Just wondering, how can i adjust the TCU on my 93 legacy wagon? Like adjust how the AWD acts, like 50/50 ot 40/60 or 60/40 something like that, and adjust the first gear shift point. Thanks, oh and if possible, how to reset to factory settings.

Simple answer is you can't adjust anything on the TCU.

 

Some people have put a switch, or potentiometer in the duty c solenoid wiring to force 50/50 torque split....but I'd be cautious about how you do that.

Simple answer is you can't adjust anything on the TCU.

 

Some people have put a switch, or potentiometer in the duty c solenoid wiring to force 50/50 torque split....but I'd be cautious about how you do that.

 

Really? THats funny, because my car used to shift at 6500RPMS and now after the tranny shop touched my car it shifts at 6200RPM. Is that normal? how did he do it.

Did it always shift at 6500 rpm? If so, something was wrong. If you hold the pedal to the floor it should shift at 6500 rpm.

 

I'm not sure what the tranny shop did, but I would say it's not normal.

Did it always shift at 6500 rpm? If so, something was wrong. If you hold the pedal to the floor it should shift at 6500 rpm.

 

I'm not sure what the tranny shop did, but I would say it's not normal.

 

THe tranny shop seemed like a bunch off liers, but they pretty much rebuilt the tranny and got a new TCU because my old one would not allow the tranny to shift when i floored it.

They may have:

Changed torque converters, added a shift kit (they are available for the 4eat transmissions and they do a great job of moving the shift points, making it shift harder/firmer) or changed gear ratio.

Really? THats funny, because my car used to shift at 6500RPMS and now after the tranny shop touched my car it shifts at 6200RPM. Is that normal? how did he do it.

Shifting at 6200 would seem a little bit better to me...you're still way past the torque range....

 

I can get my car to bounce right off the 6500 marker if I wanna drive it up there. The TCU is a computer...it's not something you can...switch. You can switch the solenoid C to change bias between the back and front (50-50 or normal pretty much), but solenoid C has absolutely nothing to do with shifting at 6200 or 6500. Still don't know why you would want to change the shift point...under power mode, I think the shift map is perfectly fine. Shifting at 5500 is just about the right place because of the torque band.

Often when a tranny is rebuilt the shift point can change. This is becuse the clutches are now at maximum thickness and although the shift is triggered at the same time the engagement point changes.

They may have:

Changed torque converters, added a shift kit (they are available for the 4eat transmissions and they do a great job of moving the shift points, making it shift harder/firmer) or changed gear ratio.

 

Hey you know what, these guys changed my torque converter 3 times!!! they told me it cracked, or something like that.

It sounds like they were having a bad time with your car. Most of the times jobs go well but when they go down the tubes they seem to snowball.

It sounds like they chased the problem on your car and just kept changing parts until they got it to work.

It sounds like they were having a bad time with your car. Most of the times jobs go well but when they go down the tubes they seem to snowball.

It sounds like they chased the problem on your car and just kept changing parts until they got it to work.

 

Yeh they figured it was the TCU does that make sense?

That was probably the last thing they changed and it finally worked. It does make sense but you never know if it was the problem in the first place. When they swapped trannies they may have needed the TCU that came with the tranny to get it to work right. Your car was probably a fiasco for those guys.

I'd like to say I have not been there but I have. After you finally get it to work you usually find you expended five times the effort you needed to.

I once changed a bus muffler in Oakland and the bus overheated on the Bay Brigde to SF. I figured it had to be a deffective muffler and put the old one back on. It still overheated and I started pulling everything else apart from the thermostat, 300 lb radiator, the 100lb shutters, etc.

I finally found the water pump drive had just happened to shear off on the trip back. Then I got to put it all back together including switch the muffler again. If the muffler had not weighed 200 lbs and been behind the engine in a Greyhound bus it might have been easy.

When a job goes to%#@& it really goes to *^#@!

Shifting at 6200 would seem a little bit better to me...you're still way past the torque range....

 

I can get my car to bounce right off the 6500 marker if I wanna drive it up there. .. Shifting at 5500 is just about the right place because of the torque band.

 

The thing though is that this is an automatic. At full throttle you get torque multiplication through the torque converter , so the car still is going to pull all the way to redline. I know that's the one thing I miss about my automatic when compared to the MT.