question about slipping

[expeowner]

So yesterday I was stuck on some ice and snow. The 4x4 is down at the moment. I'm trying to figure out what's wrong with that now. That's why I didn't put it in 4x4. So I was trying to get out and noticed that one tire was on the pavement and one on the snow. While stepping on the gas I noticed only the tire on the snow was spinning and it sounded almost like the knuckle in the rear was slipping. I'm guessing this is not good so I'm looking on input to see if this is ok or bad. As far as I know both tires should spin but maybe there's something I don't know. Thanks in advance for any and all help.

 

[Lightnig]

just so that I am clear, the issue is not with the 4wd, but with the rear axle? correct?

Left rear on ice and Right rear on dry and the left spins and right stays put?


Sounds exactly like an open diff to me. If your truck is equipped with an LSD then you have differential problems. Do you know for sure if your truck is equipped an LSD? If you are not positive, check the axle code on the drivers side front door.

 

[tonydiv]

A gentle application of the brakes (or even the e-brake) can help to send power to the spinning wheel when you have an open diff.

 

[FordandPolaris]

Like Lightnig said, you most likely have an open diff. In that situation, the torque energy takes the path of least resistance. If each tire is on a different surface (with different friction properties) the torque all goes to the side easiest to turn, in this case the one on ice.

What symptoms are you getting with the 4x4?

 

[toms89]

Agree with all the replys above.

With an open differential generally the power is transmitted to the wheel with the least traction. Since you mentioned one wheel did not spin at all this means that the wheel with zero traction was spinning twice as fast as normal.

The speed of the two wheels average out based on the input speed of the driveshaft. (What is indicated on your speedo) This is by design..

The spider gears are forced to turn by the wheel not spinning adding to the carrier case speed. The spinning of these spider gears can make a distinct whining sound which is what you likely heard.

 

[expeowner]

Sry about not replying. Been busy with work. The noise I heard was almost like the teeth on the gears catching and letting loose.

 

[tonydiv]

Um, no, it those gears let loose, then you'd hear a lot more grinding as the diff literally ate itself apart.

Let's start from the beginning:
Look on the door tag and see what it says under 'axle'.

 

[toms89]

Sry about not replying. Been busy with work. The noise I heard was almost like the teeth on the gears catching and letting loose.

Here's a decent animation of how an open differential operates:

How a Differential Works and Types of Differentials - YouTube

Generally the spider gears spin very little. Just enough to allow for speed differential between the two axles. An open differential with one wheel on asphalt and the other on ice forces the spider gears to spin rapidly as the one side gear is more or less locked in place.

I believe the noise you heard was simply the spider gears spinning at high rate of speed. Have heard it before plenty of times at the track (Not my car!!). If you happen to have traction lock it could have been eating up the clutches too. Tires spinning at high rate of speed on ice can whine as well.

 

[expeowner]

I really don't know what it is I heard but it wasn't winding. It was more like banging. As the wheel was spinning. It had me worried that the rear was going in it. Now I have noticed the past couple weeks that from a stop making a turn the truck almost feels like it's spinning the tires. It's hard to explain but it goes away as soon as I straighten out and it seems to do it turning to the left. I don't know if this could be related to this problem. There's really no noise but it does mimic the feeling in the truck that it was making while spinning on the ice. Sorry about all the questions and sounding like a pain but this is my only vehical and I do all my own work on the engine but as far as drivetrain I'm not really the knowledgeable except the usual stuff like shocks and tie rods and brakes and all that.

 

[expeowner]

I checked on the door and it doesn't say anything on there about lsd. Not sure what I'm looking for. I took a pic but can't upload from mobile and don't have a computer. It's a 97 expy 5.4l xlt. And as for the spinning tires feeling the best to decried it is almost like making a turn with 4wd engaged on dry pavement but the 4wd is currently down so I know it's not that. It won't engage. I get all the clicks and the light on the dash comes on but no engagement in the case acctually nothing from the case and I know it worked last winter because I used it so I'm hoping it's something simple.

 

[Lightnig]

no, the door tag will not specifically say LSD (or not)

It's the one with paint codes, body codes, VIN, etc...

You are looking for the axle code. The code needs to be looked up and will give you Rear end size (8.8" or 9.75"), axle ratio (3.73 or what ever), and if open or LSD diff.

If you look at the tag and provide the axle code listed, we can tell you exactly what was originally installed on your truck by the factory.


For example, my axle code is H6 which decodes to a 9.75" 3.73:1 ratio Limited Slip diff...






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[tonydiv]

We need that axle code in order to tell you if it's open or lsd.

 

[TexasAngel34]

mine says H9...

 

[JUST4FUN]

What this is looking like is you have a LSD ie.H9 with a broken axle. The noise you here is the broken axlegrinding together

 

[toms89]

Axle code should be on door jamb.

17 = 3.31 non-limited slip
19 = 3.55 non-limited slip
H6 = 3.73 limited slip
H7 = 3.31 limited slip
H9 = 3.55 limited slip

H9 is what TexasAngel mentioned she had, not the op.

While its not impossible I doubt seriously he broke an axle. If that was the case the vehicle would not want to move at all unless he had a spool in the rear. I assume the vehicle is no longer stuck and moving about normally?? He could burn up the clutches if he does indeed have a limited slip axle by spinning the one wheel on ice.

Not sure exactly what would cause the banging noise.

Maybe the u-joint due to the axle movement or possible the whole axle is torquing up creating movement in the suspension?? I would check the rear control arms to be sure they are in good condition. They have been known to rust out.

 

[JUST4FUN]

Axle code should be on door jamb.

17 = 3.31 non-limited slip
19 = 3.55 non-limited slip
H6 = 3.73 limited slip
H7 = 3.31 limited slip
H9 = 3.55 limited slip

H9 is what TexasAngel mentioned she had, not the op.

While its not impossible I doubt seriously he broke an axle. If that was the case the vehicle would not want to move at all unless he had a spool in the rear. I assume the vehicle is no longer stuck and moving about normally?? He could burn up the clutches if he does indeed have a limited slip axle by spinning the one wheel on ice.

Not sure exactly what would cause the banging noise.

Maybe the u-joint due to the axle movement or possible the whole axle is torquing up creating movement in the suspension?? I would check the rear control arms to be sure they are in good condition. They have been known to rust out.

Darn !I was looking on my phone and assumed it was the OP ,but this is the samething that happened to a friend LS with a broken axle it would still move but when he turned the rear would make a banging sound

 

[toms89]

Darn !I was looking on my phone and assumed it was the OP ,but this is the samething that happened to a friend LS with a broken axle it would still move but when he turned the rear would make a banging sound

Interesting. With a 9.75 trac lok rear or aftermarket locker??

The 9.75 axles at least are pretty hefty as well. I have not been concerned with my axles drag racing because there are lightnings putting far more power through them than I. The 8.8 is a different story. Curious how your friend broke one.

 

[tonydiv]

On C-clip axles, if the axle shaft beaks, the entire wheel will slide out. In other words... you'll notice the problem.

 

[JUST4FUN]

Yea if its a drum brake but disc brakes will hold ,with the calipers in place

 

[JUST4FUN]

Interesting. With a 9.75 trac lok rear or aftermarket locker??

The 9.75 axles at least are pretty hefty as well. I have not been concerned with my axles drag racing because there are lightnings putting far more power through them than I. The 8.8 is a different story. Curious how your friend broke one.

Responding to a fire call arounda corner hit ice patch and spun a tire high speed spinning caught a dry spot snap went the axle brake parts held it in till we took it apart that night