4 L 60 I think, but it'll hard start sometimes, like if I let it sit over night, then go to start it, it'll start right up, if I run it say maybe an hour cut it off, go to crank it 5 min later takes 2 tries, the transmission reverese, 1st second and sometimes 3rd manually, when I put it In drive shifts perfect from 1st to 2nd then I've to get it over 30 mph then it shifts into 3rd no 4th what so ever need help!!!
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