# Hurst dual won't stay in 1st gear



## Edtyrol (Dec 21, 2021)

Just got my 67 convertible back from some restoration work. I continue to have a problem with the Dual Shift on the TH400. It goes into 1st gear ok, but then shifts automatically into 2nd. I always thought the idea was to be able to upshift when desired. It does stay in 2nd and shifts to 3rd only when moving the shifter up the next detent. Anyone else heard of this problem and possible fixes?


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## PontiacJim (Dec 29, 2012)

Edtyrol said:


> Just got my 67 convertible back from some restoration work. I continue to have a problem with the Dual Shift on the TH400. It goes into 1st gear ok, but then shifts automatically into 2nd. I always thought the idea was to be able to upshift when desired. It does stay in 2nd and shifts to 3rd only when moving the shifter up the next detent. Anyone else heard of this problem and possible fixes?


Your TH-400 may not be original? The GTO and other HP cars got a TH-400 that the factory altered. The trans has a specific 2 letter code that denoted this.

Could be other issues as well if it is the original trans. 

Easy enough to have a trans shop install a "shift improver" kit that will get you what you want if the trans is not original. I have used the Trans-Go in my brother's Mopar 904 and it worked fine - has different levels of firmness also. I think B&M still makes them. NAPA used to offer their brand back in the 1980's and I have used those.


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## LATECH (Jul 18, 2018)

This is how I recalibrate shift points









K018 - TH250 TH350 TH400 TH700-R4 Governor Springs & Weights Shift Kit


TH250 TH350 TH400 TH700-R4 Governor Springs & Weights Shift Kit




transpartswarehouse.com


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## LATECH (Jul 18, 2018)

Heavier weights produce earlier shifts, lighter weights produce later shifts. Stiffer springs tend to produce earlier closely stacked shifts, weaker springs tend to raise and spread apart shift points. As a general rule, the weight selection tends to bring the shift points into the general desired range. The springs then adjust the shift points more precisely to match your vehicle’s performance to your driving preference. Always make changes one step at a time, first to the weights and then to the springs. Note the amount of change in your full throttle shift points, after each weight and/or spring change. Determine from this test which direction the next change, if any, should take. Repeat until the desired shift points are attained. Bear in mind that this installation may require a few tries before the optimum vehicle shift points are attained. If the shift points do not fall into place on the first couple of tries, do not be alarmed. There are hundreds of combinations possible using the supplied weights and springs, therefore your optimum combination exists and is a matter of finding it through trial and error. It is possible to raise your shift points even higher by using a single inner weight and spring. There should always be both the heavy outer weights installed, but the use of one inner weight and spring will permit more versatility and higher shift points.


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## LATECH (Jul 18, 2018)

If your car shifts into second from first seemingly early most of the time, this kit will help a lot. 
The governor will overide manual selection and can overide pretty early on many mid seventies transmissions IIRC. They did that to help prop up fuel mileage.It didnt work ...LOL


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## LATECH (Jul 18, 2018)

Last one I did was a 70 chevelle with a T 350
Guy was pretty happy with it when I was done


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## michaelfind (Dec 14, 2018)

I think the linkage may simply need to be adjusted. Can you keep it in first gear using the “hers” side?


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## lust4speed (Jul 5, 2019)

Probably as simple as a misadjusted cable - especially if it worked before the restoration. Basically the shifter isn't pulling the cable back far enough to select first. The shifter and cable only have the trans selector pulled back into second, and the result is a 1-2 shift while the shifter appears to be in first, but is actually in the second gear notch.

The park position is twice as wide as the gear spacing, and if the cable is adjusted from the park side many times it won't reach first gear. The solution is to disconnect the cable shift pin from the trans lever and place both the Hurst shifter and the trans lever in low and then adjust the cable where the cable pin slides in the lever hole without binding.


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## Edtyrol (Dec 21, 2021)

Man, first time I figured out how to use the forum and I get a flood of helpful answers. I really appreciate them all. My street is under construction right now (I'm in a cup-de-sac) and I can't get her out to test a couple of things. You guys are way above my pay grade on this, but I have access to guys who can get 'er done. Thanks.


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## BLK69JUDGE (Jun 10, 2010)

very common problem when the correct shift cable is not used...
there are several similiar cables that look the same 
but are different lengths and have different pulling/pushing distances 

many guys are happy using the shiftworks cable ...

the transmission pan bracket should look un altered and not bent
also you have the adjustment at the end of the cable at the trans 
if you have the original bracket
sometimes going to the 69 up forward bracket helps


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