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2006 chevy trailblazer_ls
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Discussion Starter #1 (Edited)
So it seems that every month so far this year has plagued me with some kind of financial "incident".

Yesterday I had taken some stuff over to a good friend of mine's house. I had to 4wd backwards into his yard to get over a curb. Later on I left his house and noticed a noise coming from the transfer case. I just had it serviced no more than three weeks ago. I took it back to the shop that I know and trust (and originally did the TC service). The sound has stumped them.

When in 4HI, it makes this rubbing noise noise, as soon as you pull it into Auto or 2wd, the noise immediately goes away. All four wheels spin when 4HI is engaged. But it makes this rubbing noise. Not a "gravel" sound or metal-on-metal, but more like a rubbing noise that gets louder when I speed up. It sounds like you drove through tall grass and something is caught in the wheel kind of rubbing sound that gets louder as you speed up.

I have no noticeable decrease in performance and the autoshop has determined the noise is coming from the transfer case and not the passenger side wheel as I had originally thought. I wasn't getting a good vibe from my mechanic that he knew the TC very well like I've heard Roadie does, but my mech's suspicion is that the shift fork has nylon on the tips of it. This appears to be rubbing on the thing it's suppose to connect to when engaging 4wd.

Sorry my terminology is limited but I'm getting much better than I used to be a year ago. I just can't remember the object that the shift fork connects with to engage the front axle. It's also possible that the oil pump that's in there may be clogged with nylon/metal shrapnel.

Anywho, they want to charge me 300$ to just LOOK at it and tell me what's busted and then to fix it for additional money. Again, I was getting a strong vibe and the "reading between the lines" that they don't work on too many TC, let alone TVs to warrent any confidence in their service.

After all that, how hard would it be for me to take the transfer case out, crack it open myself and look to see if anything is amiss? Rate 1 to 10? 10 being "difficult for a trained mech" and 1 being "as easy as pumping gas" :)

Like anyone else, if I put my mind to it I can do anything, but if this is going to be well out of my element, possibly do more harm than good, by all means, please let me know. Thanks for all your help!

Edit: I should also note, the TC threw NO codes at all. The light for the transfer case switched gracefully between 2wd, to AutoWD to 4HI and back again without hesitation or excess/scary noises while doing so.
 

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2004 gmc
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Could be the clutch stack. Lots of things that can break - early ones had a too-weak fork. For $200-300 from Ebay or the junkyards, you can get a used one. Don't even TRY to rebuild the old one, is my opinion. Crack it open for a failure analysis and so we can learn stuff, but slap in a different one.

The TC cannot throw any codes. Only the TCCM can, and it doesn't know anything about the internals of the TC. Just whether or not the encoder motor succeeds in moving to the commanded angle.
 

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2006 chevy trailblazer_ls
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Discussion Starter #4
Don't try to rebuild the TC? Or don't try to rebuild the clutch stack?
I'm taking my truck tomorrow to a well known transmission guy a few miles down. See if he can give me some more insight into what he thinks.

I might try to drop the TC myself and crack it open myself to find any defects and report back. Do you think it will hurt the truck to continue to drive it in 2wd the whole time?
 

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Don't try to rebuild the TC? Or don't try to rebuild the clutch stack?
With the low junkyard prices out there, I wouldn't even crack the case except for curiosity. With axles going for $400, I wouldn't even pay a gear shop to change ring gears and set them up, let alone add a G80 to a vehicle that didn't have one to begin with. I upgraded to a stronger EXT rear axle basically for $400.
Do you think it will hurt the truck to continue to drive it in 2wd the whole time?
It wouldn't hurt anything, but without the TC there, the driveshaft won't reach the tranny.

 

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Discussion Starter #7
I want a pic of the curb you needed 4x4 for...:excited:
LOL! I can explain that honest!
I had my rear wheels in my friend's yard/grass, and as I tried to pull my front, I was pulling up his yard a little too. Then I figured, I still have two wheels on asphalt so why not 4wd? :undecided:bonk::hopeless
 

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Discussion Starter #8 (Edited)
Last night, I was reversing out of a longer driveway, I could hear the sound again, but I was in 2wd this time! :confused:
I took it to a local transmission shop that has some good "street cred".
He is going to look at it for me for FREE (that's 0.00$ vs the 300$ from the local mech) and update me tonight on what he thinks is wrong. Plus, if he can get the parts for me, he'll also do the 'Vette servo AND the .490 boost valve :thumbsup:


Dirtychevymama:
This was what I was trying to reverse over in 4wd, honest!

:dielaugh:
 

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Discussion Starter #9
Update: I just heard back from the transmission people. Heh, it's almost comical.

He said that it is an issue with the transfer case (a confirmation I couldn't really get from the local mech). That it is dropping out of 4wd when there is a load on it. He said he applied some brakes with the wheels moving and can tell that the 4wd is dropping out.

Something I found interesting, probably very interesting. He stated that the transfer case appears to have been painted in aluminum, before being mounted to the truck. The bolts holding it on are not painted however. He stated that it does look like the TC has been worked on in the past.

He wants 300$ just to take it apart and tell me what's wrong (can't seem to get away from that number!), and at least 900$ to fix whatever it is and get it going again, possibly up to 1300$!

I know a couple of junk yards I could probably check to see what they have in stock. I think it's going to take a while before I run into a newer 4wd TB that still has a transfer case in it.

It looks like I could pull my own transfer case out of a junk truck for 90$ which is a bargain compared to spending 1300$ to drop an 80 pound hunk of metal. I've got some assurance from the trans-man that the truck is very drivable in 2wd and won't hurt anything so I still have a daily driver. :crazy:

Stupid curb :hissy::laugh:
 

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Discussion Starter #10 (Edited)
Quick update, I found a place that sells junkyard parts for pretty decent prices. They just moved in less than a couple miles from my place called LKQ.

I got a transfer case with 31k miles on it for 275$ and it comes with a 6mo warranty! I thought it was a decent deal and I'll definitely be going back for more parts if ever need be.

I plan on taking it to my parents for the weekend and see how long/quick it takes to swap out the TC.

I should be able to find me 4 jackstands without having to go out and buy them. Is there anything that I should look out for (other than the 80 pound TC falling on my chest) or tips? I've never done anything this extensive to a car before. I've got my Haynes book and my wits, with the right tools I think it will work out.

What has bugged me though is why don't these shops recommend that I replace the TC or offer to do it for me? they all wanted to rebuild the old one and not go out and buy the 300$ tc and throw it up in there for me? :no:

If I remember to do so, I'll post some pics of the switch, hopefully it will be useful to someone else on here
 

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It's really easy to swap the transfer case just make sure you get the gasket or oring can't remeber what it is, that goes between the transfer case and the transfer case adapter and 2 quarts of the transfer case fluid from the dealer and make sure you get all the connectors and hoses unhooked before you completely drop it down it's a bugger to lay under there with a transfer case on your chest and unplug things. Make sure you unbolt the tranfer case from the adapter and not the back of the transmission because the adapter serves as the transmission mount. to get the front drive shaft loose i had to use a piece of pipe and a hammer to knock it loose from the snap ring on the transfer case. also excpect to loose a little bit of transmission fluid if you make sure the back of the truck is higher that should help to keep it for loosing to much . If you got any other questions i'll sure try to answer them i had my t-case out twice in one day so i got the hang of it.

Hope that makes sense i sometimes confuse myself when i explain things.
 

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Discussion Starter #13 (Edited)
I'm having some trouble removing the front driveshaft from the transfer case
i'm afraid to hit it hard that i break a snapring or something. I'm trying to pull on it like how the rear came off (it just slid out), but the front seems locked. I don't want to pull any harder and tear the seal thats around the front drive shaft. Or do I remove the ring thats around the drive shaft and the rubber gasket that's covering it?

edit: also it looks like on the replacement TC, the rear driveshaft seal is torn....is that important? I was going to unbolt the good rear driveshaft section of the TC and put it on the replacement TC, also it looks like i have to transfer the motor from my old one to the replacement as it looks like they just cut through the cables instead of just unsnapping it from the scrap truck
 

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The rear slip joint just slips off the splines in the transfer case. The front one, for some odd reason, has a circlip like the ends of the CV shafts. It snaps out, but the shop manual is silent on any hints of how to do it easier. They DO warn to not pound on the ujoint yoke to separate the shaft from the TC.
 

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I'll try to answer your questions as good as i can so here we go There is a snap ring on the shaft that comes out of the transfer case that holds the shaft to the TC don't pull on that shaft try to pry it or hit it from the other side. and replace that seal save yourself some headaches down the road
 

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I think i used a rubber mallet to pop it off. I can't remeber i think the guy helping me did that part.
 

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Discussion Starter #17 (Edited)
UPDATE:
i got the front driveshaft off and am in the process of removing the transmission mount from the crossbar. I don't have a snap ring readily available to replace on the front of the TC for the driveshaft. Are those just a common snap ring? I will have to head to the auto store for some grease for the splines. Any recommendations? I might pick up a new snap ring if you can give me an idea of what to ask for (just your basic clip ring?)
now i'm stuck on removing the transmission mount. I don't want to raise the transmission up too much and risk damaging something. What's the maximum height that i can comfortably raise the transmission and not risk breaking something expensive?
The bolts from the transmission mount are preventing me from pulling the transmission mount off the crossmember. So right now I'm right before being able to get to the transfer case adapter nuts holding the TC on.


Thanks for all your help
 

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Discussion Starter #19 (Edited)
Are you doing this without the benefit of even a Haynes manual?
I'm doing this at the mercy of the Haynes book yes.
It's telling me to unbolt the transmission mount from the crossmember (done)
support the transmission with a jack (done).
Then it says in chapter 7B-2 section 7 step 8 to remove any transmission to transfer case support braces (done? i dont know of any other brace other than the transmission mount to the crossmember nuts, and the transmission mount to transfer case adapter nuts)
Raise the transmission enough to remove the transmission mount (see chapter 7a) then support the transmission on a jack (done)

On 7a, i'm on section 7 step 5 under "replacement", raise transmission slightly with a jack and remove the mount (stuck)
I have the transmission raised a good 2 inches, but the bolts from the transmission mount going into the crossmember are preventing me from lifting the mount and removing it. Is it safe to jack up the transmission an inch or two higher without damaging anything?

thanks in advance :thx

edit: i'm moving forward without removing the transmission mount. through due diligence, i will unratched the nuts slowly but surely from the TC adapt from the TC. I removed the bottom one first with the transmission raised about ~2 inches, then i will lower back onto the transmission mount and remove the top nuts from the TC adapt. the last two (on each side of the bottom nut) are easy and will come out with or without transmission lowered/raised
many pics to come afterwards
 

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Your making a lot of extra work for yourself did you read what I wrote the first time
 
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