I have a 99 3500 24V with 245K miles. The other day I was leaving work and the truck would not come out of 1st gear. I drove it 20mph to the next town and stopped to refuel as I was almost on empty. After I filled the fuel tank and restarted the truck it shifted just fine. Now if I let the truck get down around an eight of a tank it will do the same thing. I did a search and looks like I’m going to try the speed sensor. Has anyone had a problem like this or have any ideas? How can the fuel level cause a shift problem?

 

You mean your rpm will go up but won't go into 2nd, or there's not enough power to get out of 1st?

 

The rpm is fine. There is no problem with power it just will not shift into 2nd

 

You have a pile of miles and I would bet your transmission bands are loose. In cold weather the oil level will be too low with loose bands and the truck will hang in first gear. Once the oil warms the level rises and all is well.

Another likely cause is that one end or the other of your throttle valve cable has popped. Check both cable ends and the housing locks, and the cable adjustment.

Lastly, and perhaps first, the throttle position sensor may be dirty or failing. That will cause low impedance and keep the electronic governor from releasing. However, this will usually impact OD and the lock-up before it ever results in failure to get out of first.

 

I got the truck with 165K and it had the Lock-up problem that is common on 99s. I had the system flashed but it was to late and had to have the Xmsn rebuilt and replace the TC. I have been driving it for about three weeks with this problem. It shifts great as long as the fuel level is above 1/4 tank. I'll check the cable and position sensor.