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73-87 Chevy _ GMC Trucks => Engine/Drivetrain => Topic started by: zieg85 on December 24, 2013, 02:17:34 pm
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As asked in the subject line, what is the consensus? 1st and 2nd when manually shifted it stays in first, pop it in D and it goes in 3rd. When in drive it goes from 1st to 3rd.
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what color is the fluid and does it smell burnt
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what color is the fluid and does it smell burnt
More red but is a reddish brown. It smells just like fresh ATF
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You might try dropping the valve body to see if your 2-3 shift valve is stuck in the upshift position.
But yeah, check your fluid first. After that pull the modulator to make sure there is no fluid in the vacuum line.
Your governor is ok or you wouldn't get any upshift at all.
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After thought, you have something wrong in your valve body because even in manual 1 the TH400 will upshift after you exceed 20mph.
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If you upshift up to 3rd then manually select 2nd do you get a downshift?
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If you upshift up to 3rd then manually select 2nd do you get a downshift?
I have not tried that but I drive it easy and I find if need a little more "go" it downshifts back into first and the engine RPM's have gone higher than that old truck's engine should...