Jbrewer7

Hey I have a 2001 ford f150 4x4 and something in my rear is making a slight popping noise and you can only hear it when goin very slow but when I first get in it in the morning times it take a minute to get goin down the road before you start hearing it, I jacked the rear up and put the truck in drive and didn’t hear it, it’s only happens when’s the tires are on the ground, all help would be appreciated

white89gt

Is it an actual pop, or a click? I would inspect the U-joint if it's a pop. If it's a click, again check the U-joint, but could also be the spider gears inside clicking. They wear out over time.

Dee Veloper

Is it randomly occurring or is it a repetitious cyclical occurrence ?

Jbrewer7

no it happens everytime I drive it but it takes a minute before I can start hearing it

Dee Veloper

Understood. But when it occurs does it continue at random intervals or is it persistent in a cyclical manner which coincides with the speed of the vehicle?

Jbrew

Try servicing the slip yoke thoroughly w/brake cleaner....clean it. Then grease the spline with a very thin coat of teflon type grease.

manicmechanic007

Maybe
Limited slip frictions chattering
Maybe
Add more friction modifier

Jbrew

...

Snake plissken

jbrew, MOST people are not going to have a clue what your talking about but I do. I had this issue way back when I bought my 97 new. While under warranty I went thru maybe one slip yoke a year. Ford just replaced it but they NEVER could figure out why my truck had this problem. It was still doing this when it went out of warranty and then it was my problem. Never figured it out. I still have that blueish Teflon can of grease. It was so consistent I decided to remove the oem transfercase and get a MANUAL shift ATLAS and have my driveshaft redesigned without a SLIPYOKE. No more ESOF.
Never had any problems after that.
Also, I can shift in and out of 4x4 EASY. It never gets stuck.
I figure ford redesigned that area with newer models but I don't know.
My 2000 has esof and I have not seen any issues with it. Not saying that's this guy's problem but hopefully it's not.
I always thought the slip yoke issue could have been from the driveshaft ANGLE but I don't know.
First time I've heard about it in years.

Jbrew

Yep. that's the grease and spot on about the alignment as well. Fairly easy to readjust via tranny mount bolts. It's surprising how far the transmission and t-case can move from left to right when connected to the motor. All it takes is couple loose t-mount bolts.

Good Post Snake!