Trans install problems

[tonye96]

I just installed a 97 Mark VIII trans into my 96. I got the trans from a friends wrecked 97 that had less than 50k on it. I know that the transmission was in perfect running shape at the time of the crash earlier this year. I also installed a 99+ J mod vb and Marauder torque converter from BOC while I had the trans out. I chose to leave the lower spring out of the 1-2 accumulator for a firmer shift. The MLPS sensor was swapped from the old trans and aligned correctly.

I got it all back together and running yesterday. I drove the car for about 10 miles with no issues. Shifts were great at partial throttle. I didnt have a chance to get into it because it was raining earlier in the day and the ground was wet. I stopped by a friends house for a half an hour and on the way home, the o/d light started flasing and the car would not shift into OD. I also noticed the shifts were firmer and a bit sloppier.

Anyone got any ideas? The only thing I didnt change was the range sensor. Could this affect anything?

 

[AbrahamLincoln]

Sure a 99+ valvebody works in a 97?

 

[slowmkviii]

check fluid level

 

[Tiltedhalo]

You will need to change the EPC solenoid and the TCC solenoid, this depends on the date of manufacture on the 96 and 97, but my thoughts are your 96 has a Gen1 trans. The EPC solenoid and the TCC have different pulse width function.

 

[tonye96]

It turned out to be the gray connector on the trans. A few pins were broken and a few more fused/melted together. Replaced and all is good.

Thanks anyhow....

 

[AbrahamLincoln]

You will need to change the EPC solenoid and the TCC solenoid, this depends on the date of manufacture on the 96 and 97, but my thoughts are your 96 has a Gen1 trans. The EPC solenoid and the TCC have different pulse width function.

what does the EPC selenoid do? I'm pretty sure when I swapped the 01 into my 95 i didn't swap this over. My car runs great? I did do the TCC one though...

With this superchips chip im borrowing the shifts are really firm. I couldn't see how the jmod would with the 99+ trans with a chip. How do you like the shifts? Do you have a chip? Even took out the bottom spring! wow. my :q:q:q:qs are crazy already. If I pull the chip the shifts are smooth yet firm, with the chip they are really snappy and even chirp third once and a while.