[Joe canyon]

I'll.say broke the shift cable with it stuck in neutral

 

[rune]

That would be a good guess as hell.... I dunno if it's not mechanical.

 

[Oo-v-oO]

I have never seen this mode of failure before. The smaller splined input shaft to the transmission stripped out, and if you look at the pictures the larger one shows signs of abnormal wear as well, though it had not failed yet.

Good splines:

Bad splines:

I didn't get a picture of it, but the mating splines in the torque converter seemed to be in good shape. This leads me to believe that these input shafts were softer than they should have been, and as such were defective parts from the factory that took 138,000 miles to fail. The replacement transmission has the same mileage as my truck does and as you can see from the pictures the splines are in perfect condition. Plus, like I mentioned, I have never seen a transmission fail this way. Bad heat treat or defective steel, I think.

I haven't got the truck all back together yet. The transmission is in but I still need to hook up cooler lines, tighten the torque converter bolts, install shift linkage, etc. then I have the transfer case and driveshafts to replace plus fill fluids but it should be done tomorrow night.
I don't have a garage and I have a dirt driveway which makes work like this tough. Add to that a very strong rainstorm that came through this afternoon and sent a miniature flash flood through my work area, and this job has really sucked so far.

So,
Used transmission: $500
Filter and input shaft seal: $40
2 quarts of Syncromesh: $18
12 quarts of Castrol Dexron VI and a deep 15mm socket: $101
3 days of crappy work so far with my son: Priceless.

 

[Sarge]

Did the previous owner seem like the type of person who would abuse the truck? If not, even though the truck is out of warranty, maybe a call to GM (or to the GM rep here on the site) and show them the input shaft. Might be something their engineers would be interested in looking at to see if they could determine a cause.

 

[FixxxerKH202]

Looks to me like it was a combination of the spline being machined out of tolerance and a bad heat treat. That's a really strange failure though, I have only heard of similar failures happening on really high horsepower/torque vehicles never on a stock vehicle.

 

[comdrop9073]

Looks to me like it was a combination of the spline being machined out of tolerance and a bad heat treat. That's a really strange failure though, I have only heard of similar failures happening on really high horsepower/torque vehicles never on a stock vehicle.

:yeahthat: Looks like the splines stripped right off.

 

[rune]

Damn........

 

[Oo-v-oO]

Did the previous owner seem like the type of person who would abuse the truck? If not, even though the truck is out of warranty, maybe a call to GM (or to the GM rep here on the site) and show them the input shaft. Might be something their engineers would be interested in looking at to see if they could determine a cause.

Absolutely not. He was very anal about the truck and went so far as to not sell it to someone he thought would take worse care of it than he thought I would. He has E-mailed me a couple of times just to say hi and see how the truck has been doing.

I'm new here and don't know the GM rep on-site - if someone could send him a link to this thread that would be cool.

 

[rune]

Yeah....I just have to say that's completely impressive. That's got to be a shaft that was not hardened. I seriously would not have guessed that. At least you are getting it swapped out.

 

[Oo-v-oO]

Well, my son and I wrapped up the truck tonight after work. The replacement transmission drives and shifts just like the one we pulled out, before it stopped working. No noises, slipping, or odd smells - I should be good to go.

I owe my boy a big favor for his help. I wouldn't have been able to do all that work by myself for sure.

I flushed out the trans cooler in the radiator with compressed air, drained all I could out of the converter, and I know the transmission itself was drained completely but I was only able to get about 8.5 quarts of the Dexron VI in when I refilled it. Looks like I have a few quarts left over for next time.

Thanks for all the ideas and suggestions.

 

[Oo-v-oO]

Did the previous owner seem like the type of person who would abuse the truck? If not, even though the truck is out of warranty, maybe a call to GM (or to the GM rep here on the site) and show them the input shaft. Might be something their engineers would be interested in looking at to see if they could determine a cause.

Well, I finally did find a GM rep on the site and PMed her a link to this thread. Never got a reply, so as I suspected it is probably too old for them to care about it. Oh, well.

Replacement transmission has been doing just fine (knock on wood!)

 

[Jeff_C]

Well, I finally did find a GM rep on the site and PMed her a link to this thread. Never got a reply, so as I suspected it is probably too old for them to care about it. Oh, well.

Replacement transmission has been doing just fine (knock on wood!)

Your truck may be too old warranty wise, but the failure you experienced is still vital info they may need.

My mother had a VW Passat that was out of warranty and had an engine problem that nobody had ever seen before. They had factory troubleshooters as well as the senior trainers from VW-USA come to work on the car and were writing the TB and a new section of the repair manual as they were working on the car. In the end they shipped the car back to the factory for a full teardown.

 

[terihill89]

I had the same problem. Just did the transmission swap yesterday. And still gears won't engage. Any ideas?

 

[cart7881]

I had the same problem. Just did the transmission swap yesterday. And still gears won't engage. Any ideas?

Welcome to the Nation. Looks like you missed this: https://www.355nation.net/forums/#intros-totm-355nation-news-and-information.3

Instead of digging up a 12 year old Thread, why don't you start your own.

Post a detailed description of your problem, including any related maintenance history, and what's been done to correct the issue. Include the make and model year of your truck and which engine you have and if it has a 2wd or a 4wd.

 

[BrighamSarrattpa]

2004 Colorado extended cab, 3.5, auto, 4x4, Z71 package, all stock, ~138K.

Driving to work this morning, doing about 35 mph and all of a sudden it felt like the transmission kicked into neutral and it started making a loud whirring noise. Now there is nothing in drive or reverse. Maybe it feels like there is a little bit of a bump when you put it in gear, but it won't move the truck at all. The whirring noise is tied to engine speed, but when you shut the truck off the engine stops but you can still hear the whir as whatever it is coasts to a stop a second or so after the engine.
Had to walk about 45 minutes home and of course it started raining so I got soaked.
jiofi.local.html tplinklogin
Going to go drag it home with my S-10, hopefully I don't get busted for expired plates. I see a transmission listed on car-part.com for $500 about an hour from home.

Any guesses as to what happened inside? I had absolutely no warning and I don't beat on the truck. I am quite sure the PO didn't, either.

This sucks.

Check and make sure you have tranny fluid in it.