Author Topic: "Park" in a bind?  (Read 1093 times)

Offline 76LongBox

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"Park" in a bind?
« on: August 19, 2014, 01:27:34 PM »
Hey guys.  I did a little searching and didn't find exactly what I was searching for, so here goes...

I have a 76 GMC 1/2 ton LWB with a new (last year) GM 350 Crate Engine and TCI TH350 transmission.  A while back I had it jumping out of park when parked on the slightest of inclines.  I figured it was just a linkage issue, but wasn't sure exactly what to check, so I've just been putting it "hard" into park and making sure the column shifter feels like it's really in park, and also setting the E-brake.

I decided today to check it out and see if there was any adjustment I could make on the linkage.  I slid under the truck and loosened the set screw on the linkage, and the transmission immediately popped out of park and into reverse - like it was in a bind or something.  I can rotate the C-bracket (if that's the right term) on the transmission back to park, let go, and it'll jump right back to reverse.

Is this normal depending on how things are lined up on the drive train at the time of parking it?

Also, while shifting directly on the transmission by rotating the C-bracket, there are good, positive "clicks" as it goes into each gear.  However, when shifting from the column, it's quite spongy and a little sloppy when in any particular gear.  What causes this?  Worn column, linkage, etc.? Or is this also normal for these old trucks?

Thanks in advance....

Offline zieg85

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Re: "Park" in a bind?
« Reply #1 on: August 19, 2014, 09:45:24 PM »
Check your cab mounts.  I've had them sag and cause that very issue.
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Offline 76LongBox

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Re: "Park" in a bind?
« Reply #2 on: August 19, 2014, 10:05:49 PM »
I was able to adjust the linkage and make the column shifter feel like it's going into park a little more solidly, so hopefully that has fixed my issue.

Offline bake74

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Re: "Park" in a bind?
« Reply #3 on: August 20, 2014, 08:27:56 AM »
I was able to adjust the linkage and make the column shifter feel like it's going into park a little more solidly, so hopefully that has fixed my issue.

      It should be very easy to check the cab mounts as Zeig suggested, if on a incline and your cab looks like it leans, then you probably should check them out a little more deeply.
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