Author Topic: TH350 no second gear???  (Read 7268 times)

Offline zieg85

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TH350 no second gear???
« on: May 02, 2011, 05:39:49 PM »
I have a TH 350 that goes from 1st to 3rd and skips second.  Anyone familiar with TH 350's can shed some light on it.  I'd like to fix it if it is simple.  I can manually shift it from 1st to 2nd, nothing happens and shift to drive and it goes into 3rd, kinda like second isn't there.  I am hoping maybe the valve body has a broken spring however I know nothing about auto transmissions.  Any auto trans experts in the crowd that can shed some light on it???
Carl 
1985 C20 Scottsdale 7.4L 4 speed 3.21
1986 C10 under construction
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Offline bake74

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Re: TH350 no second gear???
« Reply #1 on: May 02, 2011, 05:42:30 PM »
     It sounds to me like the valve body for second gear is stuck not broken, if it is stuck in the open position the fluid would keep going through it to the 3rd gear valve body.  I can ask some of my friends for sure, might take me a day though.
#1: The easiest and most obvious solution to any problem is 99% of the time correct.
#2: There is no such thing as impossible, it just takes longer.
  74 k10, 77k10    Tom

Offline bake74

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Re: TH350 no second gear???
« Reply #2 on: May 02, 2011, 05:48:03 PM »
     Ok actually got ahold of one of my buddies at a transmission shop, he said check external first for proper adjustments, if it is internal, either a valve body or burnt clutches.  Without tearing it apart he said anyone would just be guessing, hope this helps.
#1: The easiest and most obvious solution to any problem is 99% of the time correct.
#2: There is no such thing as impossible, it just takes longer.
  74 k10, 77k10    Tom

Offline zieg85

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Re: TH350 no second gear???
« Reply #3 on: May 02, 2011, 08:29:10 PM »
     Ok actually got ahold of one of my buddies at a transmission shop, he said check external first for proper adjustments, if it is internal, either a valve body or burnt clutches.  Without tearing it apart he said anyone would just be guessing, hope this helps.

Externally I am assuming it is fine as I get the proper P R N D 2 1 action.  It goes in reverse fine as well as all the rest, it just don't have second gear either manually or when the trans is set to drive.  It shifts through second...  Can anyone point to a picture of the valve body (where) I would look into for a sticky valve?  BTW I have an OK downshift if I really take it easy and floor it when it is in 3rd.
Carl 
1985 C20 Scottsdale 7.4L 4 speed 3.21
1986 C10 under construction
https://www.facebook.com/groups/248658382003506/

Offline zieg85

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Re: TH350 no second gear???
« Reply #4 on: May 02, 2011, 08:31:19 PM »
Bake 74, forgot to thank you!!!
Carl 
1985 C20 Scottsdale 7.4L 4 speed 3.21
1986 C10 under construction
https://www.facebook.com/groups/248658382003506/