Bought a new to me ( a first ) 2013 STX S/C 4X4 w/ 5.0. Been driving around for about 4 months. I have a wierd almost slip in third gear. Is the torque converter locking or unlocking while in gear? My 2010 with a 5.4 did not do that although it was tuned by Mike at 5 Star. When I was test driving trucks of all the things I looked at, I never once thought to notice. I did find this. Which may be what I am feeling. Not sure who posted it.

" I think it's the way the transmission is designed to work, nothing to really fix. If what you're talking about is what I think you're talking about. What I've noticed on mine (13) there is an rpm drop from first to second (naturally), then there's an rpm drop from 2nd to 3rd (expected) then another rpm drop (seems odd), another normal rpm drop from 3rd to 4th, etc. I assumed the double shift was the torque converter locking. Seems odd, but I've never driven another 6 spd so I assume that's how they designed it to work. I don't think I'd have noticed it if it wasn't for the numbered lights that show you what number gear you're in. Tuner might alter the rpm or road speed the converter locks, but I assume it'll still lock in that gear (3rd) at some point even with a tuner. But I'm not a transmission or tuning expert, so I could be wrong. "

Anyone else?

 

You found the answer. You probably won't feel it under heavy acceleration.

 

It's the converter locking up. At light load/low acceleration it locks to help improve economy.

 

It's the torque converter locking for economy and heat reduction.

 

Does it do that in 6th gear as well?

 

I'm in for the answer to this also. I feel the same thing on '13, EcoScrew, Max Tow in 6th sometimes. 7700 miles so I know it can't be slipping, must be some sort of lock/ unlock.


Ironically I don't recall feeling the 6th sensation on my previous truck 2011, 5.0L

 

The funky feel of my shifting besides the lack of throttle response is what made me decide to get a tuner. It felt like it was never going to finish shifting from 3rd to 4th. I loaded the custom economy tune and "tada" what a change. A totally different truck.

 

No. I thought it was at one time. I went to manual mode and dropped back to 5th & then 4th at about 50-55 MPH. Almost like a tire was out of balance. It is another case of a crappy paving job on the road I drive to work on every morning. BCMIF150 you are right. It does not do it under heavy acceleration.

 

Mine does this as well. I assume this is the 6R80 transmission?

 

Mine does that too. I hate it. It's like the TC can't make up it's mind what it wants to do in 3rd gear. Thankfully, my Omega tune has taken most of it out so I don't notice that much anymore. Now, the trans just feels crisp and temps. are lower.