Transmission shudder

[Phil13SHO]

Glad I didn't tune my 13 SHO PP yet. The car has 103k miles and just realized I still have 300 miles left on my base care warranty so hoping it can be sorted out. I have owned the car since 79k miles and I have never tuned the car.

Car seems to shift fine during normal operations but when I'm doing about 40+ and I floor it to where the trans kicks down, it downshifts no problem but right after it does, it does some kind of weird shudder/slip and then continues on accelerating. I tried at 40mph, freeway speeds, tc off/on and still does it.

Going to take it to dealer this week to see if they can figure out.

 

[ridered74]

Have you ever changed the spark plugs?

 

[krewat]

Check the fluid level. Having read on here that putting an extra bit of fluid helps, and it sounds exactly like what you're experiencing...

 

[Zpak]

Get it in quick. I’m taking mine tomorrow for the same thing. The torque converter is bad. When you accelerate after a downshift or kick down the trans would slip and I can watch the RPM’s bounce. It finally got mine to do it with the ford tech in the car. Just slipped it in with one month and 700 miles left of powertrain warranty. They thought plugs at first, tested ok, then came back and told me it was the torque converter.

 

[Zpak]

I meant to start a thread about this to warn people but I’m new here and couldn’t figure out how to do it. Maybe because I’m using a phone instead of a computer. But yeah, I haven’t asked yet how they determined the torque converter was the cause but if you’re experiencing what I described that would be a good place to look, unfortunately. It’s been going on for some time now but has just recently gotten bad enough to happen all the time. The one sure way I fount to reproduce the condition is travel 50-60mph, coast to under 40 and wait for the downshift then get back on the gas with about half throttle. I get a, woo wo sound, and the RPM’s will bounce for a few seconds until it finally connects.

 

[Phil13SHO]

I have 300 miles left on warranty and I am dropping car off Wednesday morning. Not going to drive it until then. It does it every time the car kicks down 2 gears at full throttle. . I am guessing the usual will happen at dealer. Oh, we didn't notice any issue - couldn't replicate the problem. Diagnostic fee $150.

 

[Johnbigdog]

I have 300 miles left on warranty and I am dropping car off Wednesday morning. Not going to drive it until then. It does it every time the car kicks down 2 gears at full throttle. . I am guessing the usual will happen at dealer. Oh, we didn't notice any issue - couldn't replicate the problem. Diagnostic fee $150.

If that's the case, go on a test drive with the service manager, shop Forman or a writer before you pick it up.

 

[Phil13SHO]

Dealer replacing ptu under warranty. They said 2 plugs look like they need replacing, something about arc, and 2 coil wires cracked or something like that.

 

[Zpak]

Dealer replacing ptu under warranty. They said 2 plugs look like they need replacing, something about arc, and 2 coil wires cracked or something like that.

What did they say was wrong with the PTU.

 

[Phil13SHO]

They said the vent tube was cracked but i told them it smelled.