P0829 moderate

5-6 Shift

The P0829 code means the vehicle's onboard diagnostic system has detected: 5-6 Shift. This is a moderate severity code.

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Keep driving?: Short distances only
DIY difficulty: hard
Estimated cost: $200 - $2,500 (parts and labor)

Check Your Fluid First

ANCEL AD310 OBD-II Scanner

Read and clear transmission codes. Many trans codes are caused by low or burnt fluid -- check level and color before assuming the worst.

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Read Transmission Codes

LAUNCH CRP123X (Reads All Systems)

Basic scanners only read engine codes. This reads transmission, ABS, and airbag too.

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Common Symptoms

Check Engine Light illuminated
Harsh or delayed 5th to 6th gear shift
Transmission slips during 5-6 upshift
Vehicle may stay in 5th gear and not upshift to 6th

Probable Causes (Ranked by Likelihood)

Worn 5-6 shift clutch pack or band Very High
Faulty 5-6 shift solenoid High
Low or degraded transmission fluid Moderate
TCM calibration issue or internal valve body wear Low

Step-by-Step Diagnostic Procedure

Check transmission fluid level and condition
Monitor 5-6 shift timing and quality with a scan tool
Test 5-6 shift solenoid resistance and operation
Perform a transmission line pressure test during 5-6 shift

Frequently Asked Questions

What does a 5-6 shift code mean?

P0829 indicates the TCM detected an issue with the shift from 5th to 6th gear. This could be slippage, harsh engagement, or failure to complete the shift.

Is this a sign of internal transmission damage?

It can be. If the 5-6 clutch pack is worn, internal transmission work or a rebuild may be needed. However, a faulty solenoid or low fluid are less expensive fixes.

Will changing transmission fluid help?

If the fluid is low or severely degraded, a fluid change may improve shifting. However, if the clutch pack is worn, fluid alone will not fix the problem.