Hard Downshift To Pass

[jeffbazell1]

2018 Premium, eAssist, 83k miles. When I'm flooring it to downshift into passing gear, it's a really hard shift. According to CARFAX maintenance history (if you can believe them), the previous owner did a tranny fluid flush at 40k miles. Anyone experience a hard downshift when flooring it to pass? Or is it 'the nature of the beast' on these 6T40 trannys?

 

[iownabuick]

I got a 3.6 model and have not had that issue. i would do a fluid change though every 40k miles. see if that helps. it should also assist in keeping the tranny good for longer. i did mine at ~40k and noticed a huge difference in smoothness of shifts. didnt even realize it was not shifting completely right until after the change where youll not feel them in most circumstances, basically made it feel like new again. dont believe *lifetime fluid* claims, its not worth it.

 

[richardnewton]

We have the 6T40 in a 2013 LaCrosse 2.4 eAssist.

It started to get a bit clunky at about 40k miles. We had the dealer service the fluid and is much smoother now.

There always is some risk with fluid services and these are not the most "robust" transmissions so be gentle.

 

[jeffbazell1]

I got a 3.6 model and have not had that issue. i would do a fluid change though every 40k miles. see if that helps. it should also assist in keeping the tranny good for longer. i did mine at ~40k and noticed a huge difference in smoothness of shifts. didnt even realize it was not shifting completely right until after the change where youll not feel them in most circumstances, basically made it feel like new again. dont believe *lifetime fluid* claims, its not worth it.

I changed (drain/fill) the fluid today (83,716 miles). Old fluid was almost black. Drained just under 5 qts, had to put in about 5.5 qts., Checked level using the level check port, filled till it started dripping out, tightened, warmed up, ran thru gears, test drove. I don't know if it's my imagination but it really is shifting smoother all the up to 6th. It still clunks into passing gear but not as much. It needed the change for sure. CARFAX said it was last 'flushed' at 40k.

 

[iownabuick]

That is great to hear. It really does make a night and day difference. when i did fluid change at 40k [planning either 65k or 70k on next flush, depending if i feel the shifts again like before], it really needed it and was black as well. I did an entire flush. For you, since just drain and fill, id give it 15k miles or so and drain and fill again since it isnt too hard to do. that will help clean out more of the old fluid. might be able to get that slight clunk out.

Might not hurt to do a tcm reset/relearn since not original owner. different driving styles may be logged and previously learned.