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I have a 99 f250 super duty with a 5.4 L triton that has started to blow spark plugs. I was wondering if it was possible to replace the engine with a diesel. If so, what would it cost and what would it take to get it done right. I've never done anything that serious to a truck and really not confident in tackling it myself. Any advice would be greatly appreciated. Thanks.
Is it possible? Yes.
Is it practical? Probably not.
Would I personally do it? Yeah, but I'm into self-punishment like that...
You're going to be getting into A LOT of work to do this swap- Wiring (if done right) is going to be a major pain. Exhaust, fuel lines, pump & filter, transmission, brackets, the list goes on and on. If you plan to go this route, you'd be best to buy a complete diesel donor vehicle of close to the same year so you have everything to swap over.
Unless the diesel swap will be a Cummins, in which you'll have even another set of things to think about. Whichever route you choose, make sure you do it right to prevent driveability issues when you're done. If you have good mechanical skills, you can do this, but if your skills are little more than changing oil and rotating tires, this probably wouldn't be a good first major project...
"I've never done anything that serious to a truck and really not confident in tackling it myself"
There ya go my friend.
I've worked beyond my skill set with humorous and life threatening results.
Thanks so much for the honesty. So if I don't go with a diesel, should I put another 5.4 in it? Or is it just going to do the same thing and start blowing spark plugs. I've put a lot of work into the truck, it's a utility body and I use it every day, all day. I'd hate to give it up
I suggest another 5.4 from the same year. Everything will be the same and it will start, run and drive. You know it will. It's yours.
Don't start out from scratch with some other scenario.
Is the engine in good shape other than the blown plug(s)? If so just get the current stripped plug holes fixed using a Timesert kit.
If you still want to swap the engine out...... I would go with a 2004 5.4l out of an F-250SD. You will pick up some more power since the new engine is a PI version. Your current 99' 5.4l is an NPI engine. PPI = Performance Improved NPI = Non Performance Improved. The 2004 will have the extra thread length for the spark plugs which will help prevent plug blow out. Some 2003 5.4l engines have the extra thread length and some don't it depends on the build date. If switching over to a PI engine you will want to get the PCM with the engine.
As far as the diesel swap goes it is usually cost prohibitive, especially if you can't do the work yourself. Putting in a used 5.9l Cummins would most likely be cheaper and easier than a used 7.3l. A gas truck does not come with a lot of things that will be needed to go to a diesel truck.
Yea the engine is in good shape. I was worried that once the plugs start to blow, they won't stop. I got the plug fixed with the insert kit, I guess I'll see how long the engine lasts and go from there. Thanks so much for all your help.
The blown out plugs are a direct result of not properly installing them in the first place. One can't simply "crank them down until they feel right" like older engines. They have to be torqued down to factory specs- which will feel "loose" compared to engines of the past. I have an early 99 with the 5.4 and over 250,000 miles. The truck has never spit out a plug nor had a thread repair done...
The blown out plugs are a direct result of not properly installing them in the first place. One can't simply "crank them down until they feel right" like older engines. They have to be torqued down to factory specs- which will feel "loose" compared to engines of the past. I have an early 99 with the 5.4 and over 250,000 miles. The truck has never spit out a plug nor had a thread repair done...
I don't torque mine and change them often but you have to know what you are doing. I would keep that engine.
Sounds to me like you all think I should keep the engine. So that's what I'll do. Hopefully the mechanic putting the insert kit in knows what he's doing. Thanks again for saving me a lot of time, hassle and most of all money. Your advice is is greatly appreciated
Just adding my two cents. I was in the exact same situation several years ago - ended up trading off a really good truck because I got scared of it after blowing out a couple of plugs. Even putting inserts in every cylinder would be cheaper than swapping motors. But if you'll do like gfl said, pull the remaining plugs and replace them, making sure they're torqued to specs, they shouldn't be any more problem.
Just install the inserts in all the holes and plug problem gone forever. I have never had any issues but I did it myself and torqued to spec. I wouldn't even consider a different engine because of the plug issue.