I bought this truck ('99 w/ auto) knowing it's got gremlins, but got it for really cheap. At first the lighting wasn't working properly. I tracked it down to being a bad blinker switch and GEM. Now that I've swapped that out, all my lighting issues are resolved. HOWEVER...now the thing is shifting REDICULOUSLY hard. I've tested it by really gently easing into the gas and even letting off when I want it to shift, and it does...but still just as hard. It was not doing this before.
Does the transmission have a separate controller or does it use one ECM shared with the engine? Would it be tied in with the GEM, and needs time to 'learn'? I don't want to shell my drive train on top of everything else.

Thoughts?

Thanks!

 

The PCM controls both the engine and transmission. There is no learning in the system at all. You need to see if any codes are stored.

 

It's only shifting like this after doing that other stuff? Can you put the original GEM back in and see what it does?

 

The original Gem was toast. I actually think the original issue was just the blinker switch. But while trouble shooting with my power probe, I fried it on accident.

 

Ah... I know it really has nothing to do with it, but did you check all the fuses?

Is the OD-off light flashing, and does it work in the first place?

 

I will recheck the fuses, I did check them during the troubleshooting of the original gremlins. But I won't rule that out at this point.

The OD button isn't flashing and works fine. That was one thing that I did check.

One other thing that I just thought of, the stall appears to spin pretty high when taking off, even if I'm tender footing it. Or maybe my minds eye is emphasizing it due to the issue...I don't know. But taking off, it seemed to spin up to about 3K before engaging, and it hits hard.

 

That's usually a sign of a dead transmission.

 

LOL...you're just FULL of good news!

I'm not real convinced that it's 'dead', because it shifted just fine the day I parked it. The last time I drove it I temporarily got around my gremlins by putting a jumper wire on the tail lights to give me brake lights. I drove about 40 miles round trip to pick up a slide in camper. It shifted smooth 100% of the time. The only problem it had was no tail lights/blinkers. It gets parked, 'rewired', and now it's shifting like a drag car. I won't rule it out by any means (ugh).

 

Ok, this dang thing is gonna have me in the funny farm soon.
I checked the fluid...good. DIRTY, but full. Definitely time for a trans service.

I individually checked every fuse, and also tested every relay in both the engine and under dash panels. Everything was good. I got out the mechanic stethoscope, as I recalled hearing a quick clickity click behind the dash, in the area of the stereo. When I turned the key over, no sound. Hmmm...

I decided to take it for a test drive and carefully note it's exact behavior. It shifted PERFECT every time. Not that I'm complaining, but C'MON!!

Then I noticed that it's losing antifreeze fast now. THAT'S NEW!... It was pooling up on top of the intake manifold. Know that out of habit, anytime I pop the hood, I just naturally take note of the coolant level of any vehicle. The other day when I wrapped up the wiring issue, I reconnected the battery and the fluid was only about 1/2" from the full cold mark. After the drive tonight, there was only like 2" of coolant from the bottom showing. Along with the dribble trail down the culdesac. I had my son alternating throttle while I looked and I couldn't see it leak anywhere. Time for a leak test.

 

That's weird that it shifts OK now... maybe something you checked had a bad connection and now it's solid?

As for the coolant, it's on TOP of the intake, or it's down in the valley under the intake? There is a crossover pipe that runs from the back of the water pump to (I think) the back of the intake. That pipe is known to rot out, or the piece of hose that connects it to the water pump and intake rots.

 

Thanks! That's actually 'good' news. I was beginning to worry that it was something really serious! I am noticing it pooling up big time just to the right of the front on the passenger side head. Hard to explain. I'll just post a picture tonight. I was trying to google the cross over hose. Is that what it's actually called? I found nada.

Thanks!

 

Bypass? Something like that.

 

Ok, here's where the fluid is most visible. Just behind and below the alternator.

 

Is it coming from the intake manifold where it mates to the head?

 

That I can't tell. To me it looks more like it was splashed up there, rather than leaking. But ya never know.I just know it went through a LOT very quickly.