2001 won't shift from 1st to 2nd...try aftermarket Gov Solenoid?

[Devil Black Diesel]

My truck stopped shifting from 1st to 2nd yesterday. It's a 2001 auto 4x4 with a DTT trans. If i get on the gas from a stop in 1st gear and accelerate to about 25mph, then let off, then get slightly back on the pedal it will sometimes shift into 2nd. When I'm able to get it into 2nd, it will shift normally to 3rd/4th and downshift properly. But from a stop it will never shift from 1st to 2nd gear.

I read another thread where some guys swapped the $20 trans output speed sensor and it fixed the problem, so I will start with that for process of elimination. But if that doesn't work has anyone tried this aftermarket kit?

Suncoast 618-GK Governor Pressure Solenoid Upgrade & BD Diesel Pressure Transducer Upgrade

https://www.thoroughbreddiesel.com/...a75KD7oW91Aq6rX7NW5-3h0rQ6zwh4ZhoCtDoQAvD_BwE

The guy in this video suggests doing the same. Is it safe to say the stock stock governor solenoid and pressure transducer aren't ideal for handling the higher pressures of an aftermarket trans?

 

[Ozymandias]

Go into Low Range and try if it does the same.
When the output speed sensor is gone (it often does) it will rev very high in every gear till it upshifts.
The sensor itself is magnetic, means it collects lots of debris on its body that also doesn't help.

The DNJ governor and transducer is a nice upgrade anyways, I've done it on purpose.

 

[Devil Black Diesel]

Is the "DNJ" governor and transducer the one I linked above? If not, can you please link it?

 

[Ozymandias]

It's this one, more or less the same but with the Rostra pressure transducer instead of the BD one.

https://transpartsnow.com/42-46-47-...upgrade-w-gm-solenoid-and-transducer-2000-up/

We had some people with problems here with the BD unit.
Safes you a lot of money.

 

[Devil Black Diesel]

It's this one, more or less the same but with the Rostra pressure transducer instead of the BD one.

https://transpartsnow.com/42-46-47-...upgrade-w-gm-solenoid-and-transducer-2000-up/

We had some people with problems here with the BD unit.
Safes you a lot of money.

Okay, I'll go with that one if you suggest staying away from the BD unit.

BTW, will I get a ATF bath when I change out my speed sensor? I'm going to do it in the AM. Just wondering how much of a mess it will create.

 

[Cummins12V98]

At 150k my DTT would not shift out of first. Towed it up to Bill and he said it bled to death internally, NOT happy. 4k later new trans, GRRRRR.

 

[Ozymandias]

Okay, I'll go with that one if you suggest staying away from the BD unit.

BTW, will I get a ATF bath when I change out my speed sensor? I'm going to do it in the AM. Just wondering how much of a mess it will create.

No, just a couple drops seeping out.