What's wrong with my 4 Wheel Drive?

[roadhawg]

I have a 99 Ranger 4x4 4.0 with the electronic dial and not to long ago it quit working. When I turn the dial to 4hi, the 4x4 light comes on but it will not engage. When 4lo is selected, the gearing will drop for the rear but still no 4 wheel engagement. Does anybody have any ideas?

 

[Jspafford]

I moved this to a better location.

 

[Jspafford]

Your problem sounds like the pulse vacuum hub locks. The transfer case is working but the hubs are not locking the drivetrain to the front wheels.

 

[roadhawg]

Your problem sounds like the pulse vacuum hub locks. The transfer case is working but

Is there anything specific I should look at first such as a sensor or wire? I'm trying to avoid the mechanic.

 

[Jspafford]

Here is an article from the Tech Library that tells you how to permanantly lock them.. Hence turn them into what the 2001 and up trucks have. It will cause a very small loss in gas mileage, but then you will know they are locked.

Other option is something called an AVM hubs. It makes it so you can manually "Lock" your hubs like on older trucks. So when you needed 4WD you would have to make sure the hubs are locked in.

http://www.therangerstation.com/Magazine/Apr04/offroad.htm

 

[soylent_green]

Thank you Jspafford! That was exactly the link I was looking for, when I was looking for it!

On the AVM hubs, do you know if they will still fit under the chrome center caps?

 

[JaBradt85]

Thank you Jspafford! That was exactly the link I was looking for, when I was looking for it!

On the AVM hubs, do you know if they will still fit under the chrome center caps?

Yes.

 

[Jspafford]

http://www.tellico4x4.com/product_info.php/products_id/26509

 

[soylent_green]

Thanks guys!

 

[soylent_green]

So I took apart my drivers side hub lock and did the fix. Worked like a charm! The only problem is when I put it back together, it was leaking vacuum, so the pass. side would lock in, but unlock two blocks down the snowy road. A little hose pincher on the vacuum line to the drivers side fixed it until I can do the mod to the pass. side too.

 

[Jspafford]

You probably don't want to drive it long that way. It can damage the gears up front. If one wheel is locked and the other isint, the gears on the unlocked side are spinning twice as fast as the locked... therefore if you hit the 4x4 switch it will give the drivetrain a jolt.

I would get on the other hub very soon.

 

[4x4RangerGuy]

You probably don't want to drive it long that way. It can damage the gears up front. If one wheel is locked and the other isint, the gears on the unlocked side are spinning twice as fast as the locked... therefore if you hit the 4x4 switch it will give the drivetrain a jolt.

I would get on the other hub very soon.

+1

Lock in the other hub ASAP to prevent serious drivetrain damage.

 

[soylent_green]

Yeah, I left it like that yesterday so I could get into town during the snow storm, I fixed the pass. side this morning.

It actually hasn't been in 4x2 since saturday afternoon.

 

[MAKG]

You probably don't want to drive it long that way. It can damage the gears up front. If one wheel is locked and the other isint, the gears on the unlocked side are spinning twice as fast as the locked... therefore if you hit the 4x4 switch it will give the drivetrain a jolt.

I would get on the other hub very soon.

Huh? This makes no sense to me.

If either hub is unlocked, there is no effect of 4WD. The differential guts don't rotate unless the vehicle is turning. Unless one tire is locked up (braking?), but that would happen regardless of 4WD, and only if ABS is hosed. The axle is not clamped when open; it spins at the same rate as the other side (it's less resistance in the driveline to keep the differential guts steady). It just spins in the air.

Even if the truck is stuck, even with a perfectly working 4WD, you'll spin one front wheel and not the other (except if you have a front locker).

I'd still fix it right away, as it makes 4WD completely useless.

 

[Bent Bolt]

Huh? This makes no sense to me.

If either hub is unlocked, there is no effect of 4WD. The differential guts don't rotate unless the vehicle is turning. Unless one tire is locked up (braking?), but that would happen regardless of 4WD, and only if ABS is hosed. The axle is not clamped when open; it spins at the same rate as the other side (it's less resistance in the driveline to keep the differential guts steady). It just spins in the air.

Even if the truck is stuck, even with a perfectly working 4WD, you'll spin one front wheel and not the other (except if you have a front locker).

I'd still fix it right away, as it makes 4WD completely useless.

Because if one is locked and the other is not, the side gears in the front diff are spinning very fast which they were not designed to do for very long. Also, I doubt if it would be getting any lube as the gear oil level is below the side gears ( I think )