Hi all,

I have a 2017 Suburban and downshifting 3>2 is hard and not smooth - hard enough to be a big concern for me. When I am in AUTO (D on the tree) This happens sporadically and I cannot reproduce on demand in automatic.
If I switch to manual (M on the tree), I can reproduce over and over.
Travelling at 60-80 kph I shift into manual.....I am usually making sure I am going fast enough to be in 3rd gear. Then I manually downshift to 2nd. I get a big bump and a sudden engine rev.
ALL OTHER GEAR SHIFTS ARE FINE......In all other gears, in manual, the computer revs the engine automatically to match the transmission rpms for a smooth shift...doesn't happen specifically for 3>2 downshift.

I have taken to the dealer almost every 2 weeks for about 8 months
Replace Tranny computer and hydraulic parts - cant remember which. Change fluids etc.....Lots of work was done - Warranty bills equal approx 5k CAD so I know there did try and fix.
I opened a case with GM Canada - the final word was that "although this is not pleasant, this is normal expected behavior" WTF!!!!!!!!!!

The dealer finally said to me that I should seek out other people with the exact same truck as mine and see if they have the same issue/behavior..... Not an easy task!

So I have come here to the forums for help!

There have to be a few 2017 Suburban owners on the forums - I would really appreciate it if any 2017 owners could help me out and try this and post your findings here....Please do the test and let me know if you have the same issues.

My specs are:
2017 Suburban LT Black
My particular model is a 4 Wheel Drive powered by a 5.3L V-8 VVT DI with Active Fuel Management (L83) mated to a GM 6L80 transmission.

Thank you in advance. I would love to be able to go back to GM Canada with 200 people that have the same issues.

--sam

 

I have same issue with same car, dealer say it is normal

 

So about four months ago, my transmission died and I had to get it rebuilt.
The funny thing is after the rebuilt I'm still getting a hard downshift. I did not get it rebuilt at the dealer. I got it rebuilt at an independent.
The fact that it's still shifting hard specifically for second gear tell me that there's something else going on.

Could it be that there's some grounding happening on the engine which is messing with the computer? I don't know what else to do at this point. It's so frustrating.