Terrible shake/shudder when coverter locks

patoka7.3 · Mar 17, 2016

I have a 2004 4 door short bed automatic truck that I just bought from Florida. It had a bad carrier bearing when I bought it so I thought that was the issue. The truck shifts and moves great until it locks the converter in od and the truck shakes and shimmys. As soon as the converter unlocks its fine again. Is this a symtom of the converter going bad or should I check other things first. Rear Driveline is tight all ujoints are New. Someone had told me to have the injectors checked.. It just have a slight weird idle but it doesn't haze or smoke or anything. There is no check engine line on and I have check for soft codes. Truck has 170k on it and it's solid. Just looking for some help!

sootie · Mar 17, 2016

check fuel pressure and icp.

could be injectors...

BS Hauler · Mar 18, 2016

I would say its injectors. When the converter locks up and rpm's drop with more load on motor you have a injector that is dropping out and the motor is trying to run on 7 cylinders.

DieselMater86 · Mar 19, 2016

I just went through the exact thing with my 03 its in the shop getting bullet proofed and built injectors. It finally got picked up by my monitor and I was having injector balance codes for two injectors. Just take it to a good shop and have it checked to know for sure. Good Luck and don't get frustrated with it take the right steps.

patoka7.3 · Mar 20, 2016

Yea it's extremely annoying. Any scanner with a live diagnostic scanner can do it correct?

Amarillo6.0 · Mar 23, 2016

Subscribed. My 06 is doing the exact same thing. When the TC is locked in OD the more throttle you give it the more violent it shakes. Doesn't do it often but when it does it worries the hell out of me. Mine also has a light bucking/lurching when sitting at a stop light on the brake with the trans in D. Again not always but when it feels like it. I'm praying it's not the TC...

JGman141 · Mar 23, 2016

Sounds like stiction to me, torque converters will just slip when they are on the way out

jake74 · Mar 26, 2016

My 04 with 255,000 miles on it does same thing. I added a bottle of archoil and that helped a lot. This truck has been been relegated to a weekend river beater so not going to spend any money fixing the ol gal.

shmoozer · Mar 26, 2016

My '04 does the same thing until up to full operating temp. Time for the 205's and a 369

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patoka7.3 · Mar 28, 2016

I do have a bad cylinder 1 injector so I'm hoping that's the issue

kersey1999 · Apr 1, 2016

My '04 is doing the same thing, going to auto parts place on way home to pick up a transmission additive that is supposed to eliminate shudder! Will update. Also my truck only does then when "cold" and between 45-60 mph....

mandkole · Apr 3, 2016

^^^ good luck with that

This is most likely a misfire issue under load as others have said. I saw it on a v10 4R100 motorhome and on a cummins with a brand new transmission/converter. The gasser had bad plugs and the diesel had injector issues.

JGman141 · Apr 6, 2016

kersey1999 said:
My '04 is doing the same thing, going to auto parts place on way home to pick up a transmission additive that is supposed to eliminate shudder! Will update. Also my truck only does then when "cold" and between 45-60 mph....

You more than likely have an injector issue, get a scan tool on it that can run a power balance

Atsah · Apr 6, 2016

kersey1999 said:
My '04 is doing the same thing, going to auto parts place on way home to pick up a transmission additive that is supposed to eliminate shudder! Will update. Also my truck only does then when "cold" and between 45-60 mph....

The last thing you need is a transmission additive..

The fact that it is doing it when it's cold is a sure sign of injector sticktion.. Most of the time when a 6.0 shutters in lock up, you have an injector issue..

Been there done that more than I like to admit..