99 GMC tranny?
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Topic: 99 GMC tranny?
Posted By: Tracy Martin TN
Subject: 99 GMC tranny?
Date Posted: 13 Sep 2020 at 6:31pm
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I think my truck has had a major problem arise. Today it popped and while it is moving tranny sounds like Halloween in Hell! Raised back tires of ground, can spin them with no major noise. Put truck in gear and tranny sounds like broken or missing teeth on gears. What is most likely culprit? Any help appreciated. Tracy ------------- No greater gift than healthy grandkids! |
Replies:
Posted By: Walker
Date Posted: 13 Sep 2020 at 7:45pm
| Somebody stuck a tire iron through somebody elses u joint where my daughter worked years ago. Her description sounded a lot like yours. |
Posted By: Tracy Martin TN
Date Posted: 13 Sep 2020 at 8:03pm
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Pretty sure it is the sun gears. Hope it isn't a too costly fix. ------------- No greater gift than healthy grandkids! |
Posted By: Hubert (Ga)engine7
Date Posted: 13 Sep 2020 at 8:08pm
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You may come out ahead putting a rebuilt unit in instead of trying to fix the old one. Depends on how many miles you have on it and how many more you hope to get out of it. ------------- Just an old country boy saved by the grace of God. |
Posted By: Tracy Martin TN
Date Posted: 13 Sep 2020 at 9:11pm
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Hubert, around 250,000 on it. Would like to get several more years out of her if possible. Tracy ------------- No greater gift than healthy grandkids! |
Posted By: shameless dude
Date Posted: 13 Sep 2020 at 11:16pm
| manual or auto? |
Posted By: Tracy Martin TN
Date Posted: 14 Sep 2020 at 8:46am
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auto. ------------- No greater gift than healthy grandkids! |
Posted By: Boss Man
Date Posted: 14 Sep 2020 at 10:12am
| Sounds like a bad planetary. I would look for a used low mile replacement. |
Posted By: Tracy Martin TN
Date Posted: 14 Sep 2020 at 1:32pm
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None to be found. I guess it is getting rebuilt. Tracy ------------- No greater gift than healthy grandkids! |
Posted By: Thad in AR.
Date Posted: 14 Sep 2020 at 1:55pm
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Tracy for what it’s worth I drive a 99 GMC also. Had to rebuild the transmission at around the same miles. That’s been the only major expense on this truck. It’s at 400000 miles now |
Posted By: Coke-in-MN
Date Posted: 14 Sep 2020 at 3:05pm
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2 wheel or 4 wheel and what transmission ? I was looking for a transfer case for my 2000 GMC and came across more transmissions both 4L60 and 4L80 but each has a different output shaft . As I have a 4L80 finding the right transfer case was a hunt , then finding the right electronic controller unit was another problem - ended up replacing clutches and bearings in mine - cheaper than any rebuild I could find and was a couple hours work once unit was out of vehicle . ------------- Life lesson: If you’re being chased by a lion, you’re on a horse, to the left of you is a giraffe and on the right is a unicorn, what do you do? You stop drinking and get off the carousel. |
Posted By: Tracy Martin TN
Date Posted: 14 Sep 2020 at 10:04pm
4 wheel drive 4l60. Hope they can get started later part of this week. Been a good truck. Less problems with it than any of the newer ones my friends have. Too much bull on the newer stuff. Tracy------------- No greater gift than healthy grandkids! |
Posted By: shameless dude
Date Posted: 15 Sep 2020 at 1:54am
| that's why i've kept my '97 and '98 too Tracy, plus my back don't hurt driving them. my old lady's....oooops....i mean my loving wifes new burb has leather seats and i can't drive it as long as my pickups with the cloth seats. |
Posted By: Dirt Farmer
Date Posted: 15 Sep 2020 at 3:25am
| Greetings everyone, enjoyed this site for many years and can’t let a Chevy truck person down. Sounds like the noise maybe the pesky snap ring on the tail shaft of the transfer case. Jack up and support the rear end to keep fluid from leaking out, remove rear drive shaft, then take off tail shaft housing to reveal a broken snap ring that goes into a groove on shaft to keep the shaft engaged in the sprocket. Learned this the hard way after replacing the chain in the case only to have the noise continue. Replaced the snap ring and problem solved. Hope this helps and saves you time and money. If the truck is still moving then the transmission is doing it’s job. |