722.8 Mercedes Transmission — information about rebuild
Transmission of the 8th series Mercedes 722.8 (released in 2005) is often found on the Mercedes A170 series. This variator was installed on other cars of the A series in the 160-m body with engines from 1.5 to 2.0 liters and on Tourers of the B series.
Its design is based on the standard patent of a variator with a «pushing» belt produced by Bosch-Fondorn and the most expensive consumable — the belt itself. This is an analog and competitor of the legendary Japanese variator JF011E.
The pump is of the Mercedes series and rotary type, which creates huge pressure. It is quite reliable compared to the Japanese and goes to the end of the life of the variator. The hardware of the CVT 722.8 from Mercedes is traditionally reliable.
The transmission Mercedes 722.8 was produced from 2004 to 2012 and was only available on A-Class and B-Class models with engines up to 2.0 liters and 300 Nm of torque.
722.8 Fluid and filter change
The oil filter of ATF 28-CVT type is used. Standard fluid Titan CVT is produced for Mercedes FUCHS.
Fluid Type: ATF 28-CVT
Capacity: 4.5-5.5 liters
Video how to change fluid:
Fluid in the variator 722.8 should be changed as often as possible along with the felt filter, carefully examining the magnets for metal chips. If the crumb on the magnets appeared — you should examine the hydro block and the board, which also accumulates magnetic crumbs and then do cleaning as often as the engine oil maintenance. This will extend the life of the board.
Besides oil overheating, the main problem is the failure of the control unit (board) of the gearbox 722.8. The transmission becomes in emergency mode, the inscription «Transmission Visit Workshop» lights up on the instrument panel. In this case, computer diagnostics shows one or more errors.
Mercedes 722.8 transmission problems and breakdowns
In the first repairs, 722.8 transmission comes due to the traditional fault of sub-suppliers — overheating and failure of the control board.
Overhauls with bulkhead age machines usually require a set of consumables (gaskets and seals) and a set of frictions. Masters often change both packages of frictions at once, since the variator 722.8 is removed along with the engine, and the frictions ruined by half already include the clutch with shocks. Therefore, when overhauling, it is considered unwise to save on reverse clutches.
Riding with worn rings and seals leads to oil starvation and premature combustion of «eternal» frictions. Therefore, you should always order a repair kit of gaskets and seals to rebuild Mercedes 722.8.
ECU Problems video
The oil pump of the rotary type, which creates a huge pressure, is mounted on top of the hydro block. The variator is very reliable on the mechanical part, but it can break because of improper operation. If the oil is not changed for a long time, it becomes very dirty, and the transmission overheats. Few people know that if you run over 100,000 km and change the oil in a good way, you need to change the heat exchanger (radiator of the variator), because it is clogged with impurities in dirty oil.
Electric problems
The construction is much more reliable than electrics. Electrics is a weak spot of Mercedes 722.8 transmissions. The payment was made by a partner company of Mercedes, and after the warranty period, the problems of dirty oil (metal dust) and overheating begin. Steel dust, which is magnetized on the sensors along with the overheating of the oil, puts them out of action. Sensor replacement – board repair Mercedes 722.8 is the most popular type of maintenance.
722.8 Transmission diagram scheme parts
Valve body and solenoids manual
Valve body manual 722.8 CVT
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