4L80E lost 2nd gear
#21
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Man I hate hearing of broken 4l80e tranies. I guess anything mechanical can break though good luck removing and replacing the trans at least youre builder seems to be an honest one.
#30
This one was supposed to be good to 900rwhp. I think the 1-2 shift was set too firm, which is what causes the intermediate sprag to break or roll over. Probably would have been just fine with a softer 1-2 shift. I was reading last night that in 1st gear the intermediate sprag is traveling at 84% of the input shaft RPM, in the opposite direction. On the 1-2 shift it has to bring a 14 lb drum to a complete stop in a fraction of a second. When the 1-2 shift is too firm (too quick) you are counting on a small sprag to do too much.