4L70e VERY hard shift 1-2 and 2-3
#1
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This is in my 2007 vortec max truck. 6.0 L76, 4L70E.
What could cause a 4L70E to shift extremely hard? Everything is stock, 109,000 miles. Even the downshift is much a much harder shift than normal. It will shift violently hard even if I'm creeping along at 30 mph off the gas. This just started happening the past couple days. It also just started making a "clunk" sound when putting it into drive.
What could cause a 4L70E to shift extremely hard? Everything is stock, 109,000 miles. Even the downshift is much a much harder shift than normal. It will shift violently hard even if I'm creeping along at 30 mph off the gas. This just started happening the past couple days. It also just started making a "clunk" sound when putting it into drive.
#4
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As suggested the line pressure is probably being commanded high. You should get it scanned to see why.
Is your service engine soon lamp on? Has it been tuned recently or do you have any sort of a "chip" on it?
g
Is your service engine soon lamp on? Has it been tuned recently or do you have any sort of a "chip" on it?
g