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Discussion Starter #1
Good afternoon,
I have an odd issue that is driving me crazy. My 1993 K3500 is stuck in low range. This year/model does not have the selector switch on the dash it is the lever that is on the transmission hump. For the life of me I cannot get the truck out of low range. Regardless of the position of the lever, 4L, N, 2H, 4H the transfer case refuses to shift out of low. Even in neutral the case is in low. I have driven it (on gravel) in all 4 positions for over a mile, driven in reverse for several hundred yards and still nothing seems to work. I can get under the truck and move the linkage to all 4 positions without a problem so the issue seems to be internal. Perhaps the range fork is somehow not disengaging low? I do not want to drop the case but I think that is where I am at right now. Anybody ever had this issue? Any ideas? There is no grinding or "banging" whatsoever when the lever is moved either via in the cab or under the truck. The axle disconnect is working just fine. I placed the truck on jackstands and put the transmission in gear in both 2H and neutral and the front wheels do not turn. In gear with the lever in 4H and 4L the front tires turn.

Engine: 454
Trans: 4L80E
Transfer Case: BW 4401
Miles: ~110K

I am at a complete loss and about ready to simply drop the case and go through it. I will need the truck to haul some tractors in the next few weeks so I need it out of low or it will be a very long drive.

Any help or ideas will be greatly appreciated, perhaps I am overlooking something simple.
 

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Discussion Starter #2
Well I gave up and pulled the case out, kinda rough without a transmission jack, but no real issues pulling it. I split the case last night and found a broken range fork (as I suspected). Unfortunately the clutch coil housing was grenaded in the process (I am assuming the fork failed first). A quick inspection did not reveal any gear or other damage. I will disassemble the rest of the case and clean/inspect everything and get the parts ordered. At least I know pulling the case was not in vain. Fork broke right at a point that is a stress riser. Either the part was clearanced there for some reason (will look at that tonight) or it's a poor design. Fork is more or less die cast pot metal, not a real impressive piece. Really not sure what caused the issue. I could not find any remnants of any fork pads so I wonder it they were missing from new (??). Truck had 3 miles on it when we picked it up in '93 and only my dad, son, and daughter, and me have ever driven it. It has spent very little time in 4WD.
Will try and post up some pics later.
 
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Discussion Starter #3
Whelp, the truck will likely be down for some time. The clutch coil housing seems to be a unicorn. I have tried several parts suppliers in the US with no luck. I have a supplier in Canada doing a search for me now. I don't want to have to buy a used case for one part but it may come to that.
Case is cleaned up and the parts that are available are on order. I need to replace a couple of marginal bearings but I should be able to find those local. I want US made bearings so I really want to see before I buy. I have had poor luck with Chinese bearings in tractors. I learned my lesson with those.
 
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I have heard of these forks getting broken.
Did someone magilla-gorilla on it? Sounds like this truck has had a good life with original owner.
Lookin' forward to some pictures.
 

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Discussion Starter #5
I have heard of these forks getting broken.
Did someone magilla-gorilla on it? Sounds like this truck has had a good life with original owner.
Lookin' forward to some pictures.
I have no idea why the fork let go. I dropped it into 4L to back a trailer up in a soft pasture. Just wanted a bit more control. After that I could never get it back out of 4L. In all the shrapnel I was never able to find the pads for the range fork so perhaps they were never installed from new??? I don't remember a time when it was forced into low range. It has always been a bit cranky to get into low and oftentimes took a bit of coaxing by switching from N back to D or R to get things lined up but I never had to hammer on it. Where the fork broke there was a bit of porosity in the casting so maybe that was cause. I likely will never know. Other than a water pump 15-20 years ago this is really the first real repair I have had to do on the truck in 27 years.
 

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Discussion Starter #6
Ok, finally took the time to upload some images of the mechanical destruction. Below is the broken shift fork, grenaded clutch coil housing, and damaged oil pump bracket.

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166859
 

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Discussion Starter #7
So I managed to break the two parts that are not longer available; the oil pump bracket and the clutch coil housing. Fortunately after some searching I managed to locate a used housing in Florida and the oil pump bracket in Calgary. I now have everything on order and am now just waiting for parts. The clutch coil housing should be here on Tuesday and I will take it into work and Magnaflux it just to make sure it does not have any cracks. I am also going the local bearing supply house and get the bearings I need. After tearing the case completely apart the best course is to just replace the bearings since I don't want to be in there again. In the meantime I blocked the sealing surfaces on the case with 400 wet/dry paper and used WD40 for grinding fluid. I also honed all the thrust washers, snap and lock rings on flat plate using the same method I used on the case.
Built a couple of tools for pressing the tone wheel on the mainshaft and for pressing in the seals.
 

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This is one of the most interesting things I've read all day. Good work on grenading and good work on fixing. Keep on keeping on🤘🤘🤘
 

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Clutch coil housing arrived so magnafluxed it and all is well. I got it from Cobra Transmission in Sebring FL. The guy I worked with was great. He tore down 3 t-cases in order to find the best one for me. The hardest part to find was the first one to arrive. I hope to see the balance of the parts by next week. I ordered Timken bearings from a local supply house and those are coming from TN sometime this week. I could have used something off the shelf but I really wanted Timken as I have always had good luck with their stuff. I will take a couple pics of the press tools I made for the reassembly and post them up. The tone wheel is pressed on the mainshaft and you need a tool that will fit over the splines and press on the wheel. The length of the shaft is about 7" so it is a long reach. Also one of the seals is a bit of reach into the housing so I made a tool that will make that easier to press in.
Couple more shots of the destruction. Fortunately the damage looks worse than it is. The truck was not driven far so the shrapnel did damage anything else.
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