Transfer Case 'Shudder'

[gabateman]

Hey guys...new to the forum with a tech question on a vehicle I just purchased.

'02 Explorer XLT w/ 4.6L and Auto 4wd

I have been recently experiencing a 'shudder' in the vehicle, once warmed up after 15-20 miles. Vehicle exhibits shudder through the middle of each gear, not at the shift points.

Thought it may be a transmission issue, but the more I drove it, the shudder feels more like it is coming from the front end as if the AWD is trying to engage? If I understand correctly, there is a 5% load on the front diff at all times?

So...I've read a few posts regarding the BWM, so I took the step and simply unplugged the transfer case module and...the shudder went away.

Any thoughts or experience out there with this vehicle? As with everyone I'm sure, would appreciate any feedback...

Thanks,
Gary

 

[drdoom]

Do all four tires match EXACTLY?

 

[gabateman]

Yes...(4) brand new Goodyear Futura tires. Another note, by shifting into 4WD high mode, the shudder went away as well.

Thanks

 

[drdoom]

Have you tried changing the fluid? Only reasons I mentioned is 1. It doesn't shudder when cold. 2. It may need changing anyhow. I would suspect you have a bad 4x4 module though.

 

[gabateman]

So...thanks for the suggestion on the fluid. I ended up solving (2) issues at one time.

Turns out the transfer case rear seal had a very slow leak and the transfer case was low on ATF. So I replaced the seal, changed the fluid, and all seems well at this time.

In addition, I had a speed-sensitive low pitch grinding near the same area, thought is was possibly the rear end transferring up the frame rail. Turns out the low transfer case fluid was also causing excessive chain noise in the transfer case.

Problem solved for now...thanks for the reply and help. The truck is in really good shape in need of a couple maintenance services. Now onto the noisy IAC...damn, that Motorcraft part is pricey!

Gary

 

[drdoom]

Good job and thanks for updating.