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**mattfranklin** · 06-14-2018, 07:06 PM

I had a problem once with a vacuum line leaking on a TH400, but that caused high-revving shift problems at part throttle, too.

06-14-2018, 07:06 PM	#4
mattfranklin Senior Member Join Date: Dec 2011 Location: Moraga, CA Posts: 801	Re: th400 won't 2-3 upshift at WOT I had a problem once with a vacuum line leaking on a TH400, but that caused high-revving shift problems at part throttle, too. __________________ (Very) Slow-Going Build Thread: Stock 1970 Short Step with Stock 1970 LT-1 http://67-72chevytrucks.com/vboard/s...d.php?t=567340