Heard an awful "POW!!!" noise

Your fatal error was using 4 wheel drive (especially 4 LOW) on a hard surface while in a turn. A hard turn in 4 low is begging for something to break. NEVER EVER do that again. If all is well now count it as a lesson learned. RTFM about using 4x4........

That's your u-joints at the front wheels telling you not to turn so sharply with 4WD engaged. My Bronco did that occasionally, as there are limits to how far you can bend a u-joint when it is being rotated under load. When a u-joint driven shaft is disengaged at the hub, the idle driveshaft will orient itself to the proper axis to simply act as a hinge when the wheels are turned left and right, allowing you to turn the wheels sharply throughout the full range of their steering travel. Once you engage that axle at the hub, it rotates with the wheel and the u-joints ability to bend is limited considerably. When you force a rotating u-joint to bend beyond its capabilities, it will bind and flex and actually try to straighten out the wheel to release the bound up energy; this is what caused the steering wheel to be yanked from your hands. It's always good practice to avoid this, as it is just brutal on the parts up there! Just remember not to turn too sharply when 4WD is engaged.

Cheers

-- Sent to you by Ken at kenwho?@sympatico.ca Replace "who?" with "b2" for e-mail

sounds like you broke an axle

By being in 4wd on a hard surface, you experienced a serious drivetrain bind. If you had been pointed straight ahead, it wouldn't have happened. Because you had your wheel cranked hard, the front and rear tires weren't wanting to rotate at the same speed, but your transfercase was making them do it anyway.

The loud "pow" was a release of that bind. If you are lucky, nothing broke and the bind was ultimately released through tire slippage. If not so lucky, things will get more expensive..... Maybe you blew a hub. Maybe an axleshaft or something at the diff. Maybe something in the T-case itself.

Assuming it seems to be driving OK now, you need to see if something was broke. Find a place where you can put it in 4x4 and see if you have any bad noises and/or your front wheels are being driven. A steep dirt hill would be my choice.

If you find out it is broke, I wouldn't mention how you did it to the service department. I'm sure they could classify the episode as "misuse" and not cover the repair.

Matt

Bad, Bad, Bad. A part time case, in 4-low, in granny gear, on pavement=exploding U joints, grenading T cases, etc. You broke something big time.

Never use part-time 4-wheel drive on pavement. You damn sure didn't need 4-lo to go over a curb.

• * * Matt Macchiarolo
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You need to reread all the advice already given to you. It has nothing to do with a limited slip differential, it has everything to do with makeing a sharp turn on a dry paved road while in 4 wheel drive. When you do that you create a serious bind in the drivetrain which usually unloads by something "giving" hopefully the tires. Keep it up and you will soon (if not already) learn an expensive lesson. Read the owners manual and remember that your warranty doesn't cover abuse. Bob

Thanks for ringing in. Seems my mistake is obvious, I just didn't think it was that big of a deal for 10 feet or so...lesson learned. Seemed to drive ok on two short trips today, will crawl underneath and look over the drive train tomorrow morning. Hopefully I got away without damage but it was a really loud bang, so I reckon it's probable something is broke.

As far as busted axles, hubs and the like wouldn't that show up in an odd noise, or a change in handling? I should be able to see a busted U-joint, cracked T-case but aside from tearing everything apart...how do I make sure the internals are ok?

-BunnMan

OK, the suspense was killing me and I couldn't wait until morning. I just came in from checking underneath and everything looks ok. No cracks, leaks, or suspicious looking things along the drivetrain or front axle. When I spin one u-joint up front, the other side counters it just like it's supposed to so I assume the axles are still intact. I'm not sure I can rule out hub damage yet though. I tried to rotate the hubs from "auto" to "manual" and couldn't budge either side. They always have been rather stiff and I know other SD owners who have the same problem so I doubt it is a result of my recent stupidity. I would like to free them up if anyone has a tip for doing so. Maybe I should just go out and buy a set of Warn manual hubs and lose the factory autos I guess.

-BunnMan

One thing's for sure, low range can be very handy, but you have to have manual hubs to use it when there's plenty of traction. That's one big reason to NOT have knob-on-the-dash 4 wheel drive.

No kidding, I agree 100%. I would certainly prefer to have manual hubs and a transfer shift lever on the floor. I bought the truck used and had a terrible time finding a 6-speed power stroke 4x4 extended cab. Once I found it...I jumped on it. The $15,000 savings over buying a new one was worth putting up with the knob on the dash for me :)

-BunnMan