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sprinkles08, ASE Certified Technician
Category: Transmissions
Satisfied Customers: 22676
Experience:  Chrysler/Dodge/Jeep master tech ASE Master and Advanced Certified, Chrysler/Dodge/Jeep Master Certified, Trans Specialist
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I have a 1999 dodge 2500 5.9 cummins 4x4. The transmission

Customer Question

I have a 1999 dodge 2500 5.9 cummins 4x4. The transmission shifts fine from first to second and second to third but will not go past third.
Submitted: 1 year ago.
Category: Transmissions
Expert:  sprinkles08 replied 1 year ago.
Hello and welcome to Justanswer!
There are a handful of things that could be preventing it from shifting into fourth. It could be an accelerator pedal position sensor, output speed sensor or vehicle speed signal issue, it could be the overdrive clutch solenoid, a leaking overdrive clutch piston, or a failure in the overdrive unit. If it had been slipping up until the point it wouldn't engage anymore then a leaking piston or failed overdrive clutch would be most likely. If there was abnormal noise up to or as it failed then a mechanical failure is likely.
The first step in diagnosing the problem is checking for fault codes. Have you checked for fault codes in both the ECM and PCM?