Torque Converter Issues? Or Just Bad Fluid?

Ford told me my torque converter was bad and quoted $4,600 for the repair. But I added 2oz of Shudder Fixx, and the issue went away. Doesn’t this suggest the fluid might just be bad rather than the torque converter itself? Truck is a 2015 with 124k miles. Planning to change the transmission fluid and filter in a couple of days. What do you guys think—fluid issue or an actual torque converter problem?

I had a similar issue with my 2016 at 99k. Felt like driving over rumble strips in 5th and 6th gears. Transmission shop wanted to do a full rebuild, but I pushed for just a fluid and filter change. They weren’t happy and gave me all sorts of warnings about it ‘not even driving off the lift.’ Anyway, $350 later, the shudder was gone, and it’s been running great for 500 miles now. I say try the fluid change first—it’s way cheaper than jumping straight to a rebuild.

@Zoran
I hate when mechanics use scare tactics like that. ‘It might not drive off the lift’? That would’ve made me even more suspicious.

Zinnia said:
@Zoran
I hate when mechanics use scare tactics like that. ‘It might not drive off the lift’? That would’ve made me even more suspicious.

Yeah, I felt the same, but the shop had decent reviews, so I let them do the fluid change. I’m planning to inspect the pan myself when the weather warms up. Hopefully, they didn’t mess with anything.

Zinnia said:
@Zoran
I hate when mechanics use scare tactics like that. ‘It might not drive off the lift’? That would’ve made me even more suspicious.

Ford told me not to change the fluid because it could make things worse. Instead, they suggested changing it only after installing a new torque converter. So far, Shudder Fixx has helped, but I’ll post updates if it comes back after the fluid change.

Ford tech here. Torque converter shudder is common on 6-speed transmissions like the 6R80. While replacing the torque converter and doing a fluid exchange is the official fix, additives like Shudder Fixx can help temporarily. If you do a fluid change, make sure to use Motorcraft Mercon LV fluid. Don’t use aftermarket stuff—it doesn’t have the same friction modifiers.

@Hadley
Would you recommend a full flush or just a fluid change at this mileage?

Remy said:
@Hadley
Would you recommend a full flush or just a fluid change at this mileage?

If the transmission is otherwise fine, a flush would replace all the fluid. A fluid change only replaces about 75% of it. At 124k, I’d lean towards adding the Shudder Fixx and seeing how it goes, but flushing could help if the shudder persists.

That shudder usually means the clutch in the torque converter is wearing out. Additives like XL-3 friction modifier can help, but they’re temporary solutions. Long term, you may still need to replace the torque converter.

Had shuddering on my 2017 Expedition at around 70k miles. Changed the fluid and filter, and the shudder hasn’t returned in 20,000 miles. Worth a try before spending big money.

Beryl said:
Had shuddering on my 2017 Expedition at around 70k miles. Changed the fluid and filter, and the shudder hasn’t returned in 20,000 miles. Worth a try before spending big money.

Was your shudder as bad as the one in the last 15-20 seconds of this video? That’s what mine looked like after Ford’s diagnostic test.

@Remy
Mine felt just like driving over rumble strips, especially at highway speeds or uphill. Sounds similar to yours.

I had the same issue with my 2016. Mechanics all said it was the torque converter, but I did a fluid and filter change, and the rumble went away. That was 20k kilometers ago, and it’s still running fine.

@Robin
Sounds promising! I’m hoping to get another 20k miles out of mine before trading it in.

@Jo
Thanks for sharing! I’m aiming to get another 20k miles out of mine too. Fluid changes seem to be the way to go for now.

Had a slight shudder on my 2015 after towing a heavy RV. Transmission shop recommended a rebuild, but I went with a fluid and filter change plus Shudder Fixx. It’s been 4,000 miles, and the shudder hasn’t returned. If it does, I might consider a low-mileage used transmission.

My 2016 had the same rumble strip feeling. Dealer did a fluid and filter change, and it’s been smooth for 40,000 km. They said they’ve seen cases where the torque converter was replaced, but the issue persisted, so it’s always worth trying a fluid change first.

@Skylar
That’s refreshing to hear. My dealership told me not to bother with a fluid change and pushed for a new torque converter.

Changed my fluid and filter at 75k and again at 150k. Never had a shudder issue with my 2014 F-150 6-speed. Ford’s 150k-mile recommendation is way too long—change it earlier.

Shudder Fixx is a bandaid—it works for now, but you’ll eventually need a new torque converter or transmission.