4l80e question
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4l80e question I have a '93 Jeep Wrangler that I just put a 6.0 and 4l80e into. I used a Howell wire harness (don't get me started on that) 
I just got her up and running a few days ago and when I'm driving, after I'm going over 20-30mph sometimes, the tranny seems to just lose any connection w/ the motor and the motor will rev, like it's in neutral. Then when I slow down, it'll grab again and go for a few seconds only to start slipping again. Sometimes it'll shift out to OD and run fine, then start to freewheel.
The tranny dipstick indicates that it has enough fluid, could I have air trapped in the system? Is there a proper way to bleed the air? I did have to completely refill it. Could I have a blockage in a line?
The harness has 2 VSS sensors and the one big grey plug that go to the tranny and Tcase, that's it. Would not having the other connections used cause this?
Thanks for any help,
Glenn
I just got her up and running a few days ago and when I'm driving, after I'm going over 20-30mph sometimes, the tranny seems to just lose any connection w/ the motor and the motor will rev, like it's in neutral. Then when I slow down, it'll grab again and go for a few seconds only to start slipping again. Sometimes it'll shift out to OD and run fine, then start to freewheel.The tranny dipstick indicates that it has enough fluid, could I have air trapped in the system? Is there a proper way to bleed the air? I did have to completely refill it. Could I have a blockage in a line?
The harness has 2 VSS sensors and the one big grey plug that go to the tranny and Tcase, that's it. Would not having the other connections used cause this?
Thanks for any help,
Glenn
I have the 80E and didn't do anything special to bleed it, and it had maybe 2 quarts in it from Hughes. I know the TC was empty, too.
How are you checking your fluid? Do you have a stock dipstick or not? How are you controlling the tranny? What fluid?
Jim
How are you checking your fluid? Do you have a stock dipstick or not? How are you controlling the tranny? What fluid?
Jim
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I'm using the factory dipstick, the stock PCM is controlling the tranny, and I'm using dexron3 fluid. It's not throwing any tranny codes, though maybe I haven't driven it enough, I've only gone a few miles because I'm afraid to get stranded.
One thing, the rear VSS is hooked to the transfercase, but the sender is the stock one on a 95 model Tcase with a reluctor ring installed, and the Tranny and tranny VSS are 2000 models. Is it possible that the older sender isn't playing well with the newer one?
One thing, the rear VSS is hooked to the transfercase, but the sender is the stock one on a 95 model Tcase with a reluctor ring installed, and the Tranny and tranny VSS are 2000 models. Is it possible that the older sender isn't playing well with the newer one?
It's definitely possible that the sensor is not playing well. It might be a good enough signal not to throw a code but not good enough to work right. I would check the P/Ns with a GM parts man. If they don't match, replace it. Hopefully the right sensor will fit in your transfer.
You are checking the fluid when the tranny is hot, in Park, right? And you've cycled the shifter through all the gears & reverse with the engine running? Stock dipstick?
Jim
You are checking the fluid when the tranny is hot, in Park, right? And you've cycled the shifter through all the gears & reverse with the engine running? Stock dipstick?
Jim
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Okay, it was the sensor. I can't use a later VSS in the Tcase, wouldn't fit. I put another VSS into the rear of the tranny though, it now has two, and it shifts perfectly!! Guess it will play hell with the speedo when I put it in 4 wheel low though, but at least it runs. 
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Originally Posted by DeltaT
It's definitely possible that the sensor is not playing well. It might be a good enough signal not to throw a code but not good enough to work right. I would check the P/Ns with a GM parts man. If they don't match, replace it. Hopefully the right sensor will fit in your transfer.
You are checking the fluid when the tranny is hot, in Park, right? And you've cycled the shifter through all the gears & reverse with the engine running? Stock dipstick?
Jim
You are checking the fluid when the tranny is hot, in Park, right? And you've cycled the shifter through all the gears & reverse with the engine running? Stock dipstick?
Jim
I have the deep pan and a long loop ready for a tranny cooler, and my 4L80E took like 15 quarts before it showed as properly filled on the stock dipstick. I was looking for puddles but that's what it needed at the beginning... My torque converter does not have a drainplug so it will retain at least 1.5-2.5 quarts at a service change.
Run it as little as possible to cirulate the fluid until it registers on the dipstick, then run it through all the gears and reverse. Take it out for a drive until it is warm, and top it off as needed.
Jim
Run it as little as possible to cirulate the fluid until it registers on the dipstick, then run it through all the gears and reverse. Take it out for a drive until it is warm, and top it off as needed.
Jim
thanks for you're help, i found the problem, the shift actuator was positioning the lever between shifts, instead of being in park,when it said in park it was not quite in. i just bent the bracket so it went completely in park,and everything worked,i did add 3 more qts of fluid to allow for the deep pan, thanks
