If you own a 2022 Chevrolet Suburban or Tahoe, you may notice your transmission leaks fluid onto the garage floor. Rejoice in the knowledge that yours isn’t the only one with this problem. It is common enough that GM has issued a GM TechLink report about it. There are also recommendations for what to do to fix leaking 10-speed transmissions.

The GM 10L80 10-speed automatic has leak issues. They occur around any of the rear case plugs, of which there are three. Two large case plugs are on the driver’s side of the transmission case above the pan, with a smaller third plug on top of the case. Those side plugs are where the leaks are coming from.

How are the leaky Chevrolet transmissions fixed?

According to the TechLink information, the larger plugs have “CAR” embossed into one and “TRK” on the other. These case plugs are for factory settings and are not for servicing the transmission. The service bulletin suggests to GM service techs what to do if one or both caps are leaking.

It advises determining which plug is leaking and removing it. But that entails first removing the transmission cross-member support and mount. This allows for better access to the plugs.

The leaking plug or plugs are removed. Using a brake clean-type solvent is recommended to remove all of the fluid residue in the plug hole, and then a new plug is applied with a thread sealant.

Are the Ford and Chevrolet 10-speed transmissions the same?

These triple clutch assembly transmissions were first put into various 2018 GM vehicles including its trucks, SUVs, and Chevrolet Camaro SS starting in 2019. The transmission development was a joint effort with both Ford and GM. However, the cases for each are different as are a few internal components, but they’re essentially the same. 

Assembly takes place at their respective factories. That means for Ford its Livonia Transmission plant and later its Sharonville Transmission plant. GM’s 10-speed automatic is built at its Romulus Powertrain plant in Michigan. 

What other models have this transmission?

Here is a list of which models use the GM 10L80 or GM 10L90 variant:

10L80 MF6

• 2018– Chevrolet Suburban
• 2018– Cadillac Escalade
• 2018– Chevrolet Tahoe
• 2018– GMC Yukon Denali
• 2019– Chevrolet Camaro SS
• 2019– Chevrolet Silverado (Except V6 models, which use the 6L80}
• 2019– GMC Sierra (Except V6 models, which use the 6L80)

10L90 MGL

• 2017– Chevrolet Camaro ZL1
• 2019– Cadillac CT6
• 2020– Cadillac CT5
• 2020– Cadillac CT4

If your GM 10-speed has leaks you should contact your local GM dealer to have it inspected. The warranty will cover any of these problems.