93 automatic c1500 silverado

ksaln · 12-01-2008, 11:39 AM

what would be the cause for hard shifting out of first gear? when I back off the gas it will shift in correctly however if i keep the gas petal down it hard shifts.

**manic** · 12-01-2008, 02:12 PM

Sounds like a vaccum thing to me..Does it shoot out black smoke on
fast acceleration?

**SABL** · 12-01-2008, 08:24 PM

I'll check it out in the AM..... I should have the manual in my garage for that tranny.

It does sound like a vacuum modulator or the corresponding hose to it.

**SABL** · 12-03-2008, 06:52 AM

Sorry for the delay.

The book says:
check fluid level
check vacuum hose at modulator and entire lenght
check all vacuum hoses and source

The modulator will be mounted on the side of the tranny and can be identified by the rubber vac hose attached.

Let us know how it goes, there are other things that can cause this symptom. But, I would check the vac line first.

Haynes does publish a book for your tranny....Techbook #10360

SABL

12-01-2008, 11:39 AM	#1 (permalink)
ksaln Registered User Join Date: Dec 2008 Posts: 1 OS: xp	93 automatic c1500 silverado what would be the cause for hard shifting out of first gear? when I back off the gas it will shift in correctly however if i keep the gas petal down it hard shifts.

12-01-2008, 02:12 PM	#2 (permalink)
manic Mod Hardware Team Join Date: Aug 2005 Location: Florida Posts: 5,240 OS: xp	Re: 93 automatic c1500 silverado Sounds like a vaccum thing to me..Does it shoot out black smoke on fast acceleration? __________________

12-01-2008, 08:24 PM	#3 (permalink)
SABL Moderator Relaxation Room Join Date: Jul 2008 Location: Galena, Ohio Posts: 1,219 OS: WinXP SP3	Re: 93 automatic c1500 silverado I'll check it out in the AM..... I should have the manual in my garage for that tranny. It does sound like a vacuum modulator or the corresponding hose to it.

12-03-2008, 06:52 AM	#4 (permalink)
SABL Moderator Relaxation Room Join Date: Jul 2008 Location: Galena, Ohio Posts: 1,219 OS: WinXP SP3	Re: 93 automatic c1500 silverado Sorry for the delay. The book says: check fluid level check vacuum hose at modulator and entire lenght check all vacuum hoses and source The modulator will be mounted on the side of the tranny and can be identified by the rubber vac hose attached. Let us know how it goes, there are other things that can cause this symptom. But, I would check the vac line first. Haynes does publish a book for your tranny....Techbook #10360 SABL