Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
Your car's transmission is slipping, meaning it's having trouble staying in gear or shifting gears properly.
The transmission control module (TCM) has detected that one of the friction elements in the transmission, specifically Element D, is slipping more than it should.
The P079D code indicates that the transmission control module (TCM) has detected excessive slip in one of the friction elements, referred to as Element D. This slip can occur due to worn clutches, low hydraulic pressure, or other mechanical failures within the transmission.
• Transmission slipping
• Harsh or delayed shifting
• Check Engine Light illuminated
• Worn or damaged transmission clutches
• Low transmission fluid level
• Faulty transmission solenoid
Transmission: A system in a vehicle that transmits power from the engine to the wheels.
Friction Element: Components within a transmission that use friction to transfer power and control gear shifts.
• Check transmission fluid level and condition
• Inspect for transmission leaks
• Perform a transmission pressure test
• Replace or repair worn clutches
• Refill or replace transmission fluid
• Replace faulty transmission solenoid
• OBD-II scanner
• Transmission fluid pressure gauge
• Basic hand tools
$500 - $2000
Difficult
• Ford F-150
• Chevrolet Silverado
• Toyota Camry
• Regular transmission fluid changes
• Avoid aggressive driving
• Regular transmission inspections
Transmission Performance
• Avoid driving aggressively until the issue is resolved
• Consult a professional mechanic for a thorough diagnosis
Transmission repairs may be covered under powertrain warranty if the vehicle is still within the warranty period.
The P079D code has been increasingly reported in vehicles with higher mileage, often due to wear and tear on transmission components.
High – Driving with a slipping transmission can lead to further damage and potential safety issues.
Driving with a slipping transmission can be dangerous and may result in loss of vehicle control.
• Vehicle at operating temperature
• Transmission in drive mode
The transmission friction elements are located within the transmission assembly, which is typically mounted between the engine and the drive shaft.
Q: Can I drive with a P079D code?
A: It's not recommended to drive with this code as it can lead to further transmission damage.
Q: How can I prevent transmission slip?
A: Regular maintenance, including fluid changes and avoiding aggressive driving, can help prevent transmission slip.
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