NEED HELP Transmission jerks at 50-60 mph

[rene_320]

Hello GMTnation,

To give you some background history on my transmission. I bought the TB back in 08 with 64k on it and now it has 216k. I never did a flush or transmission filter change on it until now.

Back to my issue on my 05 TB last week it started to jerk when i would go 50-60 mph on the highway. So with (MAY03LT youtube video) i went ahead and change the transmission oil filter this past weekend. I didn't do a full flush on it because of the old stories about never changing the oil on a transmission with new one if you never did it because it might cause it to slip.
So I just put in what was take out of the pan which was about 4 qtrs.

When I did this the oil pans magnet had so much sludge which then i notices it was metal shavings or mixture of both. Well my TB is still doing the jerking at 50-60 mphs so my question to you guys is should i start to look into buying a rebuilt or used transmission?

Thank you in advance for any tips or opinions.

 

[littleblazer]

I'd say it could be on its way out. Question, if you put it in 3rd does this jerking stop and also could you describe a little more what it feels like?

 

[rene_320]

I'd say it could be on its way out. Question, if you put it in 3rd does this jerking stop and also could you describe a little more what it feels like?

Thanks for you input littleblazer, to answer your questions i havent tried shifting to 3rd and driving. I will try that once i get off of work.
Now to describe how it feels like, it feels like if a tug. I don't lose power it just feel like its struggling to shift into the next gear. The rpms start to jump and once i accelerate it stops.

 

[littleblazer]

Stupid question... you topped it off while running right?

The tugging could be the torque converter. I think using 3 prevents that from locking up. Or it still locks but in 3rd gear I forget...

 

[rene_320]

Stupid question... you topped it off while running right?

The tugging could be the torque converter. I think using 3 prevents that from locking up. Or it still locks but in 3rd gear I forget...

Yeah before turning it on i poured 3 qtrs and then turned it on added the 4th qtr.

Ill see if it still tugs on 3.

 

[C-ya]

It also sounds like it could be the TCC PWM issue. The valve body wears out from the piston constantly moving back and forth just a little bit as it responds to the PWM (pulse width modulated) signal for the TCC lockup. If the RPMs flutter just a few hundred, that seems like it might be a likely culprit. The TransGo SK4L60E kit has a fix for that. My tranny just got rebuilt (under aftermarket warranty) and I gave that kit to my mechanic to install. I only wanted the TCC PWM gone so we didn't use the entire kit. I also gave him a Beast sun shell and a Sonnax pinless accumulator for it as well. Shifts like a dream right now!

 

[gmcman]

Well, water under the bridge but transmissions need maintenance also.

You could have a filter thats restricted and starving of fluid. I would drop the pan, replace the filter and the fluid that came out of the pan.....4 to 5 qts.

Drive it and see what happens.

I agree the jerking could be the torque converter locking and unlocking but in stock form it's a modulated lock so may not be what's happening....hard to say.

 

[rene_320]

It also sounds like it could be the TCC PWM issue. The valve body wears out from the piston constantly moving back and forth just a little bit as it responds to the PWM (pulse width modulated) signal for the TCC lockup. If the RPMs flutter just a few hundred, that seems like it might be a likely culprit. The TransGo SK4L60E kit has a fix for that. My tranny just got rebuilt (under aftermarket warranty) and I gave that kit to my mechanic to install. I only wanted the TCC PWM gone so we didn't use the entire kit. I also gave him a Beast sun shell and a Sonnax pinless accumulator for it as well. Shifts like a dream right now!

Thank you for your input on this issue I'm having. It does sound like its the TCC PWM issue but then again I smell burning ATF now after driving it so much. I just found a transmission shop that is selling rebuilt 4L60E with 2 year warranty for $500 here in Houston so i might just drop my transmission and buy the rebuilt one.

Well, water under the bridge but transmissions need maintenance also.

You could have a filter thats restricted and starving of fluid. I would drop the pan, replace the filter and the fluid that came out of the pan.....4 to 5 qts.

Drive it and see what happens.

I agree the jerking could be the torque converter locking and unlocking but in stock form it's a modulated lock so may not be what's happening....hard to say.

Thanks gmcman for your input on my issue but it was doing it before i changed the transmission filter and before i threw away the old filter i checked to see if the fluid past through it and it actually did.

It does sound like the torque converter locking and unlocking like it shifts into 3rd but then it jerks/shudders. I'll take a video of what its doing and post it on here. Hopefully I can figure out how to post videos on here lol.
thanks again.

 

[C-ya]

I just found a transmission shop that is selling rebuilt 4L60E with 2 year warranty for $500 here in Houston so i might just drop my transmission and buy the rebuilt one.

If you can get a rebuilt tranny with that warranty for $500, I would jump on that with both feet! My tranny just got rebuilt and paid for by my aftermarket warranty. That and a new rack & pinion ran $3100. R&R of the tranny is about 10 hours on these vehicles, so labor is a large portion of that. Rebuilding was the option I took since the warranty co. wanted to do a junkyard unit. No thanks! It cost me an extra $250 of my own money but I would rather have a tranny that I can trust.

For the video, upload it to a site like Photobucket or even Youtube and post a link from there. That is the best and easiest way to post videos. I use Photobucket to post my pics as well.

 

[rene_320]

If you can get a rebuilt tranny with that warranty for $500, I would jump on that with both feet! My tranny just got rebuilt and paid for by my aftermarket warranty. That and a new rack & pinion ran $3100. R&R of the tranny is about 10 hours on these vehicles, so labor is a large portion of that. Rebuilding was the option I took since the warranty co. wanted to do a junkyard unit. No thanks! It cost me an extra $250 of my own money but I would rather have a tranny that I can trust.

For the video, upload it to a site like Photobucket or even Youtube and post a link from there. That is the best and easiest way to post videos. I use Photobucket to post my pics as well.

Well they are also offering to install for $350 which includes taking down old transmission and putting in the new one flushing the lines and adding new fluid. Only thing is the transmission that's rebuild doesn't come with torque converter which is another $120. So in all it would cost $970 which isn't bad I just don't want anything else to go bad with my TB.

Anywho here's a video of what's it doing.

 

[gmcman]

While this may not be related to your issue, if you are driving steady and the converter is locked...if you lift your foot off the accelerator pedal, even slightly, the converter will unlock then lock again if you regain a steady pace.

The metal in the pan is not a good sign, but I would make sure your TB harness is secure as well making sure your acceleration pedal is not acting up.

Not sure how to check the pedal, there is a failsafe between the pedal and throttle body which would result in a "Reduced Engine Power" mode but something to think about.

Based on the video, it could possibly, (slight possibility ) could be throttle related.