As some of you may have read on a thread I started last week, I am thinking of buying a 2004 scab, 5.4 4x4 but it was making some noises. https://www.f150online.com/forums/20...e-problem.html

Well, I'm pretty sure I figured it out. I was actually driving it back to the owners house to give it back to him. I was driving along at 60 mph and there was a loud bang and I started slowing down even with the engine revving. I put it in neutral and coasted to a stop. While doing this the truck stalled.

Once it stopped I put it in park and tried to start it with no success, the starter would spin and sounded like it was engaging the starter gear. A guy stopped to see if I needed a hand, so I asked him to look if the engine turned over when I hit the key and he said it wasn't.

I crawled underneath, popped the plug from the bellhousing and was able to turn the torque convertor with my finger. I think that the only thing it could possibly be would be that the flexplate was cracking around the crank and finally let loose.

If you read the other post, I'm pretty sure that if this is the problem it would explain all the other noises. Does anyone have any suggestions on what to check or what else to look for?

 

I would shy away from the purchase unless you are getting a hell of a deal. Its going to nickle and dime you at 130,000 miles if the previous owner ran the **** out of it.

 

He definitely didn't run the **** out of it. It was his daily driver for a 40-100 mile round trip commute and he's not a mad man driver. 4wd was really only used on snow and ice covered roads.

I plan on pulling the engine instead of the transmission to replace the flexplate. While the engine is out I will change the plugs, check the timing chain and other parts, and replace anything else that needs it or is suspicious. I imagine that a bit of preventative maintenance at the start will fend off most of the nickel and diming.

 

You could have sheared the bolts that held the flex plate on. I think that counts as a new way to break one of these trucks.

 

One other thing I forgot to mention. When I popped out the inspection plug on the bottom of the bell housing there was shavings of metal that reminded me of clean steel wool. It's dry in there so I'm guessing right now that they are shavings from where the two parts of the flexplate were rubbing after it broke.

 

Well, to be honest, it's all conjecture until you drop the tranny/pull the engine to verify. It wouldn't surprise me if there were a small amount fine metal shavings in that location. I wouldn't even go about ordering parts until you open it up and see what you are working with.

 

This would be the second flex plate I've heard of breaking. Not good.

 

If the convertor fell forward in the hole it can tear up the convertor and the input shaft on the transmission

 

I was able to get it up on jack stands today and pull the inspection cover off the bell housing. While turning the torque converter and flexplate by hand through the hole on the bottom, I could see the center of the flexplate still attached to the crankshaft and the outer piece still attached to the torque convertor. It's hard to see clearly, but you can just see some of the jagged edges of the two pieces of the flexplate.

I really don't think the torque converter has moved at all because the starter still engaged the ring gear when I first tried to start it back up and from what I can tell it still looks to be in the right place.

 

if you do get this truck and pull the engine and it is the 5.4 3v you might want to go ahead and pull the front timing cover off and check your timing chain guides and tensioners, may want to go ahead and replace them and cam phasers.

 

Just had the flexplate in my truck break towards the end of February. If I remember correctly it cost somewhere around $250 for a new flex plate,tranny lines, input shaft seal, new gasket that goes between the transmission/transfer case and 16qts of transmission fluid. My converter was tore up a little bit but I filed it down and it's been fine the last 3 months.

 

I was planning on doing that already. After reading up on the spark plug and timing system issues I'd be crazy not to address those things while the engine's sitting on a stand.


Thanks for the info! Did the jagged edges of the flexplate dig into the torque converter and that's why you had to file it down? Which torque converter did you buy? I'm only finding two aftermarket ones, Pioneer and ATP.

 

Ya, the flex plate dug into the converter. I think it happened after I had it towed home. I tried starting it to try to figure out what was wrong with it and when I started it up it revved to about 3000 RPMs and it sounded like the world was coming to an end. I'm thinking that was the flex plate bouncing around in the bell housing I tried starting it again and the starter just spun. It sounds like ours broke about the same. The center of the flex plate on mine was still bolted to the crank shaft, the rest of it however wasn't.

I didn't buy a new torque convertor, I reused the one I had. It was replaced at some point though because it wasn't the factory converter.

 

Oops! I meant to ask you what brand flex plate.

 

I went with the ATP.