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Russell · 11-14-2005, 02:34 AM

Check the vaccum modulator, the line may have fallen off, or the modulator may have failed all together.

The TH400 will not shift out of 1st gear until the govenor tells it to at a very high rpm if the modulator isn't working properly, and it will be a very hard shift when it does.

11-14-2005, 02:34 AM	#2
Russell Professional Grade Join Date: May 2003 Location: Fort McMurray, Alberta Posts: 7,915	Re: Transmission Help Check the vaccum modulator, the line may have fallen off, or the modulator may have failed all together. The TH400 will not shift out of 1st gear until the govenor tells it to at a very high rpm if the modulator isn't working properly, and it will be a very hard shift when it does. __________________ 1995 Chevrolet 2 Door Tahoe (6.6L LBZ Duramax / ZF6 / NP241 with 1 ton solid axle swap)