Glamissand1
New member
Im trying to figure out what year the cherokee auto trans went to a lock up torque converter. I would also like to know if there was a good year or make to swap out without having to change the ecm.
Cherokee Auto Trans
- Thread starter Glamissand1
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MudderChuck
New member
I think they all had lock up converters. My guess from your header is you are looking for a transmission for your 88? Some issues with using a after 90 transmission in a 87-90 Cherokee. The plugs/connectors are different, somewhere down the line they changed the neutral safety switch and after around 96, they changed the speed sensor. The TV cable also changed for the HO type motors.
I've heard of guys swapping in as late as 98 into a 88, rewiring the transmission (from the solenoids out), replacing the neutral safety switch, TV cable and speen sensor (with the early type). Never done it myself.
If your looking for something without a lock up torque converter, that's easy. Cut a switch into the AW4, lock up solenoid wire.
I've heard of guys swapping in as late as 98 into a 88, rewiring the transmission (from the solenoids out), replacing the neutral safety switch, TV cable and speen sensor (with the early type). Never done it myself.
If your looking for something without a lock up torque converter, that's easy. Cut a switch into the AW4, lock up solenoid wire.
Glamissand1
New member
The issue actually is the torque converter doesnt lock up. I want to regear but i would loss mpg like crazy. Being an 88 im not sure if it should have a lock up torque converter or not.
MudderChuck
New member
The torque converter lock up and unlock is pretty mild, actually hard to notice.
I'd strip back a little insulation off of the white wire with a stripe coming out of the TCU (behind the knee kick panel under the dash, passengers side). and hookup a simple trouble light, it's 12 volts and will light the bulb when the lock up solenoid activates. If it never activates, you can troubleshoot backwards, if it does light up but doesn't lock up, it's likely the solenoid. The solenoid is a lot easier swap than a transmission.
Could be as simple as a faulty brake switch, this switch unlocks the lock up solenoid.
I'd strip back a little insulation off of the white wire with a stripe coming out of the TCU (behind the knee kick panel under the dash, passengers side). and hookup a simple trouble light, it's 12 volts and will light the bulb when the lock up solenoid activates. If it never activates, you can troubleshoot backwards, if it does light up but doesn't lock up, it's likely the solenoid. The solenoid is a lot easier swap than a transmission.
Could be as simple as a faulty brake switch, this switch unlocks the lock up solenoid.
Glamissand1
New member
Thanks for the info, is that for pre 90's?
MudderChuck
New member
For a 89 I believe, but no difference I know about, I also have an 88.
Glamissand1
New member
my hanes manutal shows 91 and later with the tcu, but not 87-90. I gather ill have to go looking for this box. If so im going to make a manual switch to lock it up.
MudderChuck
New member
TCU for the 88 is under the bottom curved part of the dash. Kind of under the glove box.
Check your PM
If you manually switch it to lock up, it will stall the motor when you stop. I'd try hooking up a simple light first and take it for a drive. Positive wire to the lock up solenoid wire, then to a small 12 volt bulb, then to ground. Could be an open circuit or even the brake switch. When the bulb lights up, you know to feel for the lock up.
When mine locks up it is pretty mild, sometimes I notice, sometimes I don't.
I most times now check out the connectors, then the wire then whatever module or sensor is suspect. Pain in the arse, but in the long run often saves a lot of money and disappointment. Last time I had my TCU unplugged, I found a few of the pins in the connector that were backing out of the plastic part of the connector. Shoved them back in there, cleaned up the contact surface of the pins real good. Poor conductivity through the connectors and pins is a pretty standard failure in the Renix models. I most always look at the connectors first and clean them for anything electric. The grounds are another hot spot. I use a good high quality contact spray (not spray oil or WD-40) and scrub on them a little whenever possible.
Check your PM
If you manually switch it to lock up, it will stall the motor when you stop. I'd try hooking up a simple light first and take it for a drive. Positive wire to the lock up solenoid wire, then to a small 12 volt bulb, then to ground. Could be an open circuit or even the brake switch. When the bulb lights up, you know to feel for the lock up.
When mine locks up it is pretty mild, sometimes I notice, sometimes I don't.
I most times now check out the connectors, then the wire then whatever module or sensor is suspect. Pain in the arse, but in the long run often saves a lot of money and disappointment. Last time I had my TCU unplugged, I found a few of the pins in the connector that were backing out of the plastic part of the connector. Shoved them back in there, cleaned up the contact surface of the pins real good. Poor conductivity through the connectors and pins is a pretty standard failure in the Renix models. I most always look at the connectors first and clean them for anything electric. The grounds are another hot spot. I use a good high quality contact spray (not spray oil or WD-40) and scrub on them a little whenever possible.
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Glamissand1
New member
Thanks for the help and information.
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