07-18-2012, 10:37 AM
So, I've put just under 2700 miles on my FLT Level 4-4L80E with billet input shaft. It's been running extremely well until the last 100-200 miles. I started noticing that it would carry first gear under part throttle. It'll carry it to 30ish mph, and then shift into second with a very firm shift. It does this in other gears as well. Also, when I put it in reverse, it takes a few seconds to engage. It does this even after being warmed up and driven for a bit. I thought maybe the friction components in the tranny had worn in, and whatever debris might have clogged the filter, creating a low line pressure issue. So, I drained the pan, replaced the filter with an OEM filter, and put new fluid in it.........still the same issue. Any help would be appreciated.