--- title: "Silverado 2500 transmission cooler line separates at the crimp" kind: "owner-report" recall: false brand: "chevrolet" model: "silverado-2500" year: 2021 slug: "chevrolet-silverado-2500-trans-cooler-line" url: "https://www.rigfixhq.com/issues/chevrolet/silverado-2500/2021/chevrolet-silverado-2500-trans-cooler-line" markdownUrl: "https://www.rigfixhq.com/issues/chevrolet/silverado-2500/2021/chevrolet-silverado-2500-trans-cooler-line.md" --- # Silverado 2500 transmission cooler line separates at the crimp Owner reports are not official NHTSA recalls. Each report cites a public complaint, bulletin, forum thread, or manufacturer page. It is not a failure rate, a diagnosis, or a repair procedure. **Owner report** · Transmission · 2021 Chevrolet Silverado 2500 ## Symptoms NHTSA complaints on the 2020 and 2021 Chevrolet Silverado 2500 describe a transmission cooler line that separates at the crimp where the rubber hose meets the metal line. Complaint ODI 11765810, on a 2020 Silverado 2500, says that on the highway the cooling line separated at that crimp, fluid covered the vehicle including the windshield and the trailer, and the truck stopped pulling. The owner wrote that the transmission failed, that the repair was about $10,000, that GM covered some of it, and that the owner was left with a $5,000 bill on a truck under 100,000 miles. Those figures are the owner's. The owner wrote that there was no warning before the failure. Complaint ODI 11569212 says that at about 55 mph smoke came from the rear, the truck lost power, and transmission fluid was leaking from the rear. A dealer said the transmission cooling line had failed and needed replacement. The truck was not repaired. The owner wrote that extended coverage was issued but the VIN was not included. The mileage is 67,000. Complaint ODI 11566370 says that at 55 mph the tachometer was erratic, the truck lost power, and fluid pooled underneath. A dealer said the transmission oil cooler line failed at the crimp, and that an electric parking brake failure had worn the pads and rotors. That brake finding is in the same filing and is not the cooler line. The first dealer did not repair the truck. A second dealer confirmed the line failure, said the transmission was damaged, and the truck was repaired. The owner related the failure to customer satisfaction program N212326940 and wrote that the VIN was not included. The mileage is 67,000. This page does not have that program, so it does not say what the program covers. Complaint ODI 11561441 says the cooler line separated at the crimp, fluid sprayed on the hot exhaust, and the truck lost propulsion while merging onto the highway. Complaint ODI 11566508, on a 2021 Silverado 2500, says the line from the radiator to the cooler came apart at the crimp, fluid sprayed, and the truck was stranded. Complaint ODI 11563860 says that at 40 mph the crimp connection came apart, the fluid ran out, and the truck was stranded in the road. A 2020 GMC Sierra 2500 complaint, ODI 11646185, says that at 30 mph the engine revved and the truck lost power in the road, fluid leaked while it was towed, and Ryan's Repair diagnosed a fractured transmission cooler line. The truck was not repaired. The mileage is about 112,000. The owner wrote that the manufacturer gave no help because the VIN was not in the TSB. That filing does not name a bulletin number, and it is a Sierra, not this model. This page does not have a 2020 or 2021 cooler-line bulletin. These filings do not show a separated line on every 2020 or 2021 Silverado 2500. ## Likely causes The complaints say the rubber-to-metal crimp on the transmission cooler line separated, and that fluid left the transmission. One dealer also named an electric parking brake failure in the same visit. The filings do not include a lab report on the crimp. They do not show one failed line on every truck. A Sierra owner wrote that a VIN was not in a TSB. This page does not have that document. ## Common fixes If the truck loses pull and you see transmission fluid on the road, the bumper, or the trailer, stop. That is what these complaints describe. Do not keep driving to finish a tow after the line has separated. Fluid on a hot exhaust is what one 2020 complaint describes. The complaints describe a dealer replacing the cooler line, and in two accounts the transmission was also damaged. Ask the dealer to look at the crimp and to say whether the transmission itself was hurt before you approve a rebuild. This page does not have a part number or a procedure. ## DIY difficulty Seeing fluid on the ground is what these owners describe. Replacing the line, in these complaints, was a dealer or a repair shop. There is no published procedure here. ## Parts needed No GM part number is named. The complaints describe the transmission cooler line, the rubber hose, the metal line, and the crimp. Two complaints also describe a damaged transmission. ## Warranty notes This is not a recall. This page does not have a 2020 or 2021 cooler-line bulletin. One owner named customer satisfaction program N212326940 and wrote that the VIN was not included. Another wrote that extended coverage existed and that the VIN was not on it. The highway complaint says GM covered some of a transmission repair and left the owner with $5,000. Those outcomes are that owner's. A complaint is not a coverage decision, a failure rate, or a diagnosis for another Silverado 2500. The years on this page are 2020 and 2021, which are the years these cooler-line complaints name. The 2020 Sierra 2500 complaint is a different model and is not given a year on a Sierra page here. The 2024 valve-body report on this model is a different page. Recall 24V-797 is a different campaign, for certain 2020 through 2022 diesel transmission valves. ## Sources - [NHTSA complaints for 2020 Chevrolet Silverado 2500 (ODI 11765810, 11569212, 11566370, and 11561441)](https://api.nhtsa.gov/complaints/complaintsByVehicle?make=CHEVROLET&model=SILVERADO+2500&modelYear=2020) - [NHTSA complaints for 2021 Chevrolet Silverado 2500 (ODI 11566508 and 11563860)](https://api.nhtsa.gov/complaints/complaintsByVehicle?make=CHEVROLET&model=SILVERADO+2500&modelYear=2021) - [NHTSA complaints for 2020 GMC Sierra 2500 (ODI 11646185, a cooler-line report on a different model)](https://api.nhtsa.gov/complaints/complaintsByVehicle?make=GMC&model=SIERRA+2500&modelYear=2020) Year page: [2021 Chevrolet Silverado 2500](https://www.rigfixhq.com/issues/chevrolet/silverado-2500/2021) HTML page: https://www.rigfixhq.com/issues/chevrolet/silverado-2500/2021/chevrolet-silverado-2500-trans-cooler-line