Author Topic: trany shifts funny  (Read 16577 times)

Offline 1978 454 Big 10

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Re: trany shifts funny
« Reply #15 on: January 15, 2012, 02:09:25 pm »
Not sure if the 87' 400 has a lockup torque converter, but that sounds like what they do when they go out.
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Offline 87suburban

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Re: trany shifts funny
« Reply #16 on: January 15, 2012, 02:26:06 pm »
you mean the converter going bad?

Offline 1978 454 Big 10

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Re: trany shifts funny
« Reply #17 on: January 15, 2012, 02:34:47 pm »
If the 87' 400 uses a lockup converter, I would check the relay/switch that controls it locking up.
1978 Chevy C-10 Silverado "Big 10" 454, 400 turbo, PW, PDL, Tilt, Cruise, AM/FM, Factory Tach, Dual Tanks, Locking Diff, Sliding Rear Window, Trans Cooler, Cordova Brown/Santa Fe Tan. 052,600 Original miles!

Offline 87suburban

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Re: trany shifts funny
« Reply #18 on: January 15, 2012, 03:07:15 pm »
if my tranny had a lock-up converter, wouldnt it have more than one wire hooking up to the tranny? cause on mine i only have the one wire that hooks up to a detent solenoid on the driver side of the tranny, toward the rear of the tranny.

Offline VileZambonie

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Re: trany shifts funny
« Reply #19 on: February 05, 2012, 03:34:07 pm »
You do not have a lock up torque converter. Replace the vacuum modulator and adjust it to your liking. Make sure the vacuum hose connection is tight and no vacuum leaks.
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Offline 87suburban

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Re: trany shifts funny
« Reply #20 on: February 05, 2012, 08:17:04 pm »
the modulator is only bout a year old, cause i had the trany rebuilt just bout a year ago. unless the new modulator could have be defective from the manufacturer. but i tried to adjust it, but it didnt make any difference. just wondering, if its not gettin enough vacuum could that cause it to jump between 2nd an 3rd?

Offline 87suburban

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Re: trany shifts funny
« Reply #21 on: February 15, 2012, 08:11:40 pm »
got another question. im my quest to find a 700R4, does it make a difference if it was bolted to a gas engine or diesel?

Online Captkaos

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Re: trany shifts funny
« Reply #22 on: February 22, 2012, 05:58:02 pm »
Doesn't matter as far as Transmission goes, but the torque converter isn't the same.

Offline 87suburban

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Re: trany shifts funny
« Reply #23 on: February 22, 2012, 07:12:29 pm »
ok wasnt sure if there was some strange difference, i know the converters have a lower stall than gas converters. now what kind of cluster would i have to take a 700R4 that was for a two-wheel drive an set it up for a 4x4? would that become a huge headache?