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Old 05-06-2002, 05:59 PM   #1
Longhorn
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Post Posi experts please?????????

Grandson's 71 with posi pops when taking off going around corners. Seems to be ok on straight pull. Truck has 250K on it. I purchased GM additive but not add it yet. What else can I expect? Are the clutchs for these still available if I have to tear her down? Thanks for your help.

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Bill

Rapid City, SD

67 short stepside, in weeds 6Cyl
69 Longhorn CST 396 nice original


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Old 05-06-2002, 06:07 PM   #2
shortbed70
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I'm not an expert but I do know that most posis make some sort of noise weather it be a poping or whinning clicking so forth. I cont know how to rebuild these fine units but I wish you good luck.

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1970 shortbed(project)
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Old 05-06-2002, 06:16 PM   #3
texnician01
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I believe that the clutches are still available, they were made by Eaton. I'm not an expert by any means though.

Nathan

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1969 C-10 292 I-6 4 spd in the middle of a restoration. going to get a 327 and 3.07 gears but keeping all of the original parts so I can put it back to original later on down the road.
55 chevy 4 door 150
47 Willys CJ-2A

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Old 05-06-2002, 06:24 PM   #4
COBALT
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Randy's Ring & Pinion
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Old 05-06-2002, 06:24 PM   #5
Mike C
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Sounds like the lubricant is contaminated. Drain and refill with appropriate rear oil and the GM positrac friction modifier additive. Might be a good time for a pinion seal and axle seals as well as the new cover gasket. It is possible to get rebuild parts. I went through my Eaton posi about 12 years ago. Clutches were about $50 a set back then and springs about $10 for 4.

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70 GMC 3/4 ton Sierra Grande 402/TH400
72 Jimmy 4WD 4spd 4" & 35's
64 Corvette Coupe
68 Camaro 'vert TPI & TH700
69 Z/28 355 12.6's @110
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Old 05-07-2002, 01:11 PM   #6
JW
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Used to race Corvettes,16 years, have a Posi in my 72. The "POP" is the Posi plates releasing. Problem is either worn Posi plates, posi springs or both. To remove a posi is not to bad, to install can be dangerous. The posi pack, plates and springs, have to be compressed for installation. We use two C clamps, then tap the pack in. If not done right the pack will come apart. I installed a rear end cooler on my truck, adds to the life of the posi.

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72 Cheyenne Super, Fleetside, Shortbed,
Original Owner, Special Ordered
350ci/340hp, Auto Trans, 3:70 Posi, Tow Package
Northern Calif


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Old 05-07-2002, 02:42 PM   #7
HuggerCST
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I had one years ago in a '72 that started popping like that. I changed the fluid, put in the GM additive, and the popping stopped. Never had another problem with it.
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