Sorry for the long post. I have a 2018 Impala LT2 with 3.6L V6 engine paired with what I’ve researched to be the 6T70 Gen 2.
I’ve started having what I believe to be transmission issues that I’m not entirely sure about.
July 22 - Harsh shift when trying to pass on the highway.. was doing about 50 and hit the accelerator and the entire car shook with a great bang with what I believe is a harsh shift. Lined out after that. Drove from Wichita, KS back to Texas with no more issues.
Another harsh shift cropped up at about 55 mph when I attempted to pass someone 4 weeks later. Within a couple weeks my car started to develop hesitation on slight inclines around 1300-1800 RPM. No noticeable jumps in rpm.
Since then I noticed a hard shift at lower speeds around 20-25 mph. I put a single tube of Lubegard Shudder Fix in the transmission, and changed my air filter which was dirty.
Since then I no longer have harsh shifts, but in third gear at low to moderate rpm’s the car will sometimes jerk/buck(front back motion) slightly like it’s hesitating in third gear and then sometimes it bumps when the shift to 4th completes. Other times it won’t do it at all.At 2,000+ rpm’s the car doesn’t do it at all and shifts fine through all gears. I put the car in manual gear select, and all shifts work fine, but in third gear at low rpm it sometimes hesitates, and when I select 4th gear it bumps sometimes, but not others.
I got my engine oil changed 5 days ago and the jerk started happening more infrequently, but still happens. I’m very confused by this given it’s engine oil and not trans fluid.
Car has 145,500 miles on it. Trans fluid looks normal with no specks/debris on dipstick, and was changed about 15-20,000 miles ago.
I’ve thought about throwing another shudder fix in it to see if it helps.
Does anyone have any thoughts on what this may be? Fixes? Thanks for reading.
I’ve started having what I believe to be transmission issues that I’m not entirely sure about.
July 22 - Harsh shift when trying to pass on the highway.. was doing about 50 and hit the accelerator and the entire car shook with a great bang with what I believe is a harsh shift. Lined out after that. Drove from Wichita, KS back to Texas with no more issues.
Another harsh shift cropped up at about 55 mph when I attempted to pass someone 4 weeks later. Within a couple weeks my car started to develop hesitation on slight inclines around 1300-1800 RPM. No noticeable jumps in rpm.
Since then I noticed a hard shift at lower speeds around 20-25 mph. I put a single tube of Lubegard Shudder Fix in the transmission, and changed my air filter which was dirty.
Since then I no longer have harsh shifts, but in third gear at low to moderate rpm’s the car will sometimes jerk/buck(front back motion) slightly like it’s hesitating in third gear and then sometimes it bumps when the shift to 4th completes. Other times it won’t do it at all.At 2,000+ rpm’s the car doesn’t do it at all and shifts fine through all gears. I put the car in manual gear select, and all shifts work fine, but in third gear at low rpm it sometimes hesitates, and when I select 4th gear it bumps sometimes, but not others.
I got my engine oil changed 5 days ago and the jerk started happening more infrequently, but still happens. I’m very confused by this given it’s engine oil and not trans fluid.
Car has 145,500 miles on it. Trans fluid looks normal with no specks/debris on dipstick, and was changed about 15-20,000 miles ago.
I’ve thought about throwing another shudder fix in it to see if it helps.
Does anyone have any thoughts on what this may be? Fixes? Thanks for reading.
