Help With Tranny Trouble

[Jacques]

92 Chevy Silverado

Originally 350 engine, now changed to 305

3 speed auto with overdrive

Supposedly a "shift kit" in it

 

Lots of miles - bought the truck with a busted odometer, and it reads about 150,000+ miles

 

When I bought it, the tranny shifted a "little" hard, but I was told that was because of the shift kit. I bought and installed an AEM cold air intake that came with a 1" TB spacer. After the cold air intake install, shifting was now at a silly high RPM. I eventually discovered that the kick down cable was too tight, causing the tranny/ECM to think the throttle was open a lot more than it really was. I disconnected the cable, and drove it like that for 4-5 months (I now realise that this might not have been a good idea).

 

The other day, 3rd and overdrive stopped "driving". It'll run fine in 1st and 2nd, but as soon as the vehicle speed is high enough to shift to 3rd, there's no drive. It's as though the tranny is in neutral. I tried running it with the kick down cable reconnected, and the shift points go up higher like they did before, but the drive is gone in 3rd and OD. I'm guessing that the dropped line pressures from running the tranny without the cable connected have lead to some sort of internal failure. I'm wondering if this is something the can be fixed through the bottom of the tranny (pan) or if I should just take the tranny out and bring it to the transmission shop for repair.

 

On another note, when the previous owner changed from the 350 to the 305 motor, they did not change the ECM. The chip has "AWLB" code on it. I'm told by the boys at Superchips that this is the code for the 350 programming, but that it should be fine fo rthe 305 motor. I have my doubts, and would like to try a chip specific to the 305 motor.

 

Thanks for reading, and here's hoping its nothing too serious.