[Cciman]

This is starting to get more frequent and noticeable. 62TE 2011 TC 3.6

I get a shudder when on throttle at 1500 and 3000 rpm. Disappears when I let off throttle and immediately reapply. I am guessing that it is the transmission - not downshifting. Recent fluid and filter change last summer.

Any had similar symptoms, what was causing it?

 

[Sienile]

Maybe CVs binding. Check motor mounts and front suspension.

 

[Jeepman]

You know, the Wynn's transmission flush video, using the transmission's oil pump, includes an application of Wynn's shutter fix "for added protection to the transmission fluid", as a finishing touch. So they say.

Perhaps try a 2oz application of Lubegard to see if your problem is fluid or torque converter related.

 

[Cciman]

That LUBGUARD was added at the time of fluid change, last summer, and I used the cooler lines to "flush" much of the old fluid out. So I think the fluid is pretty good. I'll double check level.

It still feels as if it is not downshifting correctly at those RPM's. I don't think motor mounts or suspension is it. CV binding should occur at random rpms.

What are the symptoms of a bad solenoid?

 

[Sienile]

Just going off the chemicals listed in the MSDS, all Lubeguard will do is bond to the fluid making it thicker. That can impede flow in small channels, like solenoid passages.

Bad solenoids can cause missing or sloppy shifts, so that is a possibility. If it's bad enough you'll get a ratio code.

 

[Jeepman]

Just going off the chemicals listed in the MSDS, all Lubeguard will do is bond to the fluid making it thicker. That can impede flow in small channels, like solenoid passages.

Friction modifiers in 2 oz of carrier fluid thickening the transmission fluid?

Instant Shudder Fixx - Lubegard

www.lubegard.com

.

 

[Sienile]

Amine alkyl phosphate, is an alkaline phosphate salt that is missing a hydrogen atom and eager to bond to one. Where's it going to find that hydrogen atom? The hydrocarbons in the ATF. A bonded molecule is thicker, so greater viscosity.

 

[Jeepman]

Amine alkyl phosphate, is an alkaline phosphate salt that is missing a hydrogen atom and eager to bond to one. Where's it going to find that hydrogen atom? The hydrocarbons in the ATF. A bonded molecule is thicker, so greater viscosity.

What change in viscosity, if any, would 2 oz of Lubegard Shudder Fix make to 9 quarts of ATF+4?
A good project for Project Farm.

 

[Long_Voyager94]

Just going off the chemicals listed in the MSDS, all Lubeguard will do is bond to the fluid making it thicker. That can impede flow in small channels, like solenoid passages.

Bad solenoids can cause missing or sloppy shifts, so that is a possibility. If it's bad enough you'll get a ratio code.

Again and again and again this comes up and NO ONE listens until they end up frying their transmission.

 

[Cciman]

Recap: Shudder at 1300 and 3000 rpm under load.

I'm told by tranny shop that the this is symptom of a torque converter going bad. $1200 fix. Ouch.
Currently at 159K miles. 1st fluid change at 149K miles, last summer.
No computer codes

Is this possible for other causes like selenoid, valve body?
Anyway to narrow it down?

 

[Jeepman]

The suspensions aren't that great at dampening out worn road surface undulations. New front struts may make a difference, a new right front strut on mine made a big difference. Old one was leaking and on its last legs. Is this occurring on all road surfaces? A Mechanic, I know, with a newish 2020 DGC GT, blames the shake on hard tires.

Torque converter shudders tend to be at low speeds like 45 mph and can be temperature related.

Torque Converter Shudder Problems

A torque converter is the fluid coupling between an engine and transmission that allows the engine to idle at low speed without engaging the transmission.

itstillruns.com

 

[Sienile]

If when you did you fluid change you only did a single drain and fill, you may have worn out fluid that's not performing as well as it should. The fact that you did the first fluid change at 149k in itself could have caused internal damage that is just now getting to a point that it causes issues. Even by the manual's lax recommendation, you were way overdue.

I know you were quick to dismiss my original suggestions, but those are among the most common reasons for shuddering on these. You might surprise yourself and find a worn control arm bushing putting you at a misalignment is causing all this.

But if it really is T/C shudder, the solenoid could potentially be the issue as could simple fluid condition.