2017 Acadia Denali slips shifting from 2nd to 3rd 50% of the time. Two trips to the dealer and one to a transmission shop. It doesn’t do it for them, so they say there is nothing wrong. Anyone else have this; or, does anyone have any information on a transmission monitoring option?
How do you know this? Is this just from your feel?
There is no better tool I can suggest for you to monitor your car than the ones the dealer and the trans shop uses. They cost $6000 or so and require a subscription plus many hours of training to learn how to use.
You’ve had 3 professionals that own those tools monitor the transmission while it operates. I’d suggest that since the folks with the tools all agree your trans is operating OK… it IS indeed operating OK.
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Mustangman, Thank you for your response. I do appreciate it.
I’ll be the first to admit I know almost nothing about transmissions. Hence why I am on here; and, why I took it to 3 “professionals”. I do know that when the truck is accelerating and it shifts from 2nd to 3rd, the tachometer will jump from around 2500 RPMs to around 4000 RPMs and I will lurch forward in my seat as the truck has stopped accelerating. Maybe that’s normal and it is operating “OK”. I do know the transmission shop simply took my truck for a 5-minute drive…I don’t think any tools were involved. The dealership told me “they put 12 miles” on my truck and didn’t notice anything…they did not mention any tools or readouts from a tool…just 12 miles.
If you know the name of any of the $6,000 tools, I’d be happy to call around and ask for a shop to put my truck on it. I’m willing to pay for a diagnosis as the drivetrain is still under warranty. But if the “professionals” cannot or will not see the issue, there’s not much hope that I will get them to fix it.
Does this shift flare only occur when the transmission is cold?
Mostly…but not always. Sometimes when the truck is already warm. It really is random. I don’t think I have ever noticed it when really accelerating hard.
Since the problem occurs more often when cold, have you left the vehicle for several days to be driven in the mornings?
The dealership had my truck for an entire week to supposedly check it in the mornings. The transmission shop doesn’t do that. They only scan it for codes and drive it while you wait.
Ever had the transmission fluid changed? That could help.
If the trans slips, a code should be set. I think P0896 is the code for “shift time too long”. I have a Buick that will set that code, then the computer raises the line pressure (to prevent further slipping) and the trans will begin to shift hard. I do not get a check engine light when the code is set. Apparently, our local Autozone’s scanner will read the code, as that’s where I first learned the Buick had that code when I was getting a different code read for a separate issue. Obviously, my old Buick is less advanced than your Acadia seeing as the Buick is an 05 model. So, I’d tend to think your 17 model’s computer would surely detect the slippage. Hence, I understand why the trans shop is scanning it for codes. They should definitely still drive it, though. Have you tried getting them or the dealer to ride with you as you drive the vehicle and demonstrate when the issue happens?
Did this issue just start happening or has it always done it? Some of the newer multi speed automatics, the torque converter will lock in certain gears and it feels like a gear shift but it really isn’t. I owned a 2013 F150 with a six speed auto. The torque converter would lock in 3rd gear and it felt like an oddball transmission shift. The large surge in engine rpm that you’re describing doesn’t sound like normal operation, though. However, I’ve never driven a newer Acadia.
Thank you for the response. It’s been happening for about 6 months or so. The first time the dealer did find a service advisory and replaced “upper and lower valve body” and “reset transmission adaptives”.
I have not, but good call. I’ll get that done. Thanks!