I have a 2015 F150 5.0 with the 6R80. Since I bought the truck at 111,000 miles, I have noticed a “clunk” around 30mph while decelerating. It seems to happen most when the trans is cold or lukewarm. I have done 3 drain and fills with Amsoil ATL. It is less pronounced, but still happens occasionally. Is this normal operation or am I seeing early signs of torque converter failure? Appreciate the help
6R80 “Clunk” Upon Torque Converter Disengaging
- Thread starter brandon9715
- Start date
Have you heard about the recall on the transmissions?
From what I understand the recall does not apply to 2015, but I could be wrong. I have not received any recall notice.
Check the slip yolk on the driveshaft.
Yep. Was going to mention this. For some reason Ford has never figured out 2 piece driveshafts. My buddies 2003 F150 clunks and so does my 2020 Ranger. (Or rather it did, it is properly lubed now)
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It’s not right when I stop accelerating, it’s always around the 30 mph mark and it almost feels like I hit something. It’s like something grabs suddenly.
Both the two piece and one peice driveahfts clunk like this. You need to properly lube the splines with the ford grease. Their vendor is not disclosed, Id love to find what kind of grease this is.
If it was driveshaft wouldn’t it happen all the time and not just while tranny is cold at low speed?
Generally yes. My 09 would clunk when it rocked back once you stopped and the same when you started accelerating. Lubed that shaft every couple of years to keep it smooth.
It doesn’t do that really. It’s more of a “grab” right as the torque converter engages while slowing down and tranny is cold.