Help! th350 wont shift from 1st to 2nd - The 1947 - Present Chevrolet & GMC Truck Message Board Network

As2rd · 01-13-2008, 05:08 PM

Im trying to sell my truck so I can get something that suits what i need. I know waah but the truck is acting up whenever someone wants to test drive it. The last guy who was looking at it is interested in purchasing it if i get the tranny fixed. The thing is, I dunno whats going on. I replaced the fluid, changed the filter, replaced the mod, the vacuum line, and the fluid is at perfect level and is red.

I think that i let the truck sit too long, because of the weather, and the fluid isnt circulating. Anyone have an idea or solution? All input is welcome.

tsetsaf · 01-13-2008, 07:56 PM

-Check your kickdown linkage
-Check the shifter linkage to make sure it is operating smoothly and properly
-Drive it around a bit before the next buyer stops by to loosen up the bands.

Is it slipping or just not shifting?
Slipping = bad
Not Shifting = fixable

matthufham · 01-13-2008, 08:11 PM

whenever mine doesnt shift or has a delayed shift time i know my vacuum line is kinked, cut, or damaged. 5 out of 5 times it's been my suspect.

As2rd · 01-13-2008, 08:45 PM

Thanks for replying. The trans. is not slipping, its just not shifting to second on its own.

Ill try to mess with the linkage and the vacuum hose. Luckily the guy gave me a month to figure it out.

*Billla* · 01-14-2008, 02:43 PM

Quote:

Originally Posted by matthufham

whenever mine doesnt shift or has a delayed shift time i know my vacuum line is kinked, cut, or damaged. 5 out of 5 times it's been my suspect.

That's what it's always been for me too - finally put a small hose clamp on the line at the modulator. Try starting in low and shifting it manually up - if it'll shift manually, then IMHO that's the first place to double check.

Premium72 · 01-13-2008, 08:54 PM

this is the only problems ive ever had from any tranny(lucky me) its allways the vacume like. always. check it out.

huero · 01-13-2008, 09:01 PM

If, it is not in the linkage. Then, you have internal problems. Happened to a 70 Nova I had years ago. Installed a rebuilt trans and had that same problem. Lucky trans came with a warrenty.

As2rd · 01-13-2008, 09:09 PM

Thats what im afraid of. If it is internal, I might as well not sell it. I cant wait til i build my next one.

chuck1960 · 01-14-2008, 02:27 PM

Check the govenor, it probably has the teeth stripped off. It will be at the back of the trans with a round cover and a clip over it. If it's bad the trans will not shift out of low gear

HavinSomeFun · 01-14-2008, 02:38 PM

also check the modulator, thats what the vac hose goes 2.

01-13-2008, 05:08 PM	#1
As2rd Registered User Join Date: Feb 2007 Location: Lexington Park, MD Posts: 47	Help! th350 wont shift from 1st to 2nd Im trying to sell my truck so I can get something that suits what i need. I know waah but the truck is acting up whenever someone wants to test drive it. The last guy who was looking at it is interested in purchasing it if i get the tranny fixed. The thing is, I dunno whats going on. I replaced the fluid, changed the filter, replaced the mod, the vacuum line, and the fluid is at perfect level and is red. I think that i let the truck sit too long, because of the weather, and the fluid isnt circulating. Anyone have an idea or solution? All input is welcome. __________________ 1972 Chevy Truck 350ci/th350 Auto. Daily Driver

01-13-2008, 07:56 PM	#2
tsetsaf Registered User Join Date: Dec 2007 Location: Southern CA Posts: 210	Re: Help! th350 wont shift from 1st to 2nd -Check your kickdown linkage -Check the shifter linkage to make sure it is operating smoothly and properly -Drive it around a bit before the next buyer stops by to loosen up the bands. Is it slipping or just not shifting? Slipping = bad Not Shifting = fixable

01-13-2008, 08:11 PM	#3
matthufham Registered User Join Date: Feb 2005 Location: Carl Junction, Missouri Posts: 2,061	Re: Help! th350 wont shift from 1st to 2nd whenever mine doesnt shift or has a delayed shift time i know my vacuum line is kinked, cut, or damaged. 5 out of 5 times it's been my suspect.

01-13-2008, 08:45 PM	#4
As2rd Registered User Join Date: Feb 2007 Location: Lexington Park, MD Posts: 47	Re: Help! th350 wont shift from 1st to 2nd Thanks for replying. The trans. is not slipping, its just not shifting to second on its own. Ill try to mess with the linkage and the vacuum hose. Luckily the guy gave me a month to figure it out. __________________ 1972 Chevy Truck 350ci/th350 Auto. Daily Driver

01-13-2008, 08:54 PM	#6
Premium72 Registered User Join Date: Sep 2005 Location: Villa Rica Ga Posts: 889	Re: Help! th350 wont shift from 1st to 2nd this is the only problems ive ever had from any tranny(lucky me) its allways the vacume like. always. check it out. __________________ WombatFire, Art-Design-MADNESS Follow My Build and Adventures on Instagram

01-13-2008, 09:01 PM	#7
huero 1969 Short, Fleet, and Beat Join Date: Apr 2007 Location: Long Beach, Ca. Posts: 867	Re: Help! th350 wont shift from 1st to 2nd If, it is not in the linkage. Then, you have internal problems. Happened to a 70 Nova I had years ago. Installed a rebuilt trans and had that same problem. Lucky trans came with a warrenty.

01-13-2008, 09:09 PM	#8
As2rd Registered User Join Date: Feb 2007 Location: Lexington Park, MD Posts: 47	Re: Help! th350 wont shift from 1st to 2nd Thats what im afraid of. If it is internal, I might as well not sell it. I cant wait til i build my next one. __________________ 1972 Chevy Truck 350ci/th350 Auto. Daily Driver

01-14-2008, 02:27 PM	#9
chuck1960 Junior Member Join Date: Oct 2005 Location: cleveland, tn. Posts: 71	Re: Help! th350 wont shift from 1st to 2nd Check the govenor, it probably has the teeth stripped off. It will be at the back of the trans with a round cover and a clip over it. If it's bad the trans will not shift out of low gear

01-14-2008, 02:38 PM	#10
HavinSomeFun Still Just Havin Some Fun! Join Date: Jun 2007 Location: Piedmont, Oklahoma Posts: 1,145	Re: Help! th350 wont shift from 1st to 2nd also check the modulator, thats what the vac hose goes 2. __________________ a green one with some stuff done to it....



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