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My transmission is slipping...

Discussion in 'Chevy Suburban Forum (GMC Yukon XL)' started by janikphoto, Dec 24, 2012.

  1. janikphoto

    janikphoto New Member

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    1999 'burb with 200k miles and the trans feels like it's slipping. Not a good sign, I assume?!?
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  2. Conlan Rose

    Conlan Rose Super Moderator

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    Ok, we need a little more info like your driving style, how often you change fluids, the transmission, if you have a cooling system and other info like that. Slipping usually is never a good thing, but the extent of how bad it is slipping determines how we fix it. I've only felt my tranny slip once or twice and doing a simple transmission flush and replacing the filter did the trick.
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  3. janikphoto

    janikphoto New Member

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    I did a fluid and filter change 10k miles ago. The fluid still looks clean, doesn't smell burned. The truck is a 99 k1500 4x4 burb with the 5.7L in it. I spent the last month driving it pretty hard, since I had that bucking problem between 1 and 2k rpm... it might've hurt the trans. Now, it feels like a slipping clutch on a manual trans vehicle when I press the gas from a stop, then seems to "grab" firm around 2k rpm. I'm assuming that's because the torque converter is locking at that point?
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  4. Conlan Rose

    Conlan Rose Super Moderator

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    The bucking problem may have put some strain on the tranny. Personally I'm kinda tranny stupid I know what may cause problems and sorta why, but don't have much on fixing them... Do you have a tranny cooler? Also do u use the truck for towing? Since you live in Dallas the tranny has to reach high temps, the number one killer for transmissions is heat.
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  5. janikphoto

    janikphoto New Member

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    No added coolers... just what the factory would've included. The heat hasn't been bad lately, so I doubt that's what did it in. I think i was the hard driving during my problem. I had to keep the rpm's above 2k for it to drive OK, so I'd manually shift it. I'd have to manually keep it in 2nd or 3rd, with consistent 3-4k rpms for extended time... but, the fluid still looks great inside. Oh well... at 200k miles, I'm sure a new trans was somewhere in its future!
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  6. Conlan Rose

    Conlan Rose Super Moderator

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    Yah the tranny isn't usually dealing with those rpms during normal driving. I say if you replace the tranny you should get a 4L65e which is a bit stronger than the 4L60e but uses the same exact connectors, pan, fittings and has the same dimensions.
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