After transmission flush there is a quick two second shifting delay and a jerk

2012 GMC TERRAIN
91,000 MILES • 2.4L • 6 CYL • 4WD • AUTOMATIC
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LESTER.L.HASH
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I went and got a flush, oil change and spark plugs replaced. When I was driving it home after picking it up. It had delayed shifting. Most of it smoothed out but there is a delay in second gear. There no smell no noise and no grinding just a quick 2 second delay and a jerk. Will this smooth out.
Feb 14, 2020 at 2:22 PM
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STEVE W.
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That is hard to say. If it wasn't doing it prior to the flush it is possible that it's a small piece of crud that was moved into a different spot and is now causing a problem. No real way to know for sure what it is without taking the transmission apart and cleaning it out. You might go back and tell the place that did the flush, possibly a second flush might clear it out? This is one of the reasons I would rather do a spill and fill service with a filter whenever possible. Unfortunately on your vehicle that requires the transmission be removed and taken apart to get to the filter so that isn't an easy option.
Feb 14, 2020 at 2:41 PM
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KASEKENNY
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It depends on how harsh this is and if they performed a relearn of the transmission adaptives. This means if they reset the learned shift pattern.

The main cause of this after a service is the fluid is low. I attached the procedure to check the fluid. I would start with that and then ask if they reset the adaptives.

Keep us posted on what they say and if the fluid is low and we can go from there. Thanks
Feb 14, 2020 at 2:41 PM
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ASEMASTER6371
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Good afternoon,

A flush was a bad idea. The additive for flushing does not react well with the clutches and could damage them.

Just changing the fluid and filter is enough.

Roy
Feb 14, 2020 at 2:50 PM