I engaged 4 wheel drive in my truck today and noticed when I cut the steering hard and tried to drive forward, it felt like something was in a bind. It also appeared that the right front end was folding under, like something was collapsing. The truck would move, but felt like it was trying to pull an immovable force. It feels fine when driving straight ahead. It's alright in 2 wheel all the time. Anyone have any ideas what my problem might be?

 

Don't mean to talk down to ya, but you weren't on the pavement when this happened were you? If so, that is your problem.

 

98Lariat

I own a 97' F150 4X4 4.6L. Are you saying that if he was on pavement that this is what would happen? I know that when I cut my wheels hard in 4wd on pavement, my tires would squeal from the resistance. But I try to avoid making sharp turns on pavement while in 4wd because of this. I'm afraid of breaking a shaft or anything else in the front end. I also understand that this is a common thing with these 4x4's.

BJ

 

The reason turning on pavement is so bad is because there is no give to it. The way the 4x4 works is that both wheels turn at the same speed when they're being powered. When you're in 2wd the wheels turn at different speeds. This creates the binding since one of the wheels has to slip on the surface to allow the truck to turn. In mud or other soft surfaces where 4x4 is supposed to be used you don't notice this since the surface is soft and allows the tires to slip some. It won't destroy your 4x4 to turn sharp on pavement every now and then, but its not very good for it so it should be avoided if at all possible. What you felt was normal.

 

Are you saying the front differential is locked in fwd? I thought it was open. I'm pretty sure the back stays open. My thinking was that one front and one rear should be locked and if it's on the same side then they should be turning about the same speed.

 

Ok, I didn't phrase that right. The front does stay open, but when you power the front wheels and then turn it causes the binding sensation. Only one front wheel gets power.

 

You shouldn't run in manual 4X4 on solid pavement. There is no give to overcome the locking and you are putting your drivetrain in a bind. You should only engage manual 4x4 on dirt, ice etc. where the inside wheel slippage that is needed to turn can occur.

 

BeeJae & 97F250,

It is NEVER a good idea to engage you 4wd on dry pavement(in a straight line is ok). It puts serious strain on you drivetrain to do so. Your 4 wheels are each traveling a different distance while traveling through a turn, 4wd attempts to apply power to all 4 wheels in some form(not like a locker but if you get in the really slippery stuff they will all spin assuming you have a L/S rear end). When you apply power to all 4 wheels but they are all trying to travel a differnet distance in a turn a magical force called drivetrain bind occurs. AWD vehicles have a clutch type devise in the transfer case to prevent this, our transfer case spins both driveshaft equally. As far as broken driveshafts etc being a problem in these trucks, I have wheeled mine pretty hard a few times in the slippery stuff(where 4wd is intended to be used) and never broken anything. I have not attempted any rock crawling because they aren't made for that type of terrian, but they LOVE the mud and snow!

 

Thanks for the replies. This is my first 4x4 and I'm not well educated on 4x4 technology and the information given makes sense. The reason for engaging 4x4 was because of an incident the previous day. While driving in rain I made a left at an intersection and nearly looped the truck when the back end broke loose. This had happened a couple of times before. This in spite of almost new tires and being extra careful. So the next day I was thinking if I used 4x4 I might avoid this occuring again. The pavement was quite wet, but evidently not slippery enough to avoid the "binding" of the drivetrain.

 

Turning on the 4x4 will NOT allow you to avoid the situation you were in the other day. The problem would come from you giving the truck too much gas in the corner, going into the corner too fast, or you having a limited slip diff, or a combination of all 3. Bottom line this is the nature of the beast. You've got a light rear end with a rear drive vehicle, and if you have the stock tires they flat out suck especially in the rain. 4x4 will do absolutely nothing to help you in rainy conditions. It may help a little bit on ice, but it will only do marginal good to help you gain a little traction, but will not really help you avoid much sliding. The same goes for snow or mud.


What the 4x4 WILL help you with is if you're on a slick surface and you turn the wheels the driving front wheels will help you try and gain some momentum in a the direction you're turning to help you turn a little better. If you have a 2wd and you turn since the front wheels aren't powered they can just slide along and not help you change your direction of momentum. Keep in mind though that this will only help you if you can gain some traction to let your front wheels grip. Otherwise it will do the same as a 2wd. The reason this won't help you turn in rainy conditions is because you have a good surface to gain traction on (the road) but if your front end starts sliding in a turn 4x4 won't help you because you're hydroplaning and you won't grab any traction powered or not.


4x4 can help in SOME situations when turning or trying to gain forward momentum, but it will do NOTHING to keep your back end from breaking loose.

 

97f250,
the only fix too your problem is in getting familiar with your truck.

rain + speed + slick surface + corner = spinout
(in any vehicle you drive.)

when you add a 4X4 to this problem, the only advantage you get is that you can throw the slick stuff with all four tires. four wheel drive biggest benift is in it's ablity to start moveing and continue moveing when 2 wheel drive vehicles wont. they do very little to help in control or stopping. ecspecialy at speed.

as far as the drive line binde (i call it crabing) your truck does it in two wheel drive as well you just hear it as tire squeel, cause your slideing which ever tire has less traction. if you do it with 4X4 engaged the tire does not slide cause it's forced to turn under power. and the inside front wheel assemly should lean to help minimize this. as long as theres no popping noises you should be fine(and the assembly straightens back up when straight). and stay lite on the excellerator when your in 4X4 and the wheels are at the stops.

i would suggest you visit your local 4X4 store, 4X4 club they would probly answer any of your questions.