BMW 6 Series GT G32: Complete Guide to Reliability, Problems, and Maintenance
Quick Summary
The BMW 6 Series GT G32 (2017–2026) is a five-door Gran Turismo with a sweeping roofline that combines coupe comfort with wagon practicality. Under the hood are four engines: the B47D20 and B57D30 diesels, the B48B20 and B58B30 gasoline engines, all paired with the ZF 8HP automatic. The main weak spots are the air suspension, the adaptive shock absorbers, the EGR cooler on the diesels, and the panoramic roof drain channels. For maximum reliability, go for a B57D30 version without air suspension.
The Problem
You bought a premium BMW, and a few years into ownership the surprises start: the car sags to one side, a strange noise comes from under the hood, and the cabin smells like coolant. Sound familiar? The BMW 6 Series GT G32 is a complex modern car, and without knowing its weak spots, buying one can turn into an expensive repair. Here’s what fails most often—and how to avoid it.
Symptoms
- The car sags to one side after sitting overnight
- The air suspension compressor kicks in too often
- Worsening handling, oil streaks on the shock absorbers
- Coolant smell, spots under the car
- Water in the interior, especially under the carpets
- 26F500 fault on the instrument cluster
- Strange noise from under the hood on the diesel versions
Causes
Air suspension is one of the most common problems. Over time the air springs become porous and lose air. If you don’t catch the leak in time, the compressor runs itself into the ground and fails. Replacing the compressor is an expensive job.
Adaptive shock absorbers often start leaking oil past 75,000 miles. That hurts handling and calls for replacing the shock absorbers as complete assemblies.
The EGR cooler on the diesel versions was the subject of a BMW recall over fire risk. Before buying, always check that the recall work has been done.
Panoramic roof drain channels clog up, water gets into the interior and damages electronics. The power tailgate actuator—the electromechanical mechanism that opens the trunk automatically—also fails fairly often.
The Fix
B48 and B58 Engines
The main problem on the gasoline engines is a coolant leak through the oil filter housing. The plastic housing cracks over time and coolant seeps out. Both engines are affected. Replacing the housing is a manageable fix, but it takes care.
On the B58, the PCV membrane in the valve cover can rupture. That causes rough running, higher oil consumption, and a Check Engine light. The valve cover is replaced as a complete assembly.
The B58B30 itself, with its closed-deck engine block, is very sturdy. With timely maintenance it can go 124,000–186,000 miles without major failures.
B47 and B57 Diesel Engines
The B57D30 is the most efficient and comfortable diesel in the lineup and delivers a long cruising range. But on early diesels (built before 2018), check the timing chain—it can stretch, and that threatens serious damage.
The AdBlue/NOx system is temperamental: the 26F500 fault can appear even with healthy components. Sometimes a control unit reflash helps; in some cases, replacing the sensors.
Maintenance Schedule
| Parameter | Value |
|---|---|
| Oil change interval | 6,200–7,500 miles |
| Oil specification | BMW LL-01 or BMW LL-17FE+ |
| Cooling system check | every 43,000 miles |
| Air suspension inspection | every 62,000 miles |
| Panoramic roof drain cleaning | at least once a year |
Prevention / Used-Buying Checklist
- Check that the EGR cooler recall has been performed on diesels—it’s critical for safety
- Make sure there are no AdBlue/NOx faults (26F500)
- Inspect the rear air suspension for leaks: listen to the compressor, check the air springs for cracks
- Check the oil filter housing for cracks on the gasoline B48B20 and B58B30
- Check the timing chain on early diesels (pre-2018)—any odd noise from under the hood is a reason to walk away
- Make sure the power tailgate actuator works: open and close the trunk several times
Bottom Line
The BMW 6 Series GT G32 is a comfortable, roomy car with a trunk holding up to 1,800 liters, but its reliability depends directly on maintenance. The best pick is the 640d with the B57D30 diesel (235 kW) and no air suspension—that eliminates the most expensive repair. The gasoline 640i with the B58B30 is an excellent alternative for anyone who’d rather avoid diesel exhaust aftertreatment problems. The main rule: buy a car with a full service history and stick to the schedule—an oil change every 6,200–7,500 miles plus timely diagnostics of the weak spots.