Hello, I have a 1998 F-250 Light Duty with a 5.4. 218k Miles. Light knock got worse over time, especially after my last oil change. Now it is pretty bad. Mostly at startup and when the load is off the engine (when u lift the gas pedal)

I did a search here and found similar problems, mostly with 05's. My problem is slightly different as it is not a constant knock, just start up, and under decelleration. Goes away completely when you accelerate.

I have always used Motorcraft oil filter, either valvoline or castrol 10/30.

I have changed the oil weight several times, I am at 90w gear oil now. (didnt drive long,will be taking it back out)

Any help would be appreciated, Mike

 

First thing I'd do is hook up an inexpensive mechanical oil pressure gauge, and put something like 10w30 oil in. See what you have for pressure at idle, and what it goes to with a little throttle.

Second thing, it shouldn't be too hard to determine whether the knock is in the top of the engine or something in the bottom end. Top end would be pretty high pitched knock, almost a rattle. In the bottom end, rod bearings would be a pretty consistent knock, and in decreasing/increasing pattern mirroring the engine RPM's. Main bearing failure is usually a pretty deep sounding knock, partially dampened by the weight of the crank and the mass of the block itself.

Depending on the oil pressure reading you get, if you are pretty inclined, the rod bearings at least, could be changed with the engine still in the truck. In a pinch, the mains could be as well. Not the best situation, but it sounds like the engine is on the verge of maybe spinning a bearing anyway. In that case not much choice. If you do change the bearings, pay close attention to the crank journals, for scoring or evidence of overheating. Plastic Gauge is helpful to check for wear.

Dave

 

Thanks Dave, with your info, I would say it is top end.. its more like a loud tap, like piston is hitting the head. And it doesnt mirror the rpms, it does almost go away as load is applied to engine.

I replaced the motor in our expedition, twice, so I am mechanically inclined, but not real inclined to do it again. I don't even have any concrete and working in the dirt really sucks. I cant say it would be a good idea to do the bearings in this environment.

215k miles...... it's gotta have some wear. Financially I really can only afford a junkyard motor. I would like to rebuild, I am not sure w these overhead cams, the down time w machine work and the actual cost. (I dont even know at this point if the heads and block are usable) I did find a junkyard motor for 1k, they dont know how many miles are on it. I would really like to get a reman short block.

If anyone knows of a good source for reman engines, I would appreciate that info
Thanks, Mike

 

Mike

I think from your description, I'd be inclined to pull the valve covers, or cover, if you can further isolate the tapping, Could be as simple as a bad lash adjuster or defective rocker. Something "sounds" worn out. If you can fix it before it breaks, it might be pretty inexpensive.

Dave

 

You have received good advice. The 5.4 was designed to run on either 5W30 or 5W20 oil, depending on the year. I would use 5W20. The 4 and 8 rod bearings have been known to go dry ans spin, even with an adequate, thicker oil level in the pan, and damage the crankshaft. Using 90W gear oil will most certainly invite even worse trouble. In such cases, the crank doesn't get enough oil, and, if so damaged, it has to be replaced. A junkyard engine may have the same issue. When did you last change the spark plugs? Bad plugs could cause the problems you describe. I suggest you take the truck to a professional shop and have it analyzed so you know what is wrong with it. Pulling these engines requires an engine hoist and lots of time and patience. I've done it, and it took two of us two days to pull it and three days to reinstall it, but we took our time. Once the engine is out, you will need an engine stand. If you pull it, contact me or someone who has done it--before you take the engine apart. It will save you lots of time.

 

I appreciate all the advice.
Update, it is locked up. It did it at an idle in the drive as it was warming up. I will have to pull it. I have replaced the engine in our expedition, twice (may be the issue you are talking about john). I am real confident I can get it done.
I am waiting on a tax return, and I havent had work lately. I did today, but now I cant get there. I was trying to bide my time and drive it really easy, I couldnt even afford the gaskets to take it apart, unless I have the kids miss a meal.
I know I am not the only one in this economy in this situation... I will try to keep a positive attitude. Hey, at least I didnt have to tow it.
I still have the core to the last 5.4 from the 2000 expedition. I havent dissasembled it yet. It had a real deep knock, but I guess I could take a look to see what parts I might be able to use??? IDK

 

It sounds as if your torouble is the crankshaft. Pull the engine and take a look at the 4 and 8 rods on the crank on both engines. The fact that the engine locked generally means something important broke. A rebuilt long block will run about $3500 with a reuseable core or the reusable parts will be pro-rated. That approach would be the ideal solution. A junkyard engine costs about $900, and it could have the same issues. If you go to a church, someone may be able to help you if you let it be known that you need help. I've seen some wonderful things happen in that regard. You are probably facing a new crank kit in either engine you have but you should check it out first. I'd try to work with the lower mileage engine first. An engine with 218 k doesn't owe its owner much. My wife and I will pray for your situation. Good luck.

 

Thanks John! I really appreciate the prayers. I will do that, I will pull aprart the 2000 Expy motor, it has 150k on it.
I did run across a deal on a 99 f250 lariat 4x4. Brand new oversized tires, Rancho lift , (prob about 5inches) 15k miles on trans. interior is rough. 200k miles. 1300$
This truck had the engine fire caused by the cruise control harness. It is pretty toasted. I would need to use alot of parts off of mine, especially the wiring. I am concerned about the wiring and brain from mine working because mine isnt a 4x4. I am going to do some research and price the harness and brainbox before I make the purchase. Also the milage and the the windsheild are concerns.
I have to say I really like the truck. Dont want to be an idiot and make things worse and have two broke trucks.
Any thoughts?

 

The truck you describe has some serious issues, but they could be overcome. But first, any 4X4 will get considerably less mileage than a two wheel drive. Four by fours average 10 to 14 mpg at best. Would your usage justify the loss in fuel efficiency? Try placing an add on Craigslist to see if someone has a 5.4 engine sitting around in a shop or garage somewhere near you. Put an add on the bulletin board at church. You may be surprised what is out there. Is this other truck an answer to prayer? Maybe--and maybe not. My advice is pretty simple. What does three times zero equal? I just helped my son put a crank kit into his 5.4 Triton, and it was a lot of work, but it turned out well. It came in under $600 total. His engine only had 80 k of it, though. We will continue to pray for you. Good luck and god bless. J. S.

 

Thanks John, I am really going to need your prayers. I went ahead and got the truck after work last night. It took me and my friend until 3am to pick it up. I had to put my 2wd tires and rims on it to fit it on my trailer. All of my buddies are saying they want to help. I am going to start working on it tonight. I have a manual, good mind, and will power. Wish me luck!


http://i694.photobucket.com/albums/v.../F250juan2.jpg

 

I helped my son rebuild the lower end on his '01 F200 5.4 Triiton. We had trouble getting it started so we towed it to a Ford garage and they purged fuel lines. No codes. My son didn't want to give them anymore money so we went out there early the next morning to tow it home, and it started. He drove it home, and we connected the vacuum lines and plugged one that didn't appear to connect to anything. He is driving it now.

We will pray for you. Sounds as if you have lots of help. Let me know when you get it going. God bless. J.S.

 

Hows it running now John? Sending prayers back your way.

Update, Got everything burnt off the new truck, Looks good, wiring burnt but didnt burn into cpu and stopped before going into plugs on firewall. Under valve cover looks pretty clean. May not be original motor?

Off to Work on it today, hope to get alot accomplished. Still a ton to do.

Oh and the buddies I had that said they will help....LOL. Just as well, I need to do it alone so I know what came off, and where it goes. My daughter is helping, good quality time

 

Update... Got the truck to fire and run... transmission shifts good... had to get a wiring harness and distribution box from the junkyard as the 98 f250LD wont work. BTW made sure I got one that had the fix for the cruise control recall, lol.
I had to take out the entire dash and vents to get to wires up against the firewall, cutout the bad wires and spliced in new ones, all the lights and accessories work as they should now.
I have a oil filter relocation kit, last night when I had it running, a line burst... oil everywhere! Guess it has good oil pressure. I guess the fire or molten metal or plastic compromised the integrity of the lines. Going to fix them today.
I need to make sure the fuel pump is pumping right, secure all wiring and start putting it back together. Change fluids, filters, flush radiator. Windsheild coming monday. Transfering tag and insurance Mon. By tues I should be cruisin'.

 

Wow! You've been busy. It sounds as if you're a capable mechanic, electrician, and father. I hope this project works out well for you and your family. I was in the same situation you're in many years ago and now have eight grand kids. I have tried to pass some of the basic mechanical stuff on to the boys, but they show little interest Still do my own work--when possible. Take it easy on your new ride. What's important is that it gets you from point A to point B reliably. Giod bless! J. S.

 

Well the truck wasnt running, fuel pump wasnt working. I thought I got the ECU's mixed up and put the other one in. It fired up. Theft light blinking. No tach or speedo, isnt charging, wont shift past second, odometer reads -------.

Put the original one back in and odometer works, the tach works, (started it by putting fuel down the throttle body), but no fuel. Theft light flashing.

I bought the dash and the ECU out of the 99 f-150 I had been pulling parts from, from a junkyard. It does the same thing, no start.

The 98 truck cpu makes it run. IDK, might need to call a dealer to have the ECU programed?