occasionally tow.
I know in 4 hi or 2 hi with a bed full of firewood I have to really give it some gas to get it moving when backing up hill or anytime there is an obstical. would this help me? I usually just put it in 4 lo so I dont have to use some much gas pedal but would rather just be able to do it in high.
would this be a good circumstance to use it?
Last edited by GRI; 04-14-2008 at 08:11 AM.
#8
04-15-2008, 10:49 PM
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I am interested in this, but really have no idea why you would do it, or how you would use it... properly...
#9
04-16-2008, 09:18 AM
Diesel Fan
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#10
05-01-2008, 03:46 PM
Newbie
Whitmore, thanks for the photos and the write up. I just joined this site so I can comment. I've researched this mod alot on the internet and I am planning to do it, but I have a slight problem. My truck is still under warranty but I have a plan to get around that too.
I am not really keen on the mechanical wire splicing for pin #7 as you describe it. Being a fellow Wyoming guy, the mud and slush tend to make those types of wire connections a big problem over the long term. My solution is to find BOTH male and female parts of the connector which will enable me to build an inbetween piece with a soldered connection all sealed up in silicone or something. The beauty of this jumper with the connector plugs on each end will be that I can remove it from the truck, if I have to go to the dealer! (I can figure out how to stash the wiring in the cab; switch/resistor/ground lug, fairly easily.)
The question is: WHERE IN THE HECK CAN I FIND THE TRANSMISSION SIDE PLUG? I've searched high and low online. Any help would be awesome. Here is a link to purchase one end: A500 A518 42RE 46RE 47RE transmission harness repair but a junkyard will do. The tranny side is the problem.
Further, to answer GRI and dirtydodge05's question, I want to do it for city, deadhead driving. I have several long streets or roads where the speed/speed limit is 40-45 mph. My converter locks consistantly at 49 mph. If my speed drops to 40-45 and I lean on the throttle just slightly, very lightly, the converter unlocks with an rpm gain. My plan it to get up to 49 and have it lock and then cruise at 40-45 mph where the fuel savings are. My son has a manual transmission CTD and he shifts 1-3-6 (skipping gears) and lumbers around town in 6th gear, just over 1000 rpm and he is killing me in the mileage department. Diesels are made to lug down which makes them happy. I'm pretty sure that my truck will tell me if I lug it down too much (too low of rpm) after I find my connectors and put this mod in place.
Please send connectors!
I am not really keen on the mechanical wire splicing for pin #7 as you describe it. Being a fellow Wyoming guy, the mud and slush tend to make those types of wire connections a big problem over the long term. My solution is to find BOTH male and female parts of the connector which will enable me to build an inbetween piece with a soldered connection all sealed up in silicone or something. The beauty of this jumper with the connector plugs on each end will be that I can remove it from the truck, if I have to go to the dealer! (I can figure out how to stash the wiring in the cab; switch/resistor/ground lug, fairly easily.)
The question is: WHERE IN THE HECK CAN I FIND THE TRANSMISSION SIDE PLUG? I've searched high and low online. Any help would be awesome. Here is a link to purchase one end: A500 A518 42RE 46RE 47RE transmission harness repair but a junkyard will do. The tranny side is the problem.
Further, to answer GRI and dirtydodge05's question, I want to do it for city, deadhead driving. I have several long streets or roads where the speed/speed limit is 40-45 mph. My converter locks consistantly at 49 mph. If my speed drops to 40-45 and I lean on the throttle just slightly, very lightly, the converter unlocks with an rpm gain. My plan it to get up to 49 and have it lock and then cruise at 40-45 mph where the fuel savings are. My son has a manual transmission CTD and he shifts 1-3-6 (skipping gears) and lumbers around town in 6th gear, just over 1000 rpm and he is killing me in the mileage department. Diesels are made to lug down which makes them happy. I'm pretty sure that my truck will tell me if I lug it down too much (too low of rpm) after I find my connectors and put this mod in place.
Please send connectors!
Last edited by peterkiewit; 05-01-2008 at 03:53 PM. Reason: more info
