Ok, then I will start at the trans connector. Hopefully it isn’t gonna need a rewire. The most annoying part is I bought the truck with the idea of “it has a new trans and Tcase” drove great until last august when it nuked the trans and I dropped the pan only to find lots of chunks. Now it has a new trans and loads of issues

 

So I went to unplug the connector, it was already disconnected. I plugged it back in and turned the key to the on position. Previously the trans temp and OD off light would stay in for a good while. This time they did what I would’ve expected a normal warning light to do on turn in which is flash. So this seems like a slightly good sign to me. I think whatever latches on are on that plug must’ve broken off so it popped off, because I know I connected it

 

That would certainly annoy the trans..... but, if it didn't have any connection at all, the trans would just be a 'manumatic'. Plug it in good and tight, clear the codes, and see what happens.

 

Ok so I have news, I added fluid because it had almost none in it, and I made sure the connector was right. My dad and I drove around for like half an hour and it was perfect. Hit every gear nice and smooth until it threw the trans temp and OD off light at us and started acting a little funny. I’m waiting for it to cool down a bit and then I’m gonna check that connector again because I know in the past that was my culprit when that happened.

 

What year is your truck, and what shape was the connector for the trans temp sensor? Still have the check valve in the trans cooler line?

 

Umm well, I don’t have the stock lines anymore because they were filled with metal, so I don’t have a check valve. Also the connector looked fine

 

But what shape was it? That changed over the years, and a newer sensor in an older truck will quickly disable overdrive, and then turn the trans temp light on...... Usually it happens pretty quick.

What are you doing for a trans cooler at this point?

 

Oh don’t worry, i know it isn’t the transducer, I bought a 2001 trans but was told it was a 98, I switched everything over to 98/99 wiring and sensory.
my trans cooler is just hoses run from the trans to an external cooler mounted in front of the condenser, didn’t think I needed the check valve

 

So you should have the round connector for the trans temp sensor..... Assuming that is correct, then, your trans likely IS getting hot. Which just ain't good. And no, you don't need the check valve, in fact, you REALLY DON'T want it.

How big is your cooler?? I might be tempted to install a trans temp gauge, and see what the numbers really look like.

 

The cooler is probably 8” by 12”
yes I have the round connector
what did the check valve do that anyways? I knew it always got clogged with metal