broken t-case

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67Coug
Posts: 2
Joined: Mon Jan 12, 2015 10:32 pm
Location: Flagstaff, AZ

broken t-case

Postby 67Coug » Mon Jan 12, 2015 10:53 pm

Hi! I'm new here-have owned early Broncos since 1974 but just recently bought an '87 Bronco ll for a grand daughter. Her dad and I have gone through it and thought it was ready for a road trip. Last thing was new tires last week. She drove up to Flagstaff form Phoenix and said it made a noise she had never heard before as she turned down my street. She couldn't describe it. I found the power steering low and thought that was it. Next day she and I headed to Colorado. About 300 miles down the road it made two loud 'bangs'. We stopped but noticed nothing wrong so kept going. A couple hundred miles later I crawled under and found ATF all over the frame, then noticed a crack in the t-case. from just above the fill plug and curving around and up to the output seal bore. I got a couple hose clamps and some JB Weld and "McGuyvered" it. Made it OK to Castle Rock to her friend's house. I flew home and went to "U-Pick-It" today.
There it hit me: the locking hubs come right off when the wheels are removed. My question: Has anyone had a tire jockey knock a hub off and mess it up so that it suddenly locked going down the highway? That's what I think happened but am wondering if this is a possibility.
Thanks for your help! Allan

Lance Skene
Posts: 131
Joined: Fri Dec 27, 2013 8:06 am
Location: Calgary Alberta

Re: broken t-case

Postby Lance Skene » Tue Jan 13, 2015 9:56 am

Is this all manual or electric shift and auto hubs?
Atf fluid is coming out of the t case?
"T" = transfer or transmission?

The hubs could be damaged if they were not properly lined up when the wheel was torqued but I dont see how they could damage the transfer or transmission case unless your trying to shift into 4x4 on the fly while the hub is locked.
'80 Bronco 351M
'85 BII 2.8/Duraspark
'89 F150 302 Supercab

67Coug
Posts: 2
Joined: Mon Jan 12, 2015 10:32 pm
Location: Flagstaff, AZ

Re: broken t-case

Postby 67Coug » Tue Jan 13, 2015 10:16 am

Thanks for your reply. It is electric shift and auto hubs. The transfer case is cracked at the rear output seal area and leaking fluid. I am wondering if it is possible for the tire shop to have bumped the auto hubs loose when doing the tires, causing the hubs to suddenly engage at 75 MPH which would put a shock load on the transfer case. Has anybody had this happen?
Thanks.

Lance Skene
Posts: 131
Joined: Fri Dec 27, 2013 8:06 am
Location: Calgary Alberta

Re: broken t-case

Postby Lance Skene » Tue Jan 13, 2015 11:41 am

Doesnt sound very likely, the shock would have to tranfer from the hub, thru the axle shaft, the front diff, and the front drive shaft before reaching the transfer case. Unless both hubs were to lock at the same time any shock would be absorbed by the front diff. Have you removed the hubs to look for damage?

I would guess its more likely that the crack was there before you bought the truck and just opened up more now, possibly caused by a bad u joint or maybe somebody high sided the truck at some point. Although having electric shift there is also a possibility that a short in the system caused it to shift into 4x4 on the fly... but Ive never heard of it happening and Ive been around B2 forums for about 8 yrs.

Sry not much help :(
'80 Bronco 351M
'85 BII 2.8/Duraspark
'89 F150 302 Supercab

User avatar
tekatlarge
Posts: 951
Joined: Tue Jan 17, 2006 8:54 am
Location: Kent, Worshington

Re: broken t-case

Postby tekatlarge » Wed Jan 14, 2015 8:21 am

I think Lance was right on with his possible explanation. It sounds like it may have been a drive shaft problem to begin with. Like he said maybe someone high centered the rig on the drive-shaft. It could also have been a bad U joint at some time previous in life.

The front auto Hubs are notorious for NOT engaging. I also don't think there was any internal failure to the transfer case as They are sturdy as hell and instead of gears turning together it uses a link type chain to couple internally.

Oh yeah the ATF from the transfer case is normal the transfer case is normally filled with ATF.
The Tek @ Large
Kent,Worshington
I was borne under a rock. So what's your excuse?

Lance Skene
Posts: 131
Joined: Fri Dec 27, 2013 8:06 am
Location: Calgary Alberta

Re: broken t-case

Postby Lance Skene » Wed Jan 14, 2015 10:39 am

Even if one hub was locked it wouldnt turn the front diff so I doubt it caused of the problem here... and these t cases are tough... takes alot to break them.
'80 Bronco 351M
'85 BII 2.8/Duraspark
'89 F150 302 Supercab


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