P0735 Code: Gear 5 Incorrect Ratio
Fifth gear slips or isn't fully applied; the TCM measures a ratio that doesn't fit 5th.
At a glance
Severity: Moderate
- Meaning
- Gear 5 Incorrect Ratio
- System
- Transmission · Powertrain
- Safe to drive?
- With caution
- Typical repair cost
- $100–$7,000
- DIY difficulty
- Hard
P0735 only appears on transmissions with at least five forward speeds. In a five-speed, 5th is usually the top overdrive gear used at highway speed; in six- to ten-speed units it's an overdrive or near-direct gear used at moderate cruising speeds. The TCM divides input speed by output speed while 5th is commanded and sets the code when the result is off target. In Honda's parallel-shaft five-speeds 5th has its own clutch, while GM six-speeds (6T40/6T45, 6L80) make 5th by combining the 3-5-reverse clutch with the 4-5-6 clutch. That shared hardware is the key to diagnosis: a problem that also affects 3rd and Reverse points to a different part than one that also affects 4th and 6th.
Can I keep driving? The car will usually still drive in the lower gears, so use manual mode to stay out of 5th and keep speeds moderate. If Reverse also becomes weak or disappears, have it looked at soon, because you may lose Reverse completely.
How to read P0735
- P Powertrain
- 0 Generic (SAE)
- 7 Transmission
- 35 Specific fault
Symptoms
- Won't upshift into 5th, or drops back to 4th after a few seconds
- Rpm flare on the 4-5 shift at 40–55 mph
- Slight rpm creep at steady highway cruise
- Weak or delayed Reverse on units where 5th shares the reverse clutch
- Reduced highway fuel economy
- Check engine light, sometimes with P0733 or a pressure control solenoid code
Possible causes
Ranked by how often each cause is behind this code (editorial estimate).
- Worn clutch pack that applies in 5th, often shared with 3rd/Reverse or 4th/6th
- Broken wave plate or return spring in a shared clutch pack
- Low or degraded fluid
- Pressure control solenoid for the 5th-gear clutch sticking
- Leaking sealing rings on the clutch drum feeding 5th
- Honda units: worn 5th clutch or faulty 5th clutch pressure switch
- Outdated software or adaptive values
Diagnosis step by step
Check Reverse and the other gears
Test Reverse from a stop and drive through every gear in manual mode. If 3rd, 5th and Reverse all misbehave on a GM six-speed, the 3-5-reverse clutch is the obvious suspect; if 4th and 6th also slip, look at the 4-5-6 clutch.
Tools: OBD-II scanner
Check the fluid
Check level and condition at the specified temperature. Many five-plus-speed units are sealed with a fill plug and need a scan tool to read fluid temperature during the check.
Tools: OBD-II scanner, Flashlight, Towels & shallow pan
Log the 4-5 shift and 5th-gear cruise
Record commanded gear, input speed, output speed and the clutch pressure control solenoid command. A ratio that drifts only at steady cruise suggests a leaking clutch circuit; a flare during the shift suggests slow apply.
Tools: OBD-II scanner
Check the clutch pressure control solenoids
On six-speed and newer units each clutch has its own pressure control solenoid. Compare commanded and actual current in scan data and measure resistance at the connector; a sticking solenoid can set P0735 and a solenoid performance code together.
Tools: Multimeter, OBD-II scanner
Try a software update and relearn
Some manufacturers have released TCM updates for shift quality and ratio monitoring. After fluid service or repairs, run the adaptive relearn procedure so the TCM relearns clutch fill times.
Tools: OBD-II scanner
Inspect the pan
Pieces of a broken wave plate or large amounts of friction material in the pan mean the transmission has to come out.
Tools: Towels & shallow pan, Torque wrench
Where the parts are
- 1Battery
- 2Alternator
- 3Engine computer (ECM)
- 4CAN bus
- 5Transmission
- 6Wheel speed sensor
- 7High-voltage battery
Repair options & costs
| Repair | DIY? | Estimated cost |
|---|---|---|
| Fluid service with adaptive relearn | No | $180–$450 |
| TCM software update | No | $100–$250 |
| Replace clutch pressure control solenoid or valve body | No | $450–$1,500 |
| Transmission overhaul with clutch pack and wave plate | No | $2,800–$5,500 |
| Remanufactured transmission, installed | No | $3,500–$7,000 |
Rough US estimates for parts and labor; shop rates vary by region. Not a quote.
Notes by brand
Chevrolet
The GM 6T40 and 6T45 six-speeds in the Cruze, Malibu, Equinox and Sonic are known for a breaking wave plate in the 3-5-reverse clutch. The classic sign is losing 3rd, 5th and Reverse together while 1st, 2nd, 4th and 6th still work.
Honda
Honda's five-speed automatics use a separate clutch and pressure switch for each gear. A 5th-gear ratio code with clean fluid can be a failing 5th clutch pressure switch; use only genuine Honda ATF when servicing.
Field data
| Ford | 5 | Escape, Expedition, F-150 SUPERCAB | |
|---|---|---|---|
| Chrysler | 2 | 300, TOWN & COUNTRY |
Source: NHTSA Complaints API (US government open data), analyzed by DTC mention.
Emissions / smog test impact
Will fail
Any stored P0735 keeps the check engine light on, which fails an OBD-based emissions inspection. Monitors must show ready after the repair.
Frequently asked questions
Why do 3rd, 5th and Reverse fail together?
On GM's six-speed automatics, the same clutch pack, called the 3-5-reverse clutch, is applied in all three. When it fails, those three gears go while the others keep working.
My transmission has eight speeds – is 5th still overdrive?
Not necessarily. On many eight- and ten-speed units, 5th or 6th is close to direct drive and the higher gears are overdrives. What matters for diagnosis is which clutches your transmission uses in 5th.
Is a software update worth trying?
It's cheap and quick, so it's worth asking the dealer if one exists. It won't fix a worn clutch, but it can correct shift timing or ratio monitoring that sets the code too easily.