So where do I start?

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coachdtierney54

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First, I apologise in advance if I'm posting this in the wrong area.

I have a 1985 C30 with a 454. It's stuck in a forward gear (not sure which one). I'm ready to buy a rebuild kit, but my friend thinks the problem might not be within the transmission. He's not around to ask at the moment so I thought I would seek some advice here. What other issues might cause my tranny to stick? The fluid level seems good, and the color is red. What do you think?

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twinturbo427

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Need More info
Assuming it is a TH400 trans, the place to start would be the shift linkage. Then when you have verified that the column linkage is acting in conjunction with the transmission, pull the pan and inspect the internal linkage.
What were you doing when it "got stuck in a forward gear" ?
Smokey burnouts?
5 grand neutral drop?
Power shifting full throttle from reverse to drive?
Or casually accelerating from a stop light? :rolleyes:
 

silverscottsk10

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Is this while driving or stationary?
If stationary, Check shift linkage, comes out of the firewall and down, if the pin has fallen out, it can slip out of the cage and trans won't shift from the steering column, as far as being internal, that's more for @HotRodPC to diagnose

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silverscottsk10

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Need More info
Assuming it is a TH400 trans, the place to start would be the shift linkage. Then when you have verified that the column linkage is acting in conjunction with the transmission, pull the pan and inspect the internal linkage.
What were you doing when it "got stuck in a forward gear" ?
Smokey burnouts?
5 grand neutral drop?
Power shifting full throttle from reverse to drive?
Or casually accelerating from a stop light? :rolleyes:
I have been beat to the reply lol

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Honky Kong jr

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Need More info
Assuming it is a TH400 trans, the place to start would be the shift linkage. Then when you have verified that the column linkage is acting in conjunction with the transmission, pull the pan and inspect the internal linkage.
What were you doing when it "got stuck in a forward gear" ?
Smokey burnouts?
5 grand neutral drop?
Power shifting full throttle from reverse to drive?
Or casually accelerating from a stop light? :rolleyes:
I sure hope if it was doing Smokey burnouts there is an accompanying video.....
 

twinturbo427

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The pic from the muffler post shows a TH400 pan.
I have never seen a TH400 stuck in a gear that wasn't related to linkage, or the internal linkage. I can't remember what it is called (the gate?)
Now, if it was able to be cycled to park reverse neutral but only had one forward gear, that is a different story.
 

Honky Kong jr

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The internal linkage may have come off. You know the nail fell out.
 

4WDKC

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Or casually accelerating from a stop light? :rolleyes:

Surely he would be trying to get good mpg from his truck.


With the engine off, disconnect the linkage to the transmission and see if you can move it. If it moves without the shifter connected to the tranny I would check all the linkage for the bind and not tear apart the transmission. If the transmission is still bound probably will have to come out.
 

coachdtierney54

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I wasn't doing anything crazy. The tranny did not want to shift in colder weather. Had to let the engine get hot and then really had to revise the engine to go anywhere. It gradually got worse and now it's stuck in gear. The last time I drove it I lost reverse. I started it yesterday when it was warmer weather hoping for different results. Went to reverse - nothing. When I went into drive it felt like something broke. The shifter lever was very loose.

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coachdtierney54

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That should have said rev the engine

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twinturbo427

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Engine OFF, Chock the wheels, set the emergency brake, and have someone move the shifter while you inspect the action from the underside. If everything moves from the column to the tranny, it is time to drop the pan.
This step may seem futile but if it is a simple fix and you had spent a weekend benchpressing a TH400, you'll wish you had removed the pan.
 

coachdtierney54

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So what kind of parts should I be looking to replace if I do not have to do a rebuild? I'm on rockauto.com and there's not much to choose from regarding linkage for an automatic transmission.

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coachdtierney54

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Just got the truck back from the garage. I'm back to driving again.

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coachdtierney54

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I had a small leak in the transmission. I fried it. Had to get it rebuild.

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