kelsey_canard

iTrader: (6)

My truck has been acting real weird after I installed my converter. It has been in for maybe 100 miles. It feels like the tc clutch is locking at a stop in gear, or something is binding and dragging the motor down. I can only brake stall to ~ 1800rpms when this happens, and the truck wants to drive itself. Reverse is more noticable. When I am in drive, the problem will come and go. Seems to always be there in reverse. Fluid has a hint of burnt smell now. Wot and 1mph up seem fine. Does anyone have any ideas of where to start? I have hptuners, and can log anything necessary.

Also, I am running a 4l60e tune with the 4l80e wiring swap. Still on the 4l60e segment. I can post a tune and logs if necessary, but just looking for general ideas of where to start looking.

kelsey_canard

iTrader: (6)

Bump. Any ideas?

AintQik

iTrader: (3)

So first off I'm no expert but I've been shooting a prioblem on my car and got all kinds of dumb stuff in myh head.

If you have HP I would log all the trans status stuff and see what is going on. You should see the TCC and PWM engaging and whatnot. With your wiring, not sure how that is going to work out for you, but if it was working before I would start there. Find out if the computer is commanding anything wierd, or its internal to the trans.

kelsey_canard

iTrader: (6)

Ok I did a quick trans pressure test. Im sure everything was moderately cold since it sat while I got the tool ready. I just really quickly checked park, neutral, and all forward gears. They were right around 45psi. Reverse was around 90. I swear I saw the pressure drop down to 0 right after my first start in park. Not for sure. Did everything really quick, with the truck on jackstands.

Also, I cut the wire that controls the tc solenoid to lock on my trans harness. That should have ruled out anything in my tune.

Any input?

mrvedit

What brand/model converter?
Was it new or used?

Sounds like your converter is bad with a dragging lockup clutch. I experienced exactly the same symptoms when I ruined a converter due to one of my not-immediately-successful transmission experiments.

kelsey_canard

iTrader: (6)

Converter is a brand new ptc 10" single disc. 3000 stall.

mrvedit

I don't know how the 4L80E seals the TCC lockup circuit, but during one of my experiments with a 4L60E pump mod, I created a leak in my circuit, causing the lockup clutch to first slip and then drag. Obviously you didn't mod your trans, but perhaps the converter installation caused a leak.

A 4L80E expert really needs to chime in here.

kelsey_canard

iTrader: (6)

X2. Im not much of a trans guru. I'm downloading a rebuild manual now. Maybe I can educate myself enough to make a diagnosis that in the ballpark.

kelsey_canard

iTrader: (6)

Well I got some more data for those still willing to help. I did notice that during the whole test I could hear a rattle around the torque converter area. When the rattle happened, the engine stumbled and line pressure would fall 5 or 10psi. No idea on trans fluid temp for the first test. Probably took 5-10mins

////ELECTRONICS UNHOOKED////
Park at 1200rpms - 165
Park at idle - 75
Manual 1st at idle - 80
Manual 2nd at idle - 80
Manual 3rd at idle - 80
Manual 4th at idle - 80
Manual 2nd at 1200rpms - 140
Manual 4th at 1200 rpms - 140
Manual R at 1200rpms - 140

////ELECTRONICS PLUGGED IN(108* trans temps at this point)////
Park at idle - 35/40
Reverse at idle - 35
Manual 1 at idle - 30
Manual 2 at idle - 30
Neutral at 1200 - 45/50
Reverse at 1200 - 75/80
Manual 1st at 1200 - 45
Manual 3rd at 1200 - 45

////ADJUSTING FORCE MOTOR CURRENT IN SCANNER (temps at 135)////
750ma at idle - 50
500ma at idle - 50
0ma at idle - 50 (temps at 140)

kelsey_canard

iTrader: (6)

Well the next series of data looks promising. I estimate the trans temps to be between 100-125* in the test.

////ELECTRONICS UNHOOKED AT 1500 RPMS////
Park - 170
Reverse - 220
Neutral - 170
Drive - 180/190
Manual 3- 170/180
Manual 2-170/180
Manual 1-170/180

hotrodth

My converter is doing same thing. I have a jakes performance converter. As soon as it is in drive its feels like its dragging. On the trans brake itll only go up to 2000. Suppose to be a 3-3300 I assume its just too tight. But I may have a issue like yours. I had hpt do a segment swap for me though.

Intrested in what you find.

braiden1

If all pressures are good and pump condition is well, then a few pump modifications can fix this condition. The first is the common line to lube modification that will allow line pressure to feed the converter limit valve. Second mod is to the converter limit valve, some converter companies supply a heavy spring for this mod on multiple disk billet converters.