Oil for a 722.9 automatic gearbox.

[JEEPWRANGLER2020]

I changed the oil in my automatic transmission 722.9; the vehicle has start-stop, and the VIN scanner indicates that the fluid is a Blue kind. The liquid that emerged, however, was a reddish (burnt) color, and the pan was filled with muck but no metal particles.

I emptied the converter tank but did not flush the cooler since I only had 10 litres of transmission fluid and the vehicle was scheduled for a MOT the next day. The fluid that emerged from the pan after draining at 45C was already becoming darker.

The vehicle genuinely seems much more agile, and the transmission appears to be functioning well, but there are a few things that bother me.

Do any of you know whether this gearbox can utilize red aftermarket transmission fluid, which the prior garage may have used? Or has the vehicle been using the incorrect fluid for a very long time?

Even though it's a pain in the rear when you don't have a vehicle lift and even before you include in the expense of the fluid and all the components, I may just wind up performing another fluid replacement.

[KARlosfuentes]

It seems that they used the incorrect gearbox fluid, which should be the same color and meet the same specifications as the fluid you used even if it was an alternative product. I'm not sure whether it's time for another modification, but if you must, you may always wait the normal five years and make the adjustment then.

[dontito]

If purchasing genuine MB ATF, the 7G transmission requires ATF to MB Specsheet 326.14 (Red).

If purchasing genuine MB ATF, the 7G+ transmission requires ATF to MB Specsheet 326.15 (Blue).

Fuchs Titan ATF is a popular aftermarket ATF that has the same color code as MB (326.14 Red, 326.25 Blue).

Sadly, I'm not aware of what color dye other producers could be utilizing.

MB326.15 should be noted as not being backwards compatible with earlier MB-ATF-Specifications.

[JEEPWRANGLER2020]

It seems that they used the incorrect gearbox fluid, which should be the same color and meet the same specifications as the fluid you used even if it was an alternative product. I'm not sure whether it's time for another modification, but if you must, you may always wait the normal five years and make the adjustment then.

Yes, I'm very convinced the incorrect fluid was used; I've noticed a significant difference in gear shifts, fuel efficiency, power delivery, and overall gearbox behavior. For example, it used to hesitate while accelerating after a tight right hand bend (like a little roundabout), but that is no longer the case.

[JEEPWRANGLER2020]

If purchasing genuine MB ATF, the 7G transmission requires ATF to MB Specsheet 326.14 (Red).

If purchasing genuine MB ATF, the 7G+ transmission requires ATF to MB Specsheet 326.15 (Blue).

Fuchs Titan ATF is a popular aftermarket ATF that has the same color code as MB (326.14 Red, 326.25 Blue).

Sadly, I'm not aware of what color dye other producers could be utilizing.

MB326.15 should be noted as not being backwards compatible with earlier MB-ATF-Specifications.

Thank you for the information, I believe I have located the error. Instead of oval shapes, my oil pan has dimples. You may be aware that it is conventional wisdom that a pan will accept red liquid if it has dimples.

A closer look reveals that my vehicle has an extra electric pump to help with the start-stop that is unique to the 7G Tronic plus. Additionally, the VIN number plainly shows the reduced friction gearbox code A89, and the vehicle certainly has start-stop.

In my situation, mixing the fluids shouldn't present too much of a challenge since my gearbox is built to handle low viscosity/reduced friction fluid, and both fluids are made up of 80–90% Petroleum C20–50 base with various additives.

But as soon as I can, I'll replace the fluid and cleanse the cooler.

The lesson of the tale. Don't base your decisions only on the presence or absence of dimples in the pan!

Many thanks, mystery is now resolved!

[matthewlightburn]

It seems that they used the incorrect gearbox fluid, which should be the same color and meet the same specifications as the fluid you used even if it was an alternative product. I'm not sure whether it's time for another modification, but if you must, you may always wait the normal five years and make the adjustment then.

If it is wrong fluid what possible reason could there be for running with it for 2 more years? What peace of mind does that bring?

[LostintheSea]

I concur. If it's the incorrect fluid, I'd replace it RIGHT AWAY.

[JEEPWRANGLER2020]

I concur. If it's the incorrect fluid, I'd replace it RIGHT AWAY.

The MSDS indicates that this situation shouldn't provide a significant challenge since the same base is used in both formulations, but the new ATF contains different friction modifiers and extra solvents.

It would be far more urgent to put the proper fluid in if it were done the other way around, i.e. pouring blue ATF to the old gearbox.

However, I have already placed an order for a new filter kit, and I'll pick up the replacement fluid on Tuesday.

As an aside, I discovered that the original MB fluid was around £40 per 5Lt, which is comparable to or even less expensive than other brands.

[James_Cam00]

Shell ATF-134 is the most cost-effective option, but you should be good with any fuel that satisfies the 236.12 criteria.

[Alvinthebeast]

That should be for the 5g, right?