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Old 09-23-2007, 12:26 PM   #1
Long Roof
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Tranny problems, help!

O.k. I'm feeling a little baffled at the moment. The family and I took the Jimmy out for a drive last night and on our way home we stopped to pic up some food. I waited outside with the engine running and put it in park. When I went to drop it in gear to leave it lurched forward as soon as I moved to the reverse detent. I didn't think much about it at the moment but once we got down the road it wouldn't shift out of 2nd gear. I pulled over to take a look and found out I have no reverse or neutral. We took of down the road again and now I only have 1st. We drove it home and I looked at it this morning in the garage. The shift linkage is just fine. I started it up and as soon as I drop it out of park it wants to go forward. What gives?

The tranny is a rebuilt 350 turbo and it was recently installed by the previous owner.

Any tranny experts have any idea what is going on?
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Old 09-23-2007, 01:40 PM   #2
woodridge
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Re: Tranny problems, help!

I would drop the pan and make sure the manual valve has not come loose from the rooster comb. Seen this happen a few times.
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Old 09-23-2007, 01:53 PM   #3
Longhorn Man
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Re: Tranny problems, help!

that's exactly what I was thinking.
The linkage on the side of the tranny moves a piston in the valve body, it probably just came disconnected. Easy fix, only cost is tranny fluid, and I think a cotter pin. (been a while)
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Old 09-23-2007, 02:08 PM   #4
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Re: Tranny problems, help!

If I drop the pan will it be obvious and in plain sight? I know absolutely nothing about transmissions.

It kind of sounds logical that something just came undone. It worked just fine until we stopped and I put it in park.

Anyone else have any ideas?
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The Good:
- 72 GMC Jimmy 4x4 - 307 cid / 350 th
- 70 Chevy Suburban 1/2T 2wd - 454 cid /400 th
- 96 Chevy Impala SS - mainly stock
- 98 Chevy Tahoe LT 4x4 - all stock
The Bad:
- 86 Chevy Suburban 1/2T 4x4 - winter beater
The Ugly:
- 72 Chevy Suburban 1/2T 2wd - parts truck
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Old 09-23-2007, 02:27 PM   #5
Longhorn Man
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Re: Tranny problems, help!

Disconect the shift rod from the linkage (talkin on the outside of the tranny) then drop the pan, and you'll be able to move the linkage, and see where it isn't hooked up. You'll probably find the pin right on top of the trans filter.
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Old 09-23-2007, 02:34 PM   #6
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Re: Tranny problems, help!

No cotter pin, it's an S shaped link that runs from the comb looking rig to the linkage.
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Last edited by krue; 09-23-2007 at 02:34 PM.
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Old 09-23-2007, 03:16 PM   #7
Longhorn Man
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Re: Tranny problems, help!

cool, thanks for the correction. It's been 5 or 6 years since I had to deal with this.
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Old 09-23-2007, 03:27 PM   #8
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Re: Tranny problems, help!

Look for either the nut that holds the "comb" on the shaft to be loose or the spacer clip that holds the shaft in place to be missing. Either will allow the S link to get out of position and cause the problem.
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Old 09-24-2007, 05:30 PM   #9
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Re: Tranny problems, help!

O.K. guys I dropped the pan and sure enough the nut on the inside of the 'comb' is loose. The comb was actually off the roller on the detent thingy. I didn't see what the s clip was until I looked on top of the filter. There it was with the piston thingy shoved all the way in. That would explain why all I had was 1st. I pulled the piston out and put the 's' clip back where I think it belongs. Can you guys take a real good look at the pictures and let me know if this looks right? If all looks well then I will tighten up the nut and put the pan back on. Thanks for your help.
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The Good:
- 72 GMC Jimmy 4x4 - 307 cid / 350 th
- 70 Chevy Suburban 1/2T 2wd - 454 cid /400 th
- 96 Chevy Impala SS - mainly stock
- 98 Chevy Tahoe LT 4x4 - all stock
The Bad:
- 86 Chevy Suburban 1/2T 4x4 - winter beater
The Ugly:
- 72 Chevy Suburban 1/2T 2wd - parts truck
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Old 09-24-2007, 05:31 PM   #10
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Re: Tranny problems, help!

One more.
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The Good:
- 72 GMC Jimmy 4x4 - 307 cid / 350 th
- 70 Chevy Suburban 1/2T 2wd - 454 cid /400 th
- 96 Chevy Impala SS - mainly stock
- 98 Chevy Tahoe LT 4x4 - all stock
The Bad:
- 86 Chevy Suburban 1/2T 4x4 - winter beater
The Ugly:
- 72 Chevy Suburban 1/2T 2wd - parts truck
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Old 09-24-2007, 07:52 PM   #11
Long Roof
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Re: Tranny problems, help!

Any comments? I'd feel better putting the pan back on if someone would confirm that this looks correct. I've already had the pan off once before and I'd like not to donate any more good trans fluid to the recycler. Thanks
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The Good:
- 72 GMC Jimmy 4x4 - 307 cid / 350 th
- 70 Chevy Suburban 1/2T 2wd - 454 cid /400 th
- 96 Chevy Impala SS - mainly stock
- 98 Chevy Tahoe LT 4x4 - all stock
The Bad:
- 86 Chevy Suburban 1/2T 4x4 - winter beater
The Ugly:
- 72 Chevy Suburban 1/2T 2wd - parts truck
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Old 09-24-2007, 08:01 PM   #12
Longhorn Man
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Re: Tranny problems, help!

been too long for me to comment in all honesty.
But, I'm glad it was a quick and easy instead of a big visa bill kind of fix.
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Old 09-24-2007, 09:10 PM   #13
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Re: Tranny problems, help!

That looks right to me. It'll only go one way so you ought to be good to go.
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Being stupid ain't illegal.

We're Still Debt Free Except for the House!!!
www.daveramsey.com

70 GMC SWB Stepside project "Green Booger" soon to be 6.0l/4l80e
93 S-10 "Poppaw's Truck"
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Old 09-24-2007, 09:13 PM   #14
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Re: Tranny problems, help!

Congratulations! You have passed THM350 101 with flying colors. Now put the pan back on, fill it with fluid and have some fun.
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Old 09-24-2007, 09:23 PM   #15
Long Roof
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Re: Tranny problems, help!

Thanks a bunch guys! This is why I love this board.

Aaron
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The Good:
- 72 GMC Jimmy 4x4 - 307 cid / 350 th
- 70 Chevy Suburban 1/2T 2wd - 454 cid /400 th
- 96 Chevy Impala SS - mainly stock
- 98 Chevy Tahoe LT 4x4 - all stock
The Bad:
- 86 Chevy Suburban 1/2T 4x4 - winter beater
The Ugly:
- 72 Chevy Suburban 1/2T 2wd - parts truck
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