4 wheel drive question

My '95 T100 (see my thread on "Restoring a T100") has "on the fly" four wheel drive that goes INTO 4 wheel drive okay, but won't come OUT of 4 wheel drive when I move the shift lever back to 2 wheel drive.

It *will* revert to 2 wheel drive instantly if I put the truck (it's a

5-speed manual) in reverse.

I suspect the 4 wheel drive has not been used much in recent years, and is in need of "exercise" -- but can anyone interpret what's happening here from the symptoms I describe? Is this something I can fix? If so, how?

Thanks!

-- Jay Honeck Iowa City, IA '95 T100 4x4 Extended Cab

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"Your Aviation Destination"

Reply to
Jay Honeck
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I believe this is common Jay. I know it is with the automatic hubs. Your truck probably has the ADD system:

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Here is another link thatmight interest you:
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Reply to
Jarhead

My Toyota Tacoma is 2wd. My 4WD vehicle is a 1963 Willys Wagon with a small-block Chevy conversion, so fair warning - I'm not really able to give you the definitive answer on your T100.

That said, this sounds perfectly normal. Reversing unloads the drivetrain, allowing the gears to come out of engagement with each other.

BTW shifing the Willys in a similar situation is like cold-welding steel by muscular force alone, but at least it has Honest-to-John-Wayne shift levers not some push button on the dash.

Reply to
Mike Harris

The couplings in the 4X4 system get bound up by differential torque between the axles - when you turn a corner the front wheels travel farther around the circle than the rear wheels do. When you back up, you reverse the process long enough for the couplings to pop free.

DO NOT even TRY locking the 4WD on dry pavement, period. The only cars that can do that safely have 'All Wheel Drive' designs with a center differential in the transfer case.

Save the 4WD usage or tests for loose dirt, gravel, sandy, muddy, snowy, sloppy conditions ONLY, when the tires can easily slip some to relieve the stresses. If the wheels can't slip and relieve that stress and it builds up enough you WILL snap something - either something cheap like a U-joint, or expensive like pieces inside the transfer case, snapping an axle shaft or shattering a front locking hub, or twisting a driveshaft like a piece of licorice.

-->--

Reply to
Bruce L. Bergman

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