Failing Torque Converter

Hi everyone,

Has anyone had to deal with a failing torque converter in their 3rd gen yet? I have a friend who's truck has a hesitation (almost a stumble) when at steady throttle and in almost all gears. It begins at around 20mph, resembling a torque converter going in and out of lock up. The truck has 79k miles on it and has been well maintained.

The dealership has performed both TSB's 005818 and 006218. They told him that this will be the 10th T/C in a year they have replaced.

Any other experience would be appreciated.

 

Your friend needs to monitor the proper PIDS and actually see what's going on.

BTW there's plenty of reports of stuttering/shuddering/hesitations under load on TW. FWIW, some manual trans trucks do it to (like both 3rd gens I've owned).. so it may not be the transmission at all. Heck, it probably isn't a hardware problem, but rather factory tuning (ECM calibration).

 

What PIDS would you recommend?

 

Low on ATF? I would hope the dealer would check that, but maybe not

 

I've used Techstream and OBD Fusion to monitor PIDS on my truck.. but since it's a M/T, well I don't know the exact answer. There is one for TC lockup AFAIK.

A/T guys will chime in.

 

Thanks, T/C lock does not change when the stumble is present.

 

Does the truck have larger tires and stock gearing?

 

If the TC is locked and there's a stumble, it ain't the TC.

 

Factory gearing and tire size.

 

Did the owner buy this truck new, or did he pick it up recently with that mileage on it?

In other words, are these symptoms new.. or is the truck new to your friend?

 

Purchased new, symptoms started in the last few weeks.

 

Interesting, both of your trucks did that?
My 18 has never done that, even on stock tune. I have always used 91 E0, maybe thats why?

 

I'm on the newest AT ecm factory calibration and have felt the same thing every once in a while. If you have felt it in an MT, I wonder if it's the switch between port and direct injection during light load situations. There's a cleaning cycle when stopped but the 2GR-FKS uses both mpi and gdi depending on load when traveling and switches between Atkinson and Otto cycles. Sounds like a blip during one or both of the switches...

 

Ah ok..

 

Yessir.
Tuned or stock, both trucks.

That's why it's difficult to convince some ppl that the stutter issue exists, because not all trucks do it.

91 E0 here too, still does it.

 

Mine was replaced a year ago on my '16 sport AT 4x4 (stock everything, California 87 gas) with ~38k miles
Was most noticable around 20mph turning to a slight incline. Haven't had any trouble since replacement.

 

Have they done a drain and fill with new fluid? I thought mine was doing funny stuff (slipping/hesitant) so I did a drain and fill twice with 6 quarts and my issues went away. I don't know if it will fix your friends transmission but worth a try. Search 3rd gen trans issues many have replaced fluid and fixed their issues.

 

At 20mph you're nowhere near full lock...probably flex lockup/torque converter clutch.
You need to monitor solenoid SLU or SLT...I forget which.
Even then, it will only indicate a go/no-go condition...performance of hardware can degrade and never set off any bells or whistles.

 

Tell your friend to run a couple of tanks of premium and see what happens. My truck along with a lot of others has a low throttle/low load miss. 93 makes it right. Cheap and easy to test.

58K on my AT to back it up.

None of this is for the tranny obviously, but to eliminate another source of shudder that some trucks have.

 

Which in turn would confirm fluid level, if done properly