Homemade full manual 4L80E

[Yachtcare]

Saw this posted on youtube, thought it was pretty interesting. He put a 4L80E behind a carbureted small block in an earlier truck, wired up the tranny to switches and shifts it that way, without a computer. Gives a pretty good explanation in the video of how it all works in conjunction with the mechanical linkage, etc. For a certain small segment of the 6.5L population with 4X4 trucks, that want to swap their DS4 for a DB2 injection pump, this could be valuable info.

Seems fairly straitforward, but the only question I would have is if it would be possible to vary the line pressure rate with the use of a potentiometer, similar to making a boost fooler for the 6.5. Maybe one of the gurus here with better knowledge of what makes the force motor work can shed some light.

www.youtube.com/watch?v=ozbWf_QsPrw

 

[THEFERMANATOR]

JAKES makes a box with harness you can buy for what it would cost to build that set-up that does the same thing.

 

[Will L.]

Yes, but if you buy the Jake's set up that you don't get to have the triple switch in the all steel – design.

 

[Yachtcare]

JAKES makes a box with harness you can buy for what it would cost to build that set-up that does the same thing.

Jake's is over $200.00 with shipping. This looks like three $1.29 switches, and some wire to extend a spare cut down trans harness. All of which I already have.

Jake has already told me that line pressure runs full tilt with his setup. This guy says his does also. Overheat of the fluid is the likely result.

I was wondering if there was a way to adjust line pressure manually, as I said, with the use of something along the lines of a "dimmer" switch sort of setup. How does the computer manage line pressures with the force motor?.....by varying voltage output? or some other magical/computer generated method that cannot be replicated with a simple switch?

 

[THEFERMANATOR]

Jake's is over $200.00 with shipping. This looks like three $1.29 switches, and some wire to extend a spare cut down trans harness. All of which I already have.

Jake has already told me that line pressure runs full tilt with his setup. This guy says his does also. Overheat of the fluid is the likely result.

I was wondering if there was a way to adjust line pressure manually, as I said, with the use of something along the lines of a "dimmer" switch sort of setup. How does the computer manage line pressures with the force motor?.....by varying voltage output? or some other magical/computer generated method that cannot be replicated with a simple switch?

It uses a pulse width modulated voltage signal to the force motor to vary line pressure. not sure how well it would work with a standard resistor controlling voltage to the force motor. The JAKES kit when it first came out was only $70, guess they decided to cash in on it.

 

[3500GMC]

One could use a 6.2 vacuum pump, the tps 'valve' for a cucv then contact TransGo for one of their 4L80E kits that uses a classic TH400 modulator valve to control line rise. Perhaps?

 

[billyg38120]

Jake's is over $200.00 with shipping. This looks like three $1.29 switches, and some wire to extend a spare cut down trans harness. All of which I already have.

Jake has already told me that line pressure runs full tilt with his setup. This guy says his does also. Overheat of the fluid is the likely result.

I was wondering if there was a way to adjust line pressure manually, as I said, with the use of something along the lines of a "dimmer" switch sort of setup. How does the computer manage line pressures with the force motor?.....by varying voltage output? or some other magical/computer generated method that cannot be replicated with a simple switch?

Jakes Performance is $590 IF you buy his trans. Not a very good TCM in my opinion. It may shift hard but high line pressure at IDLE WILL DRAG THE CONVERTER CLUTCH and inside the transmission, life (after 10to 30k miles or so) will need a converter and the shops will scare you into an overhaul with expensive upgrades. (I've seen this numerous times)
If you purchase a GM TCM, make your own harness (Just 2 ISS/OSS ends which are Coolant sensor connectors, Trans connector at the bulkhead and a used DRAC) you can control your own trans for less $ and have MORE control over shifts and Pressures. PROMs can be altered using Tuner Pro and my files to change calibrations and set ups. It will work for gasoline carb engine to EFI. (I used a simple HEI module along with the trucks HEI to derive the engine spd signal.)

 

[THEFERMANATOR]

Jakes Performance is $590 IF you buy his trans. Not a very good TCM in my opinion. It may shift hard but high line pressure at IDLE WILL DRAG THE CONVERTER CLUTCH and inside the transmission, life (after 10to 30k miles or so) will need a converter and the shops will scare you into an overhaul with expensive upgrades. (I've seen this numerous times)
If you purchase a GM TCM, make your own harness (Just 2 ISS/OSS ends which are Coolant sensor connectors, Trans connector at the bulkhead and a used DRAC) you can control your own trans for less $ and have MORE control over shifts and Pressures. PROMs can be altered using Tuner Pro and my files to change calibrations and set ups. It will work for gasoline carb engine to EFI. (I used a simple HEI module along with the trucks HEI to derive the engine spd signal.)

There manual control box is $200, and the OPTISHIFT is $590(less if you buy a trans from them). We have a vendor here who carries the OPTISHIFT, and he was very happy with his. TUNERPRO is also an option, bu finding good CAL files for the diesel stuff seems to be a mystery as those who have them don't share them.

 

[Yachtcare]

If you purchase a GM TCM, make your own harness (Just 2 ISS/OSS ends which are Coolant sensor connectors, Trans connector at the bulkhead and a used DRAC) you can control your own trans for less $ and have MORE control over shifts and Pressures.

Wherein lies the problem....... The 4X4 tranny only has the ISS sensor, the OSS sensor is located in the transfer case and sends a different signal to the prom, which obviously any 2wd TCM will not be able to read. YES, a sensor can be installed in the case, but the reluctor ring on the output shaft is not there. While several 4L80E sites claim the reluctor ring was installed on trannys up to the '97 model year, my early built (11/93) '94 does not have the reluctor ring. Confirmed by removing the metal plug in the case where the TOSS usually lives, and peeking inside.

If I am to swap to a DB2 IP, I have to find a work around to make the tranny shift. I don't mind manual shifting if I get some reliability out of the truck, which has continued to erode to none, after five years, and all the reliability mods I could throw at the DS4.

The current tranny has over 300K and needs a rebuild anyway, so I'm not to adverse to throwing a couple of experiments at it. But I have to get the truck to run first, then I gotta make it shift.

 

[THEFERMANATOR]

Wherein lies the problem....... The 4X4 tranny only has the ISS sensor, the OSS sensor is located in the transfer case and sends a different signal to the prom, which obviously any 2wd TCM will not be able to read. YES, a sensor can be installed in the case, but the reluctor ring on the output shaft is not there. While several 4L80E sites claim the reluctor ring was installed on trannys up to the '97 model year, my early built (11/93) '94 does not have the reluctor ring. Confirmed by removing the metal plug in the case where the TOSS usually lives, and peeking inside.

If I am to swap to a DB2 IP, I have to find a work around to make the tranny shift. I don't mind manual shifting if I get some reliability out of the truck, which has continued to erode to none, after five years, and all the reliability mods I could throw at the DS4.

The current tranny has over 300K and needs a rebuild anyway, so I'm not to adverse to throwing a couple of experiments at it. But I have to get the truck to run first, then I gotta make it shift.

The reluctor ing was installed in 91-93 4L80E's as the 91-93 trucks with one and 4X4 used it. The ECM uses the same signal from the VSSB wether it is a 2WD or 4WD, the problem comes in with 4low. You can have a PROM burned for the OBD1 ECM to shut off engine functions and still have the 4X4 switching in it whereas the aftermarket controllers don't seem to be able to do this. You CAN add a reluctor ring to your current 4X4 4L80E, but they are rather hard to find I understand(and break very easily when you remove them). Installing a reluctor ring to the output is the easiest way to make one work as that eliminates the need for the ECM to factor in the 2.72:1 low range when in 4low and allows the use of most any shift controller box. Or you can go with a custom PROM chip in your current ECM to shut off engine functions, add a TPS to the DB2, and have it work that way(you would need to retain the crank sensor for the engine speed portion).

 

[great white]

Wherein lies the problem....... The 4X4 tranny only has the ISS sensor, the OSS sensor is located in the transfer case and sends a different signal to the prom, which obviously any 2wd TCM will not be able to read. YES, a sensor can be installed in the case, but the reluctor ring on the output shaft is not there. While several 4L80E sites claim the reluctor ring was installed on trannys up to the '97 model year, my early built (11/93) '94 does not have the reluctor ring. Confirmed by removing the metal plug in the case where the TOSS usually lives, and peeking inside.

If I am to swap to a DB2 IP, I have to find a work around to make the tranny shift. I don't mind manual shifting if I get some reliability out of the truck, which has continued to erode to none, after five years, and all the reliability mods I could throw at the DS4.

The current tranny has over 300K and needs a rebuild anyway, so I'm not to adverse to throwing a couple of experiments at it. But I have to get the truck to run first, then I gotta make it shift.

Little bit OT, but what issues do you have with the DS4 that makes you want to swap to a DB2?

 

[Yachtcare]

Installing a reluctor ring to the output is the easiest way to make one work as that eliminates the need for the ECM to factor in the 2.72:1 low range when in 4low and allows the use of most any shift controller box. Or you can go with a custom PROM chip in your current ECM to shut off engine functions, add a TPS to the DB2, and have it work that way(you would need to retain the crank sensor for the engine speed portion).

Here's what I got to work with........

'88 vintage J code 6.2 from a G30 van. Approx 182K miles and running great when pulled from the van about 4.5 years ago. Complete with DB2 with TPS attached. I pulled the pan, inspected bearings, new rear main, and new timing set. Since it came from a van, it has short body injectors set up.

So if I understand what youre telling me correctly, I should pull the tired 4L80E, have it built, and add a reluctor ring. Pull the timing cover, water pump and serp belt system and other anciliaries from the 6.5 and fit to the 6.2. Install the pedal and cable I have on the shelf, and I should be good to go after having a PROM burned that shuts off the engine functions, and retains tranny control functions. The 6.5 had fresh injectors and glows at the first of this year, so I can swap them over as well.

Whom would be able to create such a PROM?

Sound right? or am I missing something else?

 

[great white]

Here's what I got to work with........

'88 vintage J code 6.2 from a G30 van. Approx 182K miles and running great when pulled from the van about 4.5 years ago. Complete with DB2 with TPS attached. I pulled the pan, inspected bearings, new rear main, and new timing set. Since it came from a van, it has short body injectors set up.

So if I understand what youre telling me correctly, I should pull the tired 4L80E, have it built, and add a reluctor ring. Pull the timing cover, water pump and serp belt system and other anciliaries from the 6.5 and fit to the 6.2. Install the pedal and cable I have on the shelf, and I should be good to go after having a PROM burned that shuts off the engine functions, and retains tranny control functions. The 6.5 had fresh injectors and glows at the first of this year, so I can swap them over as well.

Whom would be able to create such a PROM?

Sound right? or am I missing something else?

I don't think that will work as you expect. The PCM uses the APP sensor instead of a TPS to determine throttle postion. IF it doesn't see an APP it won't know where your throttle setting is and that will mess up your shift points. I believe Bobbiemartin tried to do it without an APP and it was not very successful.

Your best bet would be to find a TCM instead of trying to adapt a PCM. The TCM in the earlier trucks was made to work with a DB2 and uses a simple TPS on the DB2 linkage IIRC.

Now if you go with a bunch of household light switches on your dash like the chap in the youtube video, all bets are off.....that might not need any inputs at all.

Personally, I'd probably just buy and optishift (now USAshift I think), plug it in and call it a day.

 

[THEFERMANATOR]

I don't think that will work as you expect. The PCM uses the APP sensor instead of a TPS to determine throttle postion. IF it doesn't see an APP it won't know where your throttle setting is and that will mess up your shift points. I believe Bobbiemartin tried to do it without an APP and it was not very successful.

Your best bet would be to find a TCM instead of trying to adapt a PCM. The TCM in the earlier trucks was made to work with a DB2 and uses a simple TPS on the DB2 linkage IIRC.

Now if you go with a bunch of household light switches on your dash like the chap in the youtube video, all bets are off.....that might not need any inputs at all.

Personally, I'd probably just buy and optishift (now USAshift I think), plug it in and call it a day.

The OBD1 ECM can be changed over to only recognize the APP 1 side which works directly with a standard TPS's voltage range. The big cost of doing it is the custom tune whereas if he went with an aftermarket TCM like an OPTISHIFT he could adjust it himself to do whatever he wants. He could also get a chip burner and such and do his own files if he can find a definition file to do so, but the labor involved in this option may outweigh the cost savings.

 

[Yachtcare]

Well, here's an update.

There were a lot of other problems encountered on the way to the DB2 swap, some of which is chronicled in other areas of the forum.
In mid April I finally got the truck back on the road, with a Junior Moose pump from Conestoga Diesel in PA. Truck has new life with that pump, and runs great. The expense and time issue prompted me to try the "light switch" method of manual shifting the 4L80E in the manner that is shown on the you tube vid in the opening post. I removed the cup holder on the front edge of the console and mounted the switches there. The shift pattern is easy to get used to, very similar to a standard H pattern with a manual, but I can flip the switches with my index finger.

About the middle of August a rubber segment of cooler line split and I lost a lot of fluid and heated the trans. Fixed the line, put fluid in and all was well. Two weeks later I noticed the temp on the trans would start creeping upward after an hour of driving round town. Mid September, I suddenly lost 3rd and 4th, and temps hit 240 as I was about a mile from the barn I limped it back and shut down. Pulled pan, did filter and fluid change. Fluid was burnt, and there were some small metal shavings in there. But figured I'd try to get a bit more life out of it. Fluid poured thru the trash pan at the front of the tranny when I started it, so obviously the pump seal is gone.

Don't know what killed the trans, a low fluid run, running with the manual switches, or the fact that it has over 300K, most likely a combination of all the above.

As of this post, the tranny is ready to come out, but for some reason the trans will not separate from the engine. Tried some gentle heat and a liberal soaking of blaster on the dowel pins. I'll go back out in a while and see what that does.

 

[ak diesel driver]

I'd recheck to make sure you got all the bolts

 

[Burning oil]

Just an FYI: OptiShift 9th item down here http://www.leroydiesel.com/Page_2.html

 

[Yachtcare]

Yep, had all the bolts. Just took some more jiggling and cursing and out it came. Was hung up on the passenger side dowel pin. Perhaps the downpipe heat creates a bit more corrosion on that side?

Anyway, the tranny is out, and stenciled on top of it is 08-12-02 some initials and what looks like ACA Trans. So I have to assume that the trans was built once before. The only ACA trans I can find is in California. From the Carfax on my truck it was sold on Long Isl, NY and came to SW Florida 4 years later.

I'm certainly ready for an Opti Shift, the new IP is ready for an Opti Shift (the 700R4 style TPS is mounted)but my wallet isn't...... yet.
Hopefully very, very soon. Gotta see how expensive this trans build is going to be.Half tempted to try the build myself, but haven't researched what "special" tools are needed, and if I'll have access to them. That's Monday's task.

 

[Will L.]

Make sure to clean the dowel pins and holes very well. Check for the pin having been knocked out of position little. I broke a th400 tranny bell housing area from this issue many moons ago. The dowel pins were hard to find, but can be changed if bad.

 

[JayTheCPA]

How about a nice NV4500 swap???? Am looking for somebody to go through the conversion so that I can benefit from the experience :hihi: