Flushing the automatic gearbox in your motorhome: Fiat Ducato 9-speed and Mercedes Sprinter

According to Fiat Professional (2019), the Fiat Ducato is the most important base vehicle for motorhomes in Europe: three out of four motorhomes sold are built on a Ducato. Many motorhomes are also built on a Mercedes-Benz Sprinter. Both base vehicles have been supplied with different kinds of automatic gearbox. The difference matters, because it decides whether a flush makes sense. An automatic with a torque converter has a fluid coupling between the engine and the gearbox and changes gear with clutches that run in fluid. An automated manual gearbox is a manual gearbox with a clutch, in which an electronically controlled mechanism takes over changing gear and operating the clutch.

Sources: Fiat Professional (press releases of August 2007 and July 2019), Parkers (2019) on the Ducato 9Speed, Mercedes-Benz press information of 1 September 2021 on the Sprinter.

Fiat Professional introduced the 9-speed automatic with the model year 2020 Ducato, which was available from July 2019. According to Fiat, the gearbox works with a hydraulic torque converter instead of a friction clutch. The British magazine Parkers reports that it replaced the Comfort-Matic robotised gearbox and was offered with the 140, 160 and 180 hp engines. At Mercedes-Benz, the Sprinter received the 9G-Tronic in all variants with the 2021 model update, replacing the 7G-Tronic Plus. So a Sprinter from before that update can have a 7G-Tronic Plus, and an older Sprinter sometimes has a different type of gearbox. Call us with your registration number and we will look up which gearbox your motorhome has.

No. The Comfort-Matic is not an automatic with a torque converter, but a manual gearbox in which an actuator takes over changing gear. When it was launched in 2007, Fiat Professional described it as a traditional mechanical gearbox with six gears, in which an electronically controlled actuator replaces the gear lever. There is no clutch pedal. According to Fiat, the gearbox was available on the Ducato from January 2008. The clutch is that of a manual gearbox and does not run in automatic transmission fluid. A flush does not change that.

Complaints with a Comfort-Matic, such as jerky pulling away, a warning on the dashboard or a gearbox that will no longer engage a gear, can come from the clutch, the actuator or the adjustment. We can read out the gearbox and carry out a diagnosis. You hear in advance what is needed and what it costs. The same kind of gearbox is fitted to the Fiat 500 with Dualogic. Our article on the Fiat 500 Dualogic automatic explains more about how such a gearbox works. If the clutch is worn, our page on clutch replacement explains what is involved.

A motorhome is heavier, drives uphill more often and sometimes tows a trailer. This makes the fluid in the gearbox warmer, and warm fluid ages faster. Gearbox manufacturer ZF writes that it can make sense to change the fluid sooner with high temperatures and heavy loads, and when it is not known how the vehicle was used in the past.

For an automatic with a torque converter, our advice as a garage is to have the fluid changed or flushed every 60,000 to 80,000 kilometres, and for a motorhome closer to 60,000 than to 80,000 kilometres. That is our own cautious advice and not a Fiat or Mercedes-Benz requirement. So also check the service schedule for your base vehicle. For comparison: gearbox manufacturer ZF advises a fluid change after 150,000 km for its own automatics, and sooner with heavy loads or an unknown history.

If you only drive a few kilometres a year, the fluid still ages. A good moment for a check is before a long trip, so you set off with a healthy gearbox. Have the gearbox checked sooner if you notice one of these signs:

We follow the same procedure as for a car, because the Ducato’s 9-speed automatic and the Sprinter’s 7G- and 9G-Tronic are technically the same kind of gearbox as the car automatics we flush. We have five heavy-duty lifts, including lifts for motorhomes and commercial vehicles up to 3,500 kg. We do not treat motorhomes heavier than 3,500 kg.

1. Call with your registration number: we look up the base vehicle, the gearbox type and the prescribed fluid, and you hear in advance whether we can treat your motorhome.
2. Intake check and test drive: the mechanic pays attention to the moment of each gear change, slipping and jerks, with the gearbox both cold and warm.
3. Reading out: where possible, we read the transmission for stored faults.
4. Advice and quote: you hear whether a flush makes sense and what it costs. We only start once you have agreed.
5. Flush or fluid change: with the flushing machine and fluid to the prescribed specification. If the gearbox has a replaceable filter, we replace the filter and seal when that is part of the agreed work.
6. Check: we check the fluid level with the motorhome level and at the specified temperature, following the gearbox manufacturer’s procedure, and finish with a test drive. We dispose of the old fluid in line with the environmental rules for garages.

The treatment itself usually takes two to three hours. The motorhome is often ready the same day. You can read more about our method on our page about automatic gearbox flushing. Does your Sprinter have a 7G-Tronic Plus? Our article on Mercedes 7G-Tronic problems covers the common faults and the right fluid.

Yes. You can have everything done in one visit, for example before the season starts. The APK is the compulsory Dutch roadworthiness test, and we test motorhomes up to 3,500 kg. What the test involves is explained on our page about the APK for your motorhome.

Is the air conditioning in the cab no longer working properly? Our article on air conditioning in a motorhome or van (in Dutch) explains the difference between cab air conditioning and a roof unit. For other repairs to the base vehicle, see our page about motorhome repair. Call us with your registration number on +31 10 479 00 00 and we will plan the work together.

The 9-speed automatic arrived with the model year 2020 Ducato. An older Ducato with automatic operation usually has a Comfort-Matic. To be sure, check it using the registration number. Call us and we will look it up for you.

Yes. It is an automatic with a torque converter, like the conventional automatics in many cars. That is why we can maintain it with the same kind of procedure, after an intake check and a test drive.

No, that is not needed before every trip. A check before a long trip is sensible if the interval is coming up or if you notice shifting complaints. Plan it a few weeks ahead, so there is time for any extra work.

No. Our lifts for motorhomes and commercial vehicles go up to 3,500 kg. We do not treat heavier motorhomes.

That depends on the gearbox type, the amount of fluid and whether the gearbox has a filter. Call us with your registration number and you will receive a quote in advance. We only carry out extra work once you have agreed.

Yes. Fluid also ages with time, not only with kilometres. If you do not drive much, look not only at the mileage but also at how many years ago the fluid was last changed.

• Fiat Professional (Stellantis Media): Fiat Professional stellt den besten Ducato vor, den es je gab (4 July 2019, in German)
• Parkers: Fiat Ducato MY20: big van gets big update for 2019
• Fiat Professional (Stellantis Media): Fiat Professional presents the innovative Comfort-Matic robotised gearbox (20 August 2007)
• Mercedes-Benz Vans (press information via swisstruck.ch): Verkaufsstart im September: Mercedes-Benz Sprinter mit umfassend aktualisierter Antriebstechnik (1 September 2021, in German)
• ZF Aftermarket: ZF LifeguardFluid 8, product information (lifetime fluid and advice to change after 150,000 km)