HAy All:

2000 F250 SD 4x4 v10, when I enguage 4x4, I can hear it "both low and high"
But was testing it today on a gravel road, and the rear tires would spin and it just didn't seem like kthe front were doing anything.
whis was with a loaded trailer about 2 tons.

I'm new to 4x4, " as you can tell " am I expecting too much or is it NOT working ?




Thanks

 

If you have automatic hubs, you probably have a vacuum problem.

 

BUT why am I hearing it enguage, and the light indacator on the dash says 4x4

 

Well I am not 100% sure, but on my truck, going into 4HI does not make any noise when you are inside the truck, but you can hear it lock into 4LO. Did you switch it while in drive, the 4HI should be an on the go option, but put it into nuetral while in 4WD or A4WD or whatever, and then switch into 4x4 and see if that works.

 

Was not sure how it works, so with window down, " and trying to listen " while in nutral I place it in high, and got the click and the indacator on the dash, tried it and only rear wheels spun. went back to nutral put it in low, " herd the click" "got the indicator light "
it again spun rear tires, Just not sure how to check if it's in 4x4, and or should the front tires spin, while on this gravel road.

Just a little confused,

thanks

 

It is probably engaging the transfer case, and that turns the dash light on and you can sometimes hear the engagement. But your hubs may not be engaging, which you cannot hear, and there is no sensor to alert you. Lots of things can go wrong with the front hubs.

To test - first try using 4WD on some hard dirt at low speed and turn the steering wheel into a hard turn. You should feel some bucking as the wheels try to equalize the turning radius by slipping. If don't feel anything like that, you can be pretty certain that something is not engaged.

Then move on to jacking up the front wheels on jack stands while 4WD is engaged. If everything is engaged like it should be, you cannot turn a front wheel by hand. If you can turn a front wheel, then look at the front drive shaft while turning the wheel. If the transfer case is engaged, the shaft will not be turning with the wheel, and that tells you one or both hubs are not engaged. If the drive shaft does turn, then the transfer case is not engaged.

Chances are it is the hubs, and you have a vacuum leak or crusty corroded hubs. It only takes one failed hub to lose all front wheel drive because it is an open differential.

 

quick and easy check is after u think u have 4WD engaged get out and grab the stub axles and see if u can turn em..

u shouldnt be able to... if u can then the hubs arent engaging properly...

 

Ok, Thanks Guys, being new to this stuff I sometimes get confused. the tips are GREAT and will check it tomorrow.


Thanks again

 

no worries, thats whats so great about a site like this...

always glad to help..

 

Hate to correct you but;

1. One wheel doesn't attempt to equalize the turning radius while in 4WD.

2. With both wheels jacked up in front, both hubs locked, and t-case engaged, you can turn one wheel by hand.

 

Get on a gravel road, step on the brake and the gas, let go of the brake, spin out for about 5 feet and go look at your tracks or; get on dry pavement, put it in 4W hi, turn slowly and sharply. If the truck wiggles and bucks you in in 4WD.

 

No problem, I'm wrong all the time and welcome correction.

Not what I said. The equalization is between front and rear, but is necessary because of the turning radius. Side to side is equalized in the differential. But thanks for clarifying the point.

You are correct, one wheel could turn because of the open diff. Usually the other wheel would be turning in reverse rotation.

 

Actually the bucking and wiggly feel is because when the u-joints are at an angle the driven axle speeds up and slows down with every revolution in an attempt to maintain the same RPM as the driving axle due to the fluctuating axis plane of the joint. This small variance in speed is transferred to the much larger tires which also vary in speed with every revolution as they turn which gives the bucking sensation.
Any discrepancy beween the front and rear wheels on a turn will be absorbed by the the open differentials ability to allow for varying wheel speeds.

 

Not true, and there are plenty of broken transfer cases to prove it.

 

I'm assuming the gears and tires match. While on a turn, the inside 2 wheels follow 1 track at 1 speed and the outer 2 follow another track at 1 speed. Some situations could cause undue strain while off-roading to the t-case but this is another issue.