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4l80e stand alone

Also, my other question is decelerating. Does the torque stay locked and act as a retarder with any of these controllers?
Think 12000 to 13000 on a 8-10% grade for 3 miles.
 
natemc said:
Also, my other question is decelerating. Does the torque stay locked and act as a retarder with any of these controllers?
Think 12000 to 13000 on a 8-10% grade for 3 miles.
Click to expand...

I know with the one i have you can hook up a switch (pre wired, just connect a switch) to manually lock the TC whenever you want
 
natemc said:
What about the need to update the pre 96 electrics?

What kind of temps do you see on long pulls in 2nd?
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My 4l80e came out of a 95 K3500. Its been a couple years since I messed with programming but I believe you can activate the torque converter on coasting. There's so many things you can change it's hard to keep track.

I'm kinda overly sensitive about trans temps so I have the biggest cooler I could find. As long as I can get the torque converter locked, temps stay below 190 even on a long mountain pull.
 
The primary reason I went with USShift is because it can be programmed for dual dual transfercases. I can program it for 2/4Hi, 4Lo1, 4Lo2, and 4Lo3.
 
Took a trip this weekend and messed around with the software for the US Shift controller so I can confirm a couple things.

The torque converter does hold on a downhill deceleration to help with engine braking. There's a setting in the software that will allow you to adjust a boost in the line pressure for this purpose as well.

The access road to the trail started with about a 5 mile slow, switchback climb. I wasn't running much more than 15mph. I could hold 2nd gear with the torque converter locked and the trans temp never got above about 170F to 175F. Normal cruising on flat land and no load is about 165F.
 
mrk5 said:
Took a trip this weekend and messed around with the software for the US Shift controller so I can confirm a couple things.

The torque converter does hold on a downhill deceleration to help with engine braking. There's a setting in the software that will allow you to adjust a boost in the line pressure for this purpose as well.

The access road to the trail started with about a 5 mile slow, switchback climb. I wasn't running much more than 15mph. I could hold 2nd gear with the torque converter locked and the trans temp never got above about 170F to 175F. Normal cruising on flat land and no load is about 165F.
Click to expand...

What do you think you were weighing?
 
So, my trans temp is hovering around 225-230 taken at the pressure port.
Where is your temp sensor?
 
My truck weighs 8100 according to Cat Scales. My temp sensor is in the cooler line just before it enters the radiator..

The controller also reads trans temp, but I have the default display set to show me what gear I'm in. On one trip to South Dakota towing our 5000lbs camper on mostly flat and moderate hills, I had the controller showing temperature so I could compare with the pressure port temperature. They were pretty close. If I remember correctly the temperature on the controller would be a 5 to 10 degrees higher when we were pulling an uphill grade. But for the most part they were pretty similar numbers.

I'm going to be heading out camping tomorrow pulling the camper up into the Rockies on much steeper grades. I will let you know what I observe.
 
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mrk5 said:
The access road to the trail started with about a 5 mile slow, switchback climb. I wasn't running much more than 15mph. I could hold 2nd gear with the torque converter locked and the trans temp never got above about 170F to 175F. Normal cruising on flat land and no load is about 165F.
Click to expand...

Haven't really dealt with 4l80s, is there any concern with destroying the torque converter clutch while locked with heavy loads?
 
dyeager535 said:
Haven't really dealt with 4l80s, is there any concern with destroying the torque converter clutch while locked with heavy loads?
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Not really sure what it's going to do. My trans builder is going to build a triple torque for me at cost because he is interested in knowing what it will handle.
 
Will definitely be interesting to find out. I'm guessing GM did a pretty good job on the 4L80E TCC, so maybe being locked under heavy load isn't a huge deal within reason.
 
More to add after pulling the camper over the continental divide a couple times.

The auto meter guage in the pressure port reads about 10° warmer than the controller. It also rises quicker when the truck starts climbing a grade. As it stabilizes, the temps stay about 10° apart.

Couple of the steepest grades I had to run in 2nd gear with the torque converter locked. With 37s and 5.13 gears it was about 38-40mph at 2700rpm. I think I would do better with 4.56 axle gears because I could hold 2nd gear but the speed would be higher for the rpm.

I basically just hold 2700rpm because I don't want to rev the motor higher for an extended period. I could run it up and potentially shift into 3rd, but it would fall on its face. It makes me realize how much better a 6 speed trans is.

The highest temperature I saw was at the end of the 2nd gear climb and the trans was running 190°. The normal temp was around 165°.

dyeager535 said:
Will definitely be interesting to find out. I'm guessing GM did a pretty good job on the 4L80E TCC, so maybe being locked under heavy load isn't a huge deal within reason.
Click to expand...
I naively hadn't thought about it. My torque converter came from @Greg Ducato.
 
I'm no where near that temp. 220* at the pressure port regularly on incline. 200* just rolling easy
 
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