Truck won't shift - The 1947 - Present Chevrolet & GMC Truck Message Board Network

justinburnett · 10-15-2010, 10:46 AM

I recently pulled the engine to change the flex plate. See thread: http://67-72chevytrucks.com/vboard/s...d.php?t=425605

Got everything put back together, and it's running fine, but I started to go to work and the transmission's not shifting. It'll go into reverse, drive, neutral, park, but when driving it won't shift out of first. What controlls the shifting, and what could I have messed up that would be causing this? I was so excited that I finished the job and now it seems I didn't do as good as I thought.

MTCK · 10-15-2010, 11:01 AM

Check the vacuum line that goes to your modulator on the transmission. No vacuum makes it think you are at wide open throttle so it holds first.

justinburnett · 10-15-2010, 11:43 AM

is there any way you could show me a picture or diagram or something, or describe where it hooks up to what? I'm about the farthest thing from a mechanic that there is. I'm just driven into it by poverty and desperation.

I was pretty excited when it ran after I put the engine back in. Didn't have a hell of a lot of expectations since I didn't know what I was doing at all when I started.

Moostifer · 10-15-2010, 11:52 AM

line goes from here to carb...

MTCK · 10-15-2010, 12:12 PM

Good deal - beat me to it. So it's a hard line with rubber ends on it, goes from the nipple pointed towards the back of the truck (that is a th350, not sure which trans you have) and runs up to the back of the intake where it either plugs into the intake or the carb. Good luck, and nice work with the R&R on the flywheel!

justinburnett · 10-15-2010, 12:19 PM

Thank you very much. Just came out from under the truck, and sure enough, that hose was popped off the nipple. Forgot to pull that line when I pulled the engine and it got stretched a little tight before I noticed it an disconnected it. Can't test it yet, wife's left me with 3 kids this morning (speaking of which, how hard would it be to put 4 seatbelts across the bench instead of 3?), but I should be able to get out there within a few hours and check. Pretty confident that's the problem though.

Adams74Chevy · 10-15-2010, 12:59 PM

Quote:

Originally Posted by justinburnett

(speaking of which, how hard would it be to put 4 seatbelts across the bench instead of 3?), but I should be able to get out there within a few hours and check. Pretty confident that's the problem though.

Don't do it seat belts are a fed. safety law.

justinburnett · 10-15-2010, 02:35 PM

Oh that's crap. I want to take my wife and two kids out boating without bringing the second car. Oh well.

Took it out for a spin and it shifts great. No more problems! Thanks!

Slonaker · 10-15-2010, 04:18 PM

Don't feel bad. I did the same thing he second time I pulled my trans out. By then I should have known better.

Glad to hear you got everything working.

Slonaker

10-15-2010, 10:46 AM	#1
justinburnett Registered User Join Date: Sep 2010 Location: The Dalles, OR Posts: 392	Truck won't shift I recently pulled the engine to change the flex plate. See thread: http://67-72chevytrucks.com/vboard/s...d.php?t=425605 Got everything put back together, and it's running fine, but I started to go to work and the transmission's not shifting. It'll go into reverse, drive, neutral, park, but when driving it won't shift out of first. What controlls the shifting, and what could I have messed up that would be causing this? I was so excited that I finished the job and now it seems I didn't do as good as I thought.

10-15-2010, 11:01 AM	#2
MTCK Registered User Join Date: Dec 2009 Location: Fairbanks, AK Posts: 1,830	Re: Truck won't shift Check the vacuum line that goes to your modulator on the transmission. No vacuum makes it think you are at wide open throttle so it holds first. __________________ -Marcus 1991 V3500 L29 454 4L80E NP205 D60/14 Bolt 4.56's 1984 K30 292 TH400 NP205 D60/14 Bolt 4.56's flat bed 7'6" Meyer Plow 2022 Silverado 3500 L8T Project Daily Driver Project Heavy Hauler Project Plow Truck

10-15-2010, 11:43 AM	#3
justinburnett Registered User Join Date: Sep 2010 Location: The Dalles, OR Posts: 392	Re: Truck won't shift is there any way you could show me a picture or diagram or something, or describe where it hooks up to what? I'm about the farthest thing from a mechanic that there is. I'm just driven into it by poverty and desperation. I was pretty excited when it ran after I put the engine back in. Didn't have a hell of a lot of expectations since I didn't know what I was doing at all when I started.

10-15-2010, 11:52 AM	#4
Moostifer a fool with no money Join Date: May 2005 Location: Overton, Tx Posts: 532	Re: Truck won't shift line goes from here to carb... __________________ Basicly stock 83 SWB with a few Bolt-ons before, during and still during http://photobucket.com/albums/y251/moostifer/truck/ http://photobucket.com/albums/y251/moostifer/motor/

10-15-2010, 12:12 PM	#5
MTCK Registered User Join Date: Dec 2009 Location: Fairbanks, AK Posts: 1,830	Re: Truck won't shift Good deal - beat me to it. So it's a hard line with rubber ends on it, goes from the nipple pointed towards the back of the truck (that is a th350, not sure which trans you have) and runs up to the back of the intake where it either plugs into the intake or the carb. Good luck, and nice work with the R&R on the flywheel! __________________ -Marcus 1991 V3500 L29 454 4L80E NP205 D60/14 Bolt 4.56's 1984 K30 292 TH400 NP205 D60/14 Bolt 4.56's flat bed 7'6" Meyer Plow 2022 Silverado 3500 L8T Project Daily Driver Project Heavy Hauler Project Plow Truck

10-15-2010, 12:19 PM	#6
justinburnett Registered User Join Date: Sep 2010 Location: The Dalles, OR Posts: 392	Re: Truck won't shift Thank you very much. Just came out from under the truck, and sure enough, that hose was popped off the nipple. Forgot to pull that line when I pulled the engine and it got stretched a little tight before I noticed it an disconnected it. Can't test it yet, wife's left me with 3 kids this morning (speaking of which, how hard would it be to put 4 seatbelts across the bench instead of 3?), but I should be able to get out there within a few hours and check. Pretty confident that's the problem though.

10-15-2010, 02:35 PM	#8
justinburnett Registered User Join Date: Sep 2010 Location: The Dalles, OR Posts: 392	Re: Truck won't shift Oh that's crap. I want to take my wife and two kids out boating without bringing the second car. Oh well. Took it out for a spin and it shifts great. No more problems! Thanks!

10-15-2010, 04:18 PM	#9
Slonaker Insert Witty Text Here Join Date: Oct 2002 Location: San Antonio, TX Posts: 3,415	Re: Truck won't shift Don't feel bad. I did the same thing he second time I pulled my trans out. By then I should have known better. Glad to hear you got everything working. Slonaker __________________ '86 Chevy C10 (Sold 04/19/13 ) Stock '01 Silverado



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