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Richard
Richard, Dodge Technician
Category: Dodge
Satisfied Customers: 4139
Experience:  Over 24 years of experience as lead tech and shop foreman.
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My 99 Dodge 1500 will not shift in to overdrive.

Customer Question

My 99 Dodge 1500 will not shift in to overdrive.
Submitted: 5 years ago.
Category: Dodge
Expert:  Richard replied 5 years ago.

Hello and welcome to Just Answer!

The o/d is electronically controlled and usually when there is a problem it will set a fault code in the PCM. Have you checked the PCM for fault codes?

Customer: replied 5 years ago.
yes, I have tried that. What else do you think it could be? Do you think it could be a solenoid, a senser, or the torque converter?
Expert:  Richard replied 5 years ago.
There are no codes??
Customer: replied 5 years ago.
Here are the codes I have: 0123 and 1495
Expert:  Richard replied 5 years ago.

Fault code P0123 will affect it from shifting into o/d. This code sets when the throttle position sensor signal voltage goes high. This could be cause by the TPS, wiring problem or a PCM issue.

 

Have you replaced or checked anything yet besides the oil and cable?

Richard and 3 other Dodge Specialists are ready to help you
Customer: replied 5 years ago.
I put a new throttle positioning sensor on it, checked the wiring, and reset the computer. It's still not shifting into 4th gear. What else do you think it could be?
Expert:  Richard replied 5 years ago.

Is p0123 fault code still setting after you have replaced the tps and disconnected the battery?

Customer: replied 5 years ago.
no
Expert:  Richard replied 5 years ago.

Sorry for not getting back to you sooner, I fell asleep last night. I am a full time tech during the day and will be online after work, so I will get back to you then.

Expert:  Richard replied 5 years ago.

Do you have access to a scan tool? I would like to know if the PCM is allowing o/d. If the PCM shows allowed, that means it's commanding o/d and the problem is from the PCM to the o/d solenoid, or an internal transmission problem. It could be the PCM, wiring problem, o/d solenoid or internal failure. If the PCM shows the o/d is not allowed, then there has to be an input to the PCM that isn't working properly.

 

Does the transmission have 1st, 2nd and 3rd gears?

 

Do you know what the engine rpm is when traveling 60 mph?

Customer: replied 5 years ago.
No, I don't have access to a scan tool. The truck shifts perfect in 1st, 2cd, and 3rd gears. When traveling 55- 60 mph it runs about 5500 RPM. I did hear a thump from under the truck about an hour before this problem started, I didn't think much of it untill now.
Expert:  Richard replied 5 years ago.
5500 RPM at 60 mph? Did you mean 2500?
Customer: replied 5 years ago.
No, 5500 rpm at 60 mph.
Expert:  Richard replied 5 years ago.

Then it can't be shifting into third or overdrive. The RPM is extremely high at 60 mph and I am not sure what the RPM would be if it stayed in second. I don't think the RPM would be that high even if it stayed in second but I would like you to try and see if it feels the same if you drive it in manual second. Pull the shifter into manual second and let me know if it's the same.