Jerking when 4x4 is engaged on '97 Expl.

[Wingnut]

When my '97 Stock Explorer is in 4wd there is a violent jerking in the front end while making a 1/2 turn. I know it is normal to have some tension on a heavy turn but I can't even U-turn on a 4 lane road in 4wd. When 4wd is disengaged, there is no problem. What could it be?

 

[DrewP]

Wingnut,

Are you driving with 4WD on dry pavement? If you don't have control-trac or are in low range and are making u-turns on pavement then you are causing your system to bind. Unlike cars with AWD, you don't have a differential between the front and rear wheels to handle the different speeds when making turns. If this doesn't answer it, then I guess I don't know.

Hope this helps.

Drew

 

[Robert]

If you are trying this on pavement then it is your front end telling you that your wallet is about to become a lot lighter! When you are in 4x4 (high/low), your front and rear tires need to be able to turn at different speeds when turning. Your front tires need to take a longer path than your rear tires, but need to do it in the same amount of time. On dirt, sand, mud, or snow, the surfaces will give allowing your tires to slip. Pavement does not allow the tires to slip nearly as easily which usually will result in something in your drivline breaking instead.

Robert

 

[Dr.Doug]

As I previosuly posted on a similiar question:

The fact is, there is no problem with you Explorer. When the 4X4 is engaged, the hubs become locked to the axle and turn at the same exact speed. When the wheels are turned, one of the wheels will naturally spin faster and attempt to spin, through the axle, the other wheel at the same speed. For this reason, in 4X4 mode, the vehicle bucks and jumps when this is done on a non-slip surface. In low range, gearing amplifies this.

The bottom line is, DONT EVER HAVE THE VEHICLE IN 4X4 ON A DRY SURFACE !!! You will cause SEVERE damage to the 4X4 components,
if you continue to do this. I personally, only engage 4X4 in snow or mud. When I reach the dry or CLEARED non-slip surface, I disengage the 4X4 and reverse 10 feet to UNLOCK the hubs from the axle.

Good luck, Doug

 

[Wingnut]

I do have The control track feature. I have read that it is OK to engage 4high at any speed and 4h can be used on any surface while towing. When I pull my boat I don't expect to go straight there without making a turn. I appreciate everyone's responses, please continue. For this does not seem like normal 4wd performance.

 

[SteveVB]

Wingnut

The jerking you feel is the front wheels grabbing the pavement. Everything that has been said previously is true, when you are turning the front wheels the speeds at all four wheels are different and something has to slip to let the drivetrain catch up. Why do you need four wheel drive to tow a boat? Just put it in four wheel drive getting up and down the ramp. I put my 4wd vehicles in 4wd at least twice amonth for a few miles, and its usually as Im driving them down the road(pavement) so I dont think using 4wd on pavement is taboo, but I wouldnt do sharp turns. If I have to be in 4wd and need to do a 3 point turn on a hard surface I make it a 6 point turn, so I wont bind the drive train.
Tight turns in 4wd will grab and jerk on any surface- something has to slip, the surface you are on, the tires, or something in the driveline. The surface is best, tires will wear very, very quickly, usually the steering knuckle ujoint or in your case the cv joint will fail. Four wheel drive on pavement is OK if you are careful, but unless you have a really good reason to be in 4wd keep it in 2wd. Its much easier on your vehicle.

Steve VB
91 Navajo

 

[Robert]

What you are experiencing is normal 4 wheel drive behavior for a part time 4 wheel drive, right before it breaks and costs a lot of money to fix, which by the way is also normal 4 wheel drive behavior for a part time 4 wheel drive. When you move your selector from Auto to High or Low, you are putting it in the part time mode. It should not be used on hard, non-slippery surfaces (especially when turning). Many people will put theirs in High once in a while while on the pavement to keep things working when they don't frequent dirt roads. That is OK as long as you don't make sharp turns. There is on reason for you to have it in 4 wheel drive when you are pulling a boat except to pull it up and down the ramp. Take it out of 4 wheel drive as soon as you get back up to the top of the ramp before you turn. You will probably find that you won't even need to put it in High/Low since your '97 has Auto as the main driving mode. My '97 reacts very quickly in Auto and starts pulling with the front tires. It will resort back to 2 wheel drive a short time after the slipping has stopped. I would also quit reading whatever it was that said you should put it in 4 wheel drive when pulling a boat, or at least go back and re-read it to make sure you understood it correctly. You are also limited to shifing into High at about 50MPH. Many people take it to mean "at any speed", but it should be stated "at any speed up to 50MPH". Of course if you are going more than 50MPH you probably won't need 4 wheel drive unless you are suicidal.

Robert