eric.dally

There is a bushing in the tail shaft of the transfer case housing and once that wears then even a new seal will leak fluid. On mine when this happened I could jack up the back end so there was no load on the driveshaft and there was probably a little more than a 1/16" of radial movement of the yoke where it goes into the transfer case. For mine I had to rebuild the T-case for other issues so I replaced the bushing while I had it apart. I am not sure if you can replace the bushing without splitting the case, but if your somewhat mechanically inclined removing the T-case and splitting it apart can be done in an afternoon.

TTT

Correct me if I am wrong as I am not a suspension guru, but my understanding has been, at least for cars, that by increasing the stiffness of the rear swaybar it reduces understeer:confused: which would be very helpful for our trucks. I know my 03 has bad understeer and if I am on a spirited drive on a curvy road I can definitely feel it push sometimes. I was considering a rear sway to help with this.

Hey guys, I could really use some help. Does anybody have a broken transfer case sitting around that they would be willing to part out? I am in desperate need of some parts. The most critical part that I am struggling to find is the transfer case input gear its number 45 in the attached file. I also need a new mainshaft, number 43, if you have that as well. Transfer Case Explosion.pdf

Does anybody have any idea what could have caused this failure? It seems like there is no way for oil to get to that end of the mainshaft and it ended up causing the end to rust, but if that was the case I would think a lot more people would have this problem. I found all the parts I need except the input shaft so far, so if anybody has access to one they want to sell that would be awesome.

So about a week and a half ago I was driving home to the parents place for the holidays and was about 8 hours into my 13 hour trip when I had to slow down to about 40 for some traffic and then when I started to accelerate again all I heard was a horrible grinding noise (like gears slipping) and I lost all power in all gears. There I sat in the middle of the interstate in rush hour traffic in Minneapolis. So I got towed to an impound and borrowed my uncles car trailer and my dad's truck and hauled it back home. Once home I dropped the transfer case and took it apart and found that all of the splines between the input shaft and the mainshaft had sheared off allowing the input shaft to slip on the mainshaft. I have never heard of this happening before and looking at the splines that are failed they look like they are rusted. I am trying to figure out how they could have rusted, the transfer case fluid was still full and had been changed at about 50k miles. My truck is an 03 with approx. 65k miles on it, and I am not making hardly any more power than stock. Has anybody seen this happen before? Also for anybody that has swapped to the larger input shaft in order to use the 4l80e, does anybody still have their original transfer case input shaft and would they be willing to sell it for cheap?

My thought process is that the purpose of motor oil is to prevent excessive wear to engine parts, not to add horse power. And from my experiences I am confident that Mobil1 will protect my engine, as for the other brands I am not sure as I don't have experience with them. But I would be willing to sacrifice a couple HP to have that peice of mind that my engine is protected.

What kind of drop do you have in the front? Even at stock height it can be normal for the bump stops to just touch the lower control arm. It actually works as part of the suspension on a torsion bar setup like our trucks have. Having the bump stop adds progression to the suspension(i.e. makes it more stiff as it moves through its travel to prevent hard bottoming out). If you lowered the front using torsion keys or just cranking the keys down some guys have drilled holes in their bump stops to help soften them up. There is actually a post on here somewhere that illistrates how to do that, it should be under the "how to" section. I am not sure if anybody makes aftermarket stops for lowered trucks on the front, but that may be another option. If you lowered the front with spindles and did not change anything with the torsion keys I would suggest leaving the bump stops alone, should not have changed the geometry from the factory.

First thing you should check is how much clearance you have between your rear axle and the rubber bump stops. When I did my 4 inch drop in the back I cut two nubs off and removed the spacer plate and still only had less than an inch of clearance, and would bottom out even over small bumps. I ended up putting in a small c-notch and now it rides great.

Thanks for all the input guys. I decided to go with the airlift kit. I may need to fab up a lower mount depending on were the upper mounts to my frame with the c-notch, but I think it will work alright. My plan is to run two seperate fill lines, (one for each bag) with the schrader valves located behind the gas fill door. Does anybody have any watch outs for installing these bags, or any issues you have ran into? Thanks, Eric

Do you know who supplies the OEM gaskets? Are they Felpro gaskets?

I currently have a 4 inch drop on the rear of my truck with hangers and shackles, and I also have a DJM c-notch. Unloaded it rides great, but occasionally I need to either throw something in the box or tow a boat and it rides kind low then. Does anybody know which airbag kits would work with a 4 inch drop and a DJM c-notch? Would the Mcgaughys helper bag kit PN 33033 work, or what about PN 33024? Thanks in advance for the help.

I'm looking at rebuilding mine too, where can you buy a new chain for these units?

Ok, new question...Is there a difference between the NV149 and NP149? I can find parts for the NP149, but is that the same as ours? I was pretty sure we had a NV149??? If they are different does anybody know if the chain or rear case would work from the NP149, from the pictures I can find of the NP149 online it looks about the same as mine.

I may have been exageratting when I said an 1/8" I haven't actually measured it, but regardless there is a lot more radial play there than there should be and it needs to be fixed before it causes more issues. I'm one of those people that isn't going to wait around for it to break, I need to fix it as soon as I know something is wrong.

Thanks for the thought about getting it bored and sleeved, I had thought of that but wasn't sure if it would work with the magnesium housing. Also was there supposed to be a link or something at the end of your post, you said "try these guys" but I don't see anyone listed? Thanks,

Anybody??? Someone's gotta know a decent place to buy transfer case parts?

In the next month or so I am going to be pulling the transfer case off my truck to put my new torque convertor in and I've noticed the rear output shaft on the transfer case has started to get a little loose, maybe an 1/8 inch of play right now. Reading around I am assuming that the bore for the rear shaft bearing in the rear case half has more than likely become eggshaped and I will need a new rear case. Probably going to replace the chain while I am in there as well. Does anybody know of a place that sells reasonably priced transfer case parts for out cases? The only place I have found so far it was over $800 for the chain and case half. One thing though is they need to be new parts, I don't want to put used parts back on. Or if you have any ideas about how to fix this and prevent it from happening again please feel free to share them as well. And anybody that has done this before is there anything else that I should inspect or that needs to be replaced while it is apart? Oh yeah its an 03 with approx. 60,000 miles right now. Thanks, Eric

Personally I did not think it was that difficult and this was the first differential I had ever rebuilt. You can find a little info about this diff on line if you just do a google search for GM8.25 IFS rebuilds, it is the same as the 4x4 unit except on the passenger side we have a solid axle shaft from the carrier to the CV shaft and on the 4x4 they have an unlocking mechnism in the middle of the axle shaft. The carriers are the same Here a couple pointers from my experience and info I found: If your ring and pinion gear are still in good shape and you are going to reuse them it is unlikely that you will need to adjust the shims for the pinion depth. You still will want to check it though to make sure it has the correct depth by using the paint in the kit and painting a few of the ring gear teeth. To measure the backlash put the case halves together and tighten the bolts then take the measurement on the yoke on the pinion shaft, and then divide this measurement in half and that should be your backlash. From the research that I did this seemed to be the most accepted way of measuring backlash on these units. If your backlash or preload needs to be adjusted there are no shims in these diffs. You can see the adjustors in some of the pictures I attached above. If you screw the drivers side in and the passenger side out it will shift the carrier to the passenger side and vise versa for the other way. If you just tighten one but don't move the other this will increase your preload. If you have the special spanner wrench you may be able to adjust these without taking the case halves back apart but if you don't it will be much easier to move the adjustors if you take the case back apart so they are not loaded. My suggestion is that you check the backlash and preload before adjusting anything because mine was within spec so I didn't have to adjust them at all. If you do have to adjust them I suggest replacing the bendable locking tab as bending it multiple times will likely cause it to fatigue and break. Good luck if you try and rebuild it and let us know how it goes.

I've got a YFZ450 that I race XC and a little motocross with, racing is probably the most addicting thing I have ever done. If it wasn't for that thing I would def. have a lot more money to invest in truck parts.

I ordered them from completeoffroad.com, the entire kit was $130 and it came with everything that is needed for the rebuild. The item number on there site is Y GM8.25IFS-B.

The parts finally showed up and I had time to work on it but the camera was dead so I didn't get any more pics. Anyways it was pretty easy, I pressed the new beaerings on the carrier and painted a few of the teeth on the ring gear with the paint that came with the rebuild kit. I put the carrier in the case assembled the halves to checked the pattern on the teeth, and that looked good. So I checked the backlash and preload, and found both within spec. So I pulled it back apart cleaned everything again, put some silicone on the mating surfaces, torqued everything up, and put it back in the truck. Got to take it for a short ride but it sounds much quiter than it did before. Now I just need to replace the bearing on the output shaft of the t-case and the truck should be 100% again. I feel like there is always something that needs to be fixed. Oh well, at least its cold and crappy out side so I don't really have anything better to do.

Only a little more progress the last couple of days, I found out that it is pretty much impossible to remove carrier bearing with a cheap @$$ two finger bearing puller and managed to break one of the fingers off, oh well. Decided to get out the dremel and cut into the races being very careful not to cut too deep. Then hit it with a chisel and they split right down the side. Now I'm just waiting for the new bearings and I should be ready for reassembly. I haven't really had any responses to the questions I've had in this post but I am mostly doing it because I read a lot about people having different noise issues with the front diff but there isn't much information about actually fixing the diff. I like to think I have pretty good mechanical ability but I had never rebuilt a diff before so this is a learning experience for me and hopefully someday if someone else gets fed up with listening to their front end growl some of this post is usefull for them too.

The fluid actually didn't look as bad as I expected, it was a pretty dark but only had a small hint of metalic color to it. There were also some fine shavings on the magnet of the drian plug too. Compared to what other I have read that other people posted I expected much worse especially with how bad the sound was when I would turn. Looking at the ring and pinion gears I think I caught it in time it didn't damage the gear set.

I got it almost all the way torn apart yesterday, it turns out if you use a slide hammer the axles pop out quite easily. Once the axles were out I removed the passenger side axle housing and removed all of the bolts to split the case. Splitting the case proved to be the most difficult step so far as the dowel pins had corroded and it took quite a bit of force and a little help from heating the case with the torch to get them free. Once split the carrier is loose as the two case halves are what actually hold it in place. I removed the diff and started inspecting the bearings and races, I found that the passenger side bearing and race were badly pitted but the driver side was in pretty good shape. I'm assuming the passenger side bearing is under more stress when driving as this is the ring gear side. Next step will be to remove the pinion and inspect those bearings. I didn't have the correct socket so that will have to wait until tonight. Then I will just be waiting on part to show up. The kit I ordered comes with both carrier bearings and races, both pinion bearings and races, the crush sleeve, yoke nut, and stuff to mark the ring gear to see the pattern. If anybody has any input this teardown, can think of anything else I will need please feel free to comment. Here is a link to the pic I have taken so far: Front diff disassembly Hopefully the link works, and I will continue to update it as the project continues.