4WD Question

[CarDude225]

Can someone tell me what type of 4WD is used on the Suburbans? Is it the type that the gearbox locks the front and rear axels, and also the left and right are locked together? Or is it the other type that allows turning without tire slippage?

Is there a name for this type of 4WD?

Thanks. Just trying to understand how the 4WD system works to see if I even want to bother with purchasing a used 4WD (may just stick with a 2WD Burb).

[j cAT]

Originally Posted by CarDude225

Can someone tell me what type of 4WD is used on the Suburbans? Is it the type that the gearbox locks the front and rear axels, and also the left and right are locked together? Or is it the other type that allows turning without tire slippage?

Is there a name for this type of 4WD?

Thanks. Just trying to understand how the 4WD system works to see if I even want to bother with purchasing a used 4WD (may just stick with a 2WD Burb).

the front axles are free wheeling until 4x4 is activated....then the axles are locked together.... in the rear the differential is either limited slip or locking.... it does not matter 4x4 or 2wd this does not change.... I perfer locking diff ,this is because unless a slip is sensed the vehicle only has 1 wheel drive ......also this helps reduce wear of rear diff. as limited slip gets worn when making turns......with the vin of vehicle you can find out what type of diff the vehicle has.....thru dealer....I also prefer AUTO 4X4 when road is slippery, as this is the most efficient use of vehicle operation with a minimum of drive train wear.......

[CarDude225]

OK thanks.

Is locking differential in the back the most common, with limited slip being an upgrade?

But with locking don't your tires chirp in the rear due to same-speed-rotation-while-turning causing additional wear on the rear tires?

[j cAT]

Originally Posted by CarDude225

OK thanks.

Is locking differential in the back the most common, with limited slip being an upgrade?

But with locking don't your tires chirp in the rear due to same-speed-rotation-while-turning causing additional wear on the rear tires?

i have both types locking on truck limited slip on car..... locking only locks when slip is detected sometimes if one wheel is on ice and the other on solid pavement you will get a forceful application of the locking ...with limited slip you must not accelerate hard from stop when turning or as you stated the wheels will chirp and you will get a slight rear end shake....because the wheel on the inside of the turn is unable to rotate as the other side can...with locking this rarely occurs as after the slip passes the diff quickly unlocks and your back to 1 wheel drive.....I would say limited slip is not an up grade.....as this type in ice and snow is of little help.... on solid pavement and not turning it is very good compared to non locking/limited slip diff's....

[CarDude225]

Originally Posted by j cAT

...with locking this rarely occurs as after the slip passes the diff quickly unlocks and your back to 1 wheel drive

You mention that you go back to 1 wheel drive with locking type diff, and for several days I haven't been able to understand this. But I ran across an article tonight:

An observer will simply see one stationary wheel and one spinning wheel. It will not be obvious that both wheels are generating the same torque (i.e. both wheels are in fact pushing equally, despite the difference in rotational speed). This has led to a widely held misconception that a vehicle with a differential is really only "one-wheel-drive". In fact, a normal differential always provides equal torque to both driven wheels (unless it is a locking, torque-biasing, or limited slip type).
[ From http://en.wikipedia.org/wiki/Differential_(mechanics)) ]

Did I misunderstand you?

[j cAT]

Originally Posted by CarDude225

You mention that you go back to 1 wheel drive with locking type diff, and for several days I haven't been able to understand this. But I ran across an article tonight:

An observer will simply see one stationary wheel and one spinning wheel. It will not be obvious that both wheels are generating the same torque (i.e. both wheels are in fact pushing equally, despite the difference in rotational speed). This has led to a widely held misconception that a vehicle with a differential is really only "one-wheel-drive". In fact, a normal differential always provides equal torque to both driven wheels (unless it is a locking, torque-biasing, or limited slip type).
[ From http://en.wikipedia.org/wiki/Differential_(mechanics)) ]

Did I misunderstand you?

if i remove both rear wheels off the ground on the locking differential and move the right wheel,,, only the right wheel will move. but if i move it too much then the other wheel will start to move and stay locked until so many revolutions of equal rotation.


on the limited slip both wheels off the ground both wheels will rotate and with 2 people one on each side you will see that the wheels are always engaged if you drop one wheel to the ground so it can't rotate and then put a torque wrench on wheel off the ground the wheel off the ground should not rotate with a force of 50ft lbs of torque applied to lug nut...above that the wheel will rotate but with this LIMITED ENGAGEMENT....


on the locked it is locked solid and after you rotate the rear wheels on the locking diff drop vehicle to ground when taking a hard left or right you will feel the wheels jumping until the rear wheels unlock...when i was repairing my defectively designed GM parking brake for the first time i found this out...