Shudder until 30 MPH on moderate to heavy acceleration

[noahmb2005]

Hey all,

2010 SHO non PP, 135,000 miles

Just had my PTU replaced and after getting it back I have a harsh shudder and chirping noise when accelerating above half throttle, it gets worse when accelerating harder but goes away after about 30 MPH. The PTU was replaced by a ford dealer with a brand new unit. Any suggestions/ideas?

Thanks

 

[Zpak]

Torque converter

 

[Joshw0000]

Put a tube or 2 of Shudder Fixx in the transmission fluid. It'll instantly improve the issue. If it comes back, you need a new torque converter.

Sent from my Pixel 8 Pro using Tapatalk

 

[CharlieB]

Hey all,

2010 SHO non PP, 135,000 miles

Just had my PTU replaced and after getting it back I have a harsh shudder and chirping noise when accelerating above half throttle, it gets worse when accelerating harder but goes away after about 30 MPH. The PTU was replaced by a ford dealer with a brand new unit. Any suggestions/ideas?

Had exactly the same symptoms 2 months ago, 2013. Ford dealership said replace the transmission for 8K. Guys on the forum said it was probably the torque converter, and they were right. Changed the transmission fluid 4 times total. Problem was gone after the second change but because you can only drain half of the fluid, 6 qts v/s 12 qt. capacity, I changed it 2 more times to get as much of the old fluid out as possible. The friction coefficient of the fluid is the key and the older the fluid the less friction coefficient there is to spin up the turbine in the torque converter. Did a boat load of research after the problem was resolved and being an aircraft technician and traveling the country training people on jet engine propulsion it made all the sense in the world. Problem has not returned and the car is running great. Spent $200 on fluid and saved 8k on a new transmission.

 

[noahmb2005]

To update anyone else with this issue- took it back to the dealer and it was half a quart short on transmission fluid after the PTU job. Could’ve saved the time and checked myself but I’m at away at school right now and didn’t want to mess with it.
Thanks all

 

[CharlieB]

Hey all,

2010 SHO non PP, 135,000 miles

Just had my PTU replaced and after getting it back I have a harsh shudder and chirping noise when accelerating above half throttle, it gets worse when accelerating harder but goes away after about 30 MPH. The PTU was replaced by a ford dealer with a brand new unit. Any suggestions/ideas?

Thanks

I would strongly recommend changing the fluid in the transmission first before trying the shudder fix. If it is the torque converter, it can slip due to a breakdown of the friction coeeficient of the fluid. The Shudder Fix helps to restore that friction coeeficient but your still running with spent fluid. I tried new fluid on my 2013 SHO only. Changed it twice and it fixed the problem, but because you can only drain half of the bad fluid, I changed it 2 more times. Never ended up using the Shudder Fix and the car is running great.

Hey all,

2010 SHO non PP, 135,000 miles

Just had my PTU replaced and after getting it back I have a harsh shudder and chirping noise when accelerating above half throttle, it gets worse when accelerating harder but goes away after about 30 MPH. The PTU was replaced by a ford dealer with a brand new unit. Any suggestions/ideas?

Thanks

 

[kryptto]

I would strongly recommend changing the fluid in the transmission first before trying the shudder fix. If it is the torque converter, it can slip due to a breakdown of the friction coeeficient of the fluid. The Shudder Fix helps to restore that friction coeeficient but your still running with spent fluid. I tried new fluid on my 2013 SHO only. Changed it twice and it fixed the problem, but because you can only drain half of the bad fluid, I changed it 2 more times. Never ended up using the Shudder Fix and the car is running great.

back to proper and increased oil changes....