1997 GMC Suburban Transfer case

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BowtieBrody

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Need some urgent help on figuring out if it's just my transfer case that's dickered,


Push-button 4x4, which I think is the NP263? Someone correct me if I'm wrong;

I was leaving for work this morning and felt a sudden jerk; I thought at first my trans lost reverse as all it would do in reverse was rev. But once someone gave it a shove to roll it backwards it popped and I could back up.

Got home, looked underneath and saw fluid coming out of the tail-housing on the case,
went to drive to the transmission shop, popped, clanked and jumped in reverse; put it in drive and it was normal for a second until I started rolling a longer distance as it started making a grinding noise.

Is it my t-case that's screwed? Or is there something more I'll need to dump money on?
 

aaronb

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What buttons do you have on the dash? 4hi, 4lo, and 2hi would be the 243.
If it also has the Auto 4wd it will be the 246. There is a tag on the back of the case by the fill the plug that will tell you What case it is.
Something to check, pull the driveshaft out of the rear out put and grab a hold of the output shaft. If you can move it in and out pretty far or easy to move in and out. you more than likely broke the snap ring that holds the output shaft against the pump. The snap rings are notorious for breaking.
 
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BowtieBrody

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What buttons do you have on the dash? 4hi, 4lo, and 2hi would be the 243.
If it also has the Auto 4wd it will be the 263. There is a tag on the back of the case by the fill the plug that will tell you What case it is.
Something to check, pull the driveshaft out of the rear out put and grab a hold of the output shaft. If you can move it in and out pretty far or easy to move in and out. you more than likely broke the snap ring that holds the output shaft against the pump. The snap rings are notorious for breaking.

Thank you for the correction on the T-case,
Would the snap ring failure cause the truck to buck and grind in reverse, and grind going forward?
 

aaronb

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When mine broke, I had severe grinding and a vibration in reverse and going forward. I'll try and find the snap ring part number. I got the replacement from a place called cobra Transmission on eBay. It was around $15 for 3 snap rings. None of the local parts stores had one the correct thickness or size needed.
 

BowtieBrody

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When mine broke, I had severe grinding and a vibration in reverse and going forward. I'll try and find the snap ring part number. I got the replacement from a place called cobra Transmission on eBay. It was around $15 for 3 snap rings. None of the local parts stores had one the correct thickness or size needed.

I'll definitely try and see if that's the what the problem is, how involved is the replacement process?
 

racnredneck

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most defiantly will. can fix for @ 25.00 but all the possible metal is in the case and can plug up the pump filter screen.. best to remove case disassemble and clean inspect and reassemble, but if cant do that just the ring will do for now.
 

BowtieBrody

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Hopefully it's just the snap rings and not the internals of the transfer case or the transmission; called a mechanic and he said it could be the ****** sun-shell gear or whatever it is in the 4L60E that is prone to failure
 

aaronb

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To get to the snap ring, remove the driveshaft. Remove the 4 bolts from the tailshaft and remove it. You'll either see the snap ring in pieces or it will still be in the groove on the output shaft.
The new snap rings I got have the little ears on it so snap ring pliers makes installing the new one easy, the old one doesn't have the ears and can be a ***** to install or remove.
 

BowtieBrody

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