TXjeepTJ

iTrader: (8)

Just got done rebuilding a 4l60e that was slipping in and out of 4th gear. It is still doing it. I'm starting to wonder if it is tune related as the engine has had problems relating to the tune

the vehicle is a jeep wrangler that was swapped in a 5.3L and a 1999 4l60e. The PCM is off a 99 trans-am I think and previously (due to it being a 99 PCM and it using a 2002 camaro wiring harness) the engine ran horrible and it needed to be tuned to correct the o2 sensors.

So I'm starting to wonder if it is in the computer. When 4th gear slips- it doesn't feel like a normal slip. It catches and moves and then every second or so it acts as if it goes into neutral then back into 4th then to neutral (it does this continuously when giving it throttle at 55mph +). Almost as if the torque converter is locking and unlocking.

is there a simple way to test and see if the torque converter is staying locked? I have an obd2 scan tool, but I don't think I can see if the TCC is locked or not using it.


THANKS FOR ANY HELP!

Predator T/A

iTrader: (7)

sounds like you have a servo issue not holding the band on.

performabuilt

iTrader: (25)

Well on the converter you have 2 things to monitor for TCC the TCC ENABLE and the PWM % Unless you used the transgo shift kit then the PWM is mostly eliminated. As for the TCC enable you can ties an LED in. One side to the tan wire with black stripe the other side to B+ 12 VOLTS when the TCC enables the LED should light up. (note must be and LED 12v NOT A TEST LIGHT) On the PWM you will have to find a way to look at data unless its like i said eliminated in the build. More than likley you will however find the answer in the TCC enable.

TXjeepTJ

iTrader: (8)

I'm a little confused on the wiring for the LED, do I splice into the tan/black wire and then connect a wire straight to 12v on the other side of the LED? pretty much just using the tan/black as a ground (I'm guessing when the TCC is activated it is grounded)

is the tan/black located at the brake switch or do I need to go to the plug at the transmission?

and if the LED goes off every time it slips, then it IS in the tune?

Thanks for the help

also- I hope it's not the servo/band issue, as I made sure that was correct lol

performabuilt

iTrader: (25)

Yes the wire is at the trans and yes when it goes off lockup was disabled by the tuning. the tan/blk is grounded when it on so you will want neg side of LED to it.

TXjeepTJ

iTrader: (8)

I took it to a transmission shop, he hooked up a special computer to it and pulled some codes that werent throwing the check engine light. One of them was brake switch low voltage or something. He also said that the computer isn't showing any brake signal for the torque converter. I'm wondering if the shop that installed the wiring harness didn't connect the brake switch to the right wire. Would that cause a symptom like what I described?

the transmission shop said it also might be the servo as Predator T/A menchined. Can I access/fix that without taking the transmission out of the vehicle? or do I need to have the transmission on its back to mess with it

also, the guy didn't have time to have the computer plugged in and go for a drive to see if the TCC was acting up because of the tune

thanks again guys

TXjeepTJ

iTrader: (8)

Ok guys, I plan on checking out the brake switch connection tomorrow. Hopefully that will fix it, but I'm not counting on it doing the job.

I think it might be more of a problem with the servo. As when I installed it- it was a little hard to turn the output shaft, which I think is a band thing. I've been looking up info about the servo and everything. I have one question, what does this mean

"proper band clearance is 1/16" to 1/8" " where is this measured?

The band and reverse input drum on this transmission were completely toasted when I took it apart for the rebuilt. Does this mean that whoever rebuilt it last time, didn't correct the band clearance - making the band grab the input drum too hard?

TXjeepTJ

iTrader: (8)

I think I found out how the "band clearance" is measured, is it the amount the servo cover can be pushed in once the retaining clip is installed to hold it in. If this is true, then my cover moves in 1/2" which is way too much. Any advice on what I should do?

GregWS6&z28

iTrader: (8)

^ you are right on the clearance. I'm not sure how it can actually be measured though. Use the guesstimate gauge? If it is a 1/2" it sounds to be waaay too much. Sounds like maybe the servo "pin" tip may have worn out.

my built 4L60E did the same thing, servo clearance opened up. I added a washer to the servo to make up some pin-to-band clearance and it worked a little while longer. I was feeling lucky one day and added another washer and while I was driving ended up breaking the transmission case at the servo bore. You can tighten up the clearance, but I recommend just having a shop rebuild it.

TXjeepTJ

iTrader: (8)

I wired up a new brake switch, I checked the one that was installed on it from the shop that did the engine swap- and the transmission was NOT getting 12v when the brake is not pressed in. I wired up a new switch and took it for a test drive and it didn't seem to slip at all in over drive

Could the brake switch have been the problem? would it cause something similar to slip on and off on and off in over drive?

TurbopigB4C

iTrader: (5)

Did you make sure during your rebuild that the valve body spacer plate was not worn where the check ***** sit. There is one that wears really bad and I think it will cause a slip in overdrive. There is also a few other check ***** in the case and in the input drum that can get worn and cause slippage. I wouldn't think that the brake switch with no power applied would cause the converter to give erratic converter application. Hopefully its fixed though I rebuilt mine at the same time as you and I know how it feels to have so much time and effort into something you don't know is going to work.

TXjeepTJ

iTrader: (8)

Yeah, the holes didn't look too beaten up. I even took it to a transmission shop to get a 2nd opinion on them

I know what you mean as the brake switch wouldn't seem like it would really be the problem, a couple posts up I was saying how it most likely will not be it because it just seems too much of an easy fix lol plus how it only does it in over drive is fishy

and yeah, it sucks going through the pain of pulling the transmission, rebuilding it and installing it back in and it still be doing the same thing!

plane.qc

I have had this on-going problem with my 99 Camaro and what I have discovered is that disconnecting the battery for an hour and reconnecting it makes the problem go away for about 2 weeks. Then it occasionally begins displaying symptoms and progressively gets worse over a weeks time. Disconnect the battery again and the cycle repeats itself. I suspect this has something to do with the force motor, or pressure control solenoid as it is also known. Next step is to Ohm out the circuits from the harness connector at the PCM and look for high resistance indicating a corroded or bad connection. If that doesn't work, I am going to have the PCM re flashed. In my mind, if the problem were mechanical it would do it all the time.