Drivetrain failure on the interstate

[Aphix]

I was getting on to the interstate when I heard a little gear whine from my drivetrain, I thought it was kind of peculiar but not too terribly out of the ordinary and I had an appointment to make, so I kept going. About ten miles down the interstate I feel this lurch from my car, it only happened once, about a mile later I begin to have major drivetrain issues where the engine is acting sporadically and I can feel the front and rear wheels are out of sync. As I coast to a stop the car gets a lurching feeling even though its in neutral. The engine is running fine.

I jump out and look underneath it and I see oil being burnt off the transfer case, but I cant tell if it is directly from the t case or not. I get back in and am able to drive it a few yards farther off the road while the front and rear wheels clearly werent agreeing.

Later I come back with a trailer and am able to put it into reverse and first gear and drive it up onto the trailer without much fuss from the car. I got it home and drove it around my yard and got it into 3rd gear fine, but heard some binding. So I jacked it up and started playing with the wheels. I found that the two front wheels would spin free from eachother in neutral and could hear what sounded like a sheared gear grinding. But once in gear, both wheels would spin in opposing directions.

My thoughts are that the t-case went out on me, but I was hoping to get some feedback from some people on here. Any ideas would be great, thanks.

 

[Aphix]

I didnt have any oil spots in my garage that would indicate a leak, but could a t-case seal have blown out on the highway and drained it? Thus causing the oil I saw burning.

 

[volcomsnow245]

Is it the stock transmission/drivetrain?

 

[jtmcinder]

My diagnosis (with is a fancy word for "guess") so far: you blew your center and you were driving on your VC.

I know that you said that, in gear, when you turned one front, the other turned the other way. But if you lift just one front off the ground, can you turn it at all with the car in gear?

 

[JusMX141]

Transfer case locked up.

You may be able to tear it down and replace the bearings...I've done it before, but it's not recommended to repair a transfer case which actually suffered an oil-related failure because of the heat and stress put on the gears and the shaft.

Being a 1995 you should not have much trouble locating a working t-case.

 

[jtmcinder]

Transfer case locked up.

That's too easy. I like the more-complicated guess.

 

[Aphix]

I need to change the year of my Talon, the one I am driving is actually a 96. To my knowledge it is the stock transmission, but I got the car from some pretty shady guys who didnt speak much english.

If one tire is on the ground the other one will stay locked in place. But when it is in neutral. Both wheels can spin free of eachother and I can hear a grinding coming from the t-case area.

 

[jtmcinder]

Here's why I suggested it's the center diff and not the transfer case, even though the latter is probably more likely.

When you blow the transfer case entirely, then I don't see how the car moves at all. The VC on the center is between the input and the rear output. So, if you blow the transfer case, the input goes entirely to the rear output and the car doesn't move (since a blown transfer case disconnects the rear wheels).

In contrast, when you blow the center diff, the VC can still route torque to the rear wheels, so the car will still move. There have been several famous examples of drag-racers finishing runs on just their VC when they blow their two-spider OE center on launch.

Maybe you already answered this and my reading skilz are lousy, but I'd like to know if you can turn either front wheel with just that one wheel off the ground and the car in gear.

 

[Aphix]

When one wheel is being restrained the other wheel will not move while in gear. And thank you that writeup was very informative.

Little update, I got enough time to lift the rear and front end off the ground simultaneously and experiment with the car a little more. Now I dont have a very clear understanding of how the drivetrain works, but the rear end does not seem to be linked to the front end at all (which seems definitely wrong). While in gear, the front wheels will spin in opposing directions, and the rear wheels will do the same thing; but the front and rear are not linked together at all. I tried in both 2nd gear and reverse with the same effect.

 

[Aphix]

I ended up finding a huge crack in my transfer case, all fluid had been drained from it on the interstate. I haven't had time to drop the transfer case but it obviously needs replaced. My question now is, how can I determine that the center diff and other components of the drivetrain are either okay or broken?

 

[jtmcinder]

It's normal for the front and rear ends to behave independently, especially if you're unlucky enough to have an AWD with no rear VC. For both ends of the car, when you spin one wheel, the opposite turns the other way. This tells you that your front and rear diffs are fine, as are all of your axles.

Ignoring what the pinhead with the stars said (i.e., me) it seems you locked and blew your transfer case, as suggested by pretty much everyone else above.

As to checking the center diff: you really need a working transfer case to do this using the spin-the-wheels method. So I'd just focus on replacing that.

 

[Aphix]

That's good news, ill track down a t case and get it put on. Thanks for the help!

 

[Aphix]

Are an automatic transfer case and manual interchangeable?