MercedesTech-

Help me understand. Is the differential actually built in to the ring and pinion on the FX4 Rear, or is it a separate mechanism?

Also, he said the axles were probably destroyed, do you think this is possibility?

 

how would i know if my rear angles are okay??

 

You can do it yourself, or take it to Ford and have them check it for you. They should be able to do it while you wait.

 

I'll do my best: The differential is the name given to the Ring and pinion and the spider gears and all the other little stuff inside. When you look at your rear end, that big pumpkin looking bulb right in the middle, thats the differential (everything inside it helps make the differential work) The axles could have taken a beating. They have little teeth that are on each end of the axles. These teeth stick into the differential and the teeth mesh up with the "spider gears" or other people call em "planetary gears". These are what spin the axles. If the teeth on the axles took a beating, you could end up needing new ones. If you do get new ones, look into aftermarket Chromoly shafts. Strong and much more resistant to breakage. Basically the drive shaft goes in, spins the pinion gear. Pinion gear makes the ring gear spin. Once the ring gear begins to spin you "carrier" will also spin making the spider gears spin. When they spin they grab the axles, making them spin giving the power out to your tires. I will try and get some pics for you. Its hard to say what "could have broke" with out seeing everything that happened. Like I said, best bet would be having someone, non biased who knows his stuff real good take a look.

 

Where do you measure the angle from?

 

Not to jack the thread or anything but I might be looking for some 4:56 gears. Let me know how cheap

 

Thanks man,

I am going to get that cover off tomorrow I think unless 4WP will take a look at it for me.

I will post an update

 

keep us all updated, i got the stg 2 kit as well. i hope everythings all right and somebody covers it for ya.

 

It looks like no one is going to cover it completely. 4WP did agree to get it up on the lift today, and disassemble it so I can see all the parts with my own eyes.

They also agreed to help me out on the total cost and will replace the parts with stronger more durable parts than Ford will.

The good news is, I was planning on strengthening my rear end anyway. I was just not planning on doing it right now!

 

Its good to hear someone is stepping up, but remember, NEVER take their first offer. Once its all taken apart and your looking at it, tell them straight and say looks to me like it was the "installer's error" that caused this and therefore the "installer" should have to cover it. Don't give up man, they have TONS of cash, and if that specific shop wont help, call head quarters and complain to them. Remember closed mouths never get fed and the loudest squeeky wheel will get greased first. This sounds unacceptable to me, sounds like someone else F*cked up your rear-end and will only "help" on the cost. Good luck man, and if after looking at it you have ANY questions, feel free to ask. Try and take PLENTY of pictures too. It will help us give you answers and it may help prove your in the RIGHT. again, goodluck man.

 

Here is an update! It is all good news.

Took the truck to 4WP yesterday, and spent most of the day with them. All the techs were super busy, but they found time to get my truck on the lift and get the rear end taken apart.

We check the rear angles on the drive shaft. The shop manager explains to me since they used lift blocks they in no way changed the angle. He does all these fancy calculations and we come to conclude the pinion angle is correct. The only angle that changed was the driveshaft angle, which was only at 10 degrees.

Then they move it on the the lift. I watched the fluid get drain out, no metal chunks or shavings. Then we get to looking at the assembly. It is in immaculate condition, not even a chip in any of the ring and pinion gears. Has shown no wear whatsoever after 50,000 miles.

The tech suggested maybe that grind you heard was 4WD trying to engage because there is a vacuum leak of some sorts. So then we check the vacuum on the front hubs for the 4WD. Working great.

So I left 4WP yesterday, and the vibration stopped completely. Hmmm. I have no idea where the vibration is coming from. It is obviously not a constant vibration which makes it even harder. Any Ideas?

 

man... its hard to say with out hearing it. maybe you can try and get a sound clip ? Otherwise get under your truck, make sure all the heat shields and what not aren't touching anything. If they are even close, bend em away. i know I have had them make some insanly loud noises on me, maaking me spend hours looking for what it could be, then its something as simple as that.

Oh, and glad its not your rear end!

 

I am going to get under there this weekend and make sure there is nothing touching.

I noticed a problem with 4 Wheel Drive engaging. I am going to check the front differential to see if there is any metal in the fluid.

Thanks for all the help.

 

Do you have the electronic switch for your transfer case ? or do you have the stick on the floor (manual shifter for 4x4) ? ?

Either way, the hubs up front are vacuum operated and their default position is engaged. You may have some type of problem with them, making them engage and creating a horible sounding grinding noise, and they can cause you to have problems with your 4x4. Maybe be worth checkin that out as well .

 

MecedesTech is absolutely right, we have replaced many a hubs on the new body style F150 for a grinding noise......also the solenoid on the firewall was prone to water intruision causing a very similar symptom.