Engine rattling?

This sounds like the engine could be misfiring which can cause the car to rattle. Here is a guide to help confirm the problem.

https://www.2carpros.com/articles/engine-misfires-or-runs-rough

Also I would check all rubber mounts, tranny tailshaft, motor, and even body and frame mounts. Also check the exhaust system to make sure all system hangers are in tact.

Here is a guide on the engine mount.

https://www.2carpros.com/articles/replace-motor-mounts

and

https://www.2carpros.com/articles/how-a-motor-mount-works

Please let us know what you find.

Cheer

Thank you, but can I do this myself, as a novice or should I take it somewhere?

Patty, as a novice checking the mounts may be better left to a pro.

I have a 12k,12 month warranty on drivetrain only, does this fall under that category, or shall I take it to my mechanic?

Engine and tranny mounts are covered under "drivetrain".

It only does it when the car is warm,(running more than 5 or 10 min) could that be any other concern?

As you must know, the hardest type of problem to solve over the internet are "funny noises". Yes it could be something else, but if it has a 12 month warranty, let them tell you what it is and if they will cover it, tip: Dont take no for an answer!

What is a cracked flexplate? They checked all the mounts or at least said so, but I got it back yesterday and it still made the same noise.. someone said could be that and you could end up sitting if you don't get it fixed??

It sounds like it could be the starter bendix return spring is broken and hitting the flywheel. I would remove the starter and check it out.

Here is a guide

https://www.2carpros.com/articles/how-to-replace-a-starter-motor

Here is what it will be like for your car (below)

Please let us know what happens.

Cheers

No noise on startup, It ONLY happens when the car is warmed up and is accelarating or going up a hill..

Yep that is when the bendix is forced into the flywheel to make the noise becasue the spring is broken.

Ok here's the one thing I forgot. It didnt do it when it was in awd, only 2wd. Could that be a specific issue? As always, Thank You :))

I am going to suggest that you have a starter motor that has a broken return spring

Well I got it back for the 2nd time,and it is still doing it. Shifts fine, but does it up hillin 2nd gear, only in 2wd,does not do it in AWD???

if its not the starter there are two technical service bulletins on Expedition and Navigator, both for suspension problems, one is related to the compressor being too loud, and too much vibration, the other is for ride height sensor arms disengaging from the control arm on the front, or the axle on the rear, is the truck leaning to one side? or sagging in the rear?

No there is no sagging of any kind. Did notice now that the front end is out of alignment. They are having a tough time figuring it out until they removed the starter and BAM! you were right :) I am so happy thanks 2carpros!

I found this too read this entire thing, it sounds like your concern, right down to the alignment issue, This is a known problem with the lower shaft...I will email the entire TSB so you can print it and bring it with you to the repair shop. CLUNK, POP, CREAK OR TICK NOISE FROM STEERING COLUMN TECHNICAL SERVICE BULLETIN Reference Number(s): 04-26-23,  Date of Issue:   December 31, 2004 Superceded Bulletin(s): 04-16-14,  Date of Issue:   August 23, 2004 Related Ref Number(s): 04-16-14, 04-26-23 ARTICLE BEGINNING DESCRIPTION CLUNK, POP, CREAK OR TICK NOISE FROM STEERING COLUMN ISSUE Some 2003-2005 Expedition/Navigator vehicles built before 10/18/2004 may exhibit a clunk, pop, creak, or tick noise coming from the steering column. The noise may occur during acceleration, deceleration and/or while going over bumps, and is most noticeable after the vehicle is warmed up. The tick noise may occur when rapidly and repeatedly turning the steering wheel to the left or right. ACTION For a clunk, pop or creak condition, it may be necessary to replace the lower intermediate steering shaft. For a tick condition, inspect the upper-to-lower intermediate shaft union. Refer to the correct Service Procedure based on symptom. SERVICE PROCEDURE - CLUNK, POP OR CREAK 1. Road test the vehicle to verify the condition. 2. If condition is verified, replace the lower intermediate steering shaft following the service procedure in Workshop Manual Section 211-04. Torque the upper-to-lower intermediate shaft bolt to 40 lb-ft (55 N.m). FORD: 2003-2005 Expedition LINCOLN: 2003-2005 Navigator NOTE: This article supersedes TSB 04-16-14 to update the Service Procedure and affected model years. NOTE: DO NOT ATTEMPT TO ADD GREASE TO THE INTERMEDIATE SHAFT TO RESOLVE THE CONDITION. NOTE: BE SURE THE VEHICLE IS AT FULL OPERATING TEMPERATURE DURING VERIFICATION. NOTE: CHECK BUILD DATE CODES ON THE REPLACEMENT SHAFT PRIOR Page 1 of 3 CLUNK, POP, CREAK OR TICK NOISE FROM STEERING COLUMN -2004 Ford Ex...SERVICE PROCEDURE - TICK Turn steering wheel rapidly and repeatedly to the left or right while parked to verify the condition. If the condition is verified, inspect the upper-to-lower intermediate shaft union and re-torque the bolt to 40 lb-ft (55 N.m). If the noise is still present, follow normal diagnostics. PARTS INFORMATION TO INSTALLATION. ONLY INSTALL PARTS BUILT AFTER DATE CODE 0410080X (OCTOBER 8, 2004). THE LAST TWO DIGITS OF THE DATE CODE (0X) INDICATE THE SHIFT IN WHICH THE PARTS WERE BUILT (X CAN EQUAL 1, 2, OR 3).SERVICE PROCEDURE - TICK Turn steering wheel rapidly and repeatedly to the left or right while parked to verify the condition. If the condition is verified, inspect the upper-to-lower intermediate shaft union and re-torque the bolt to 40 lb-ft (55 N.m). If the noise is still present, follow normal diagnostics. PARTS INFORMATION TO INSTALLATION. ONLY INSTALL PARTS BUILT AFTER DATE CODE 0410080X (OCTOBER 8, 2004). THE LAST TWO DIGITS OF THE DATE CODE (0X) INDICATE THE SHIFT IN WHICH THE PARTS WERE BUILT (X CAN EQUAL 1, 2, OR 3).

Vibrations can travel to other sites, but this is a known problem, so lets start by checking that. Any brake work on the rear brakes yet? A severly warped rotor will be felt in the seat area.

Alright, I understand the troubleshooters suggestions, and could all be relative, but they are off. The vehicle exhibits a clatter like a torque converter failure, turbines clashing under the floor. Sometimes very loud even pounding on the floor like something is about to explode. It relates to torque and engine RPM. My expedition was (is) doing the same.
It is also an 04. Identical Symptoms. Found the blog looking for hints. I took mine to a reputable trans shop. They indicated it was definitely a torque converter. So I put in a new transmission and TC myself. Same Symptoms. Going up the Grapevine (a Hill in Cal) it grows worse and worse with the only adjustments that help is to decel. Downshift, Decel, so at second gear, at 30MPG, my car goes up the Grapevine. Did not try the AWD. A mechanic friend of mine, asked another about a similar problem with the same. He indicated it was his Transfer Case. Before I drop hundreds more, I needed a tie from the RPM to the Transfer Case. This blog saying it only does it in 2WD is my key. It is the Transfer Case or Flywheel, I glanced at the flywheel when it was apart and I saw nothing out of the ordinary.

I have same problem, it is not the Tranny-new, xfer case- new, only in 2wd, Awd fine, 4wd fine
So I leave it in auto Awd
Sounds like xfer case chain, or really bad u join, pounds under car, major failure to ensue, front axle suspect, or front diff