4x4 Auto Engagement

[2Fish]

My 03 XLS 4.0 has a distinct "clunk" noise when automatically shifting to 4x4.

The other day we had a light snow I did not engage 4x4 hi, when the wheels slipped and the 4x4 auto engaged there was a distinct clunk when it engaged. Also, it appeared to engage and disengage often.

When I press the 4x4 hi button, it is a smooth inaudible engagement that stays in until the auto button is pressed.

I have heard that 4x4 auto is a ramp up engagement and wondering if the noise I am hearing is normal or am I to expect a repair?

 

[lincoln20012002]

My '04 does the same thing in auto 4x4. When taking off from a stop in the snow it clunks and bangs like something is really wrong. But every 3rd gen I have ever driven does that so I consider it "normal".

 

[outlawwv]

mine does that too - seems like it would have ripped something out by now

 

[Yamvip]

Mine too, don't like it at all. But its done it since new???

 

[E.B. Cornburner]

Mine did it too until I changed the fluid. At ~88,000 miles, the fluid that came out of it was like black tar. It was so bad that I took one suction gun's worth of fluid and flushed it straight thru before refilling it. A fresh drink of new Mercon V, and the difference is absolutely astounding! There's hardly any harshness or clunking anymore. Nice smooth engagement.

 

[outlawwv]

i'll have to get mine changed - i just don't think it could be good to have it shifting that violently especially at 16 degrees like it was today - i've been considering going to all synthetic fluids anyway -- any thoughts on that ?

 

[E.B. Cornburner]

i'll have to get mine changed - i just don't think it could be good to have it shifting that violently especially at 16 degrees like it was today - i've been considering going to all synthetic fluids anyway -- any thoughts on that ?

Mercon V is a synthetic fluid, and the recommended fluid for this transfer case. It's something you can easily do yourself. Pull the drain plug and let the old fluid drain into a pan, then remove the fill plug (reinstall the drain plug) and add new fluid till it's level with the top of the filler hole. Shouldn't take more than about 15 minutes.