Help Needed 4x4 issues....

[AKmud]

I have a 2000 F350 4x4 PSD with a 6spd manual. Yesterday was pretty snowy and slick so I was running in 4wd. I noticed when turning I was getting a LOT of chatter out of the front end. I know this is normal to some degree because of the different turning radius, but this was to the point of almost not making turns (like into a driveway or a 90* street) unless I was just crawling. The 'chatter' was causing my front end to skid and wouldn't let me make the turn!

It feels to me like there is NO action in the front differential and it is basically acting like a straight axle.

Any ideas? If I don't get this figured out, it is going to be a LONG winter!!

 

[BJS]

sounds like your spider gears are not working correctly. Pull the front diff cover off and inspect the inside. Also check your front u-joints.

 

[95_stroker]

Yup, sounds like something is locked up in that differential. Have you had a chance to look at it yet?

 

[AKmud]

No, I haven't opened it up yet. The weather cleared up and now I will probably forget about it until the next dump .

I have manual locking hubs and have been running with them in the lock position even though I'm in 2wd simply because I'm lazy and want to be able to throw it into 4x4 quickly. I know this turns the front drivetrain forward of the t-case, but if the diff wasn't working properly, wouldn't it do the same chattering since the hubs are locked in?

Also, is the front diff similar to a posi-trac rear end in that it needs additive to make it slip?

 

[Crumm]

if the diff wasn't working properly, wouldn't it do the same chattering since the hubs are locked in?

Probably would. If the spider gears were locked up then the front axle would be locked together and do some serious binding. Since it does it so bad when the t-case is engaged I wonder if someone at the factory or elsewhere may have installed different ratio gears in the front or back? Did you purchase this truck new? I would jack up the truck and count driveline/tire revolutions on the front and back to see if they are the same.

Also, is the front diff similar to a posi-trac rear end in that it needs additive to make it slip?

Limited slip in the front axle is very uncommon.

 

[JLDickmon]

I got a 12 pack of Leinenkugel's Original in cans that says it's got an axle joint (or both) that needs to be replaced.

 

[AKmud]

Probably would. If the spider gears were locked up then the front axle would be locked together and do some serious binding. Since it does it so bad when the t-case is engaged I wonder if someone at the factory or elsewhere may have installed different ratio gears in the front or back? Did you purchase this truck new? I would jack up the truck and count driveline/tire revolutions on the front and back to see if they are the same.

I just bought it used from Kendall this spring. About a month after I got it, I found the 4x4 wasn't working (dealer wouldn't fix it.....) and it ended up being one of the hubs had been taken apart and put back together wrong. I fixed that and then noticed how rough the 4x4 was. Maybe since someone had the hubs (aftermarket BTW) apart, they had 4x4 issues too.

 

[Frankenstien]

If you have after market hubs.... it is possible that some may have done a dynatrac upgrade for you. but as JL states check your Axel U-Joints for problems.

 

[chris o.]

are all the tires the same same size? if not,(like a spare) it will mess some stuff up in 4x4.

 

[Clyde99]

I cast a vote for bad axle u-joints as well. If one is loose/worn it will cause binding/grinding/noise issues.