Hi All,

Edit:
******
Short question: is the 5.4 L 3V an interference engine and can we save the engine if timing chain breaks on city roads?

****



Need your help to determine if I can revive my 5.4L 2008 Navigator. It’s down and my family is basically very sad about it as it was our main beloved family car and cannot afford to buy a replacement with kids starting college.

I apologize for the long post but I come with hope you can help.

Let me start by saying that I am a long time reader of this forum and first time poster here.

Did regular oil changes at the dealer consistently. 223k miles on it. Did maintenance , tuneups and repair work with mostly OEM parts. ( except for suspension and body parts) Mostly put top tier gas in it. 90% of the time.

Recently, upon cold start, (Michigan cold weather) the engine started to run loud, diesel sounds and I suspected the rockers must be wearing off and maybe needed a timing job too. No check engine lights. I know it was something I should take care of. I started buying parts, but kept driving it for a week for so trying to arrange for alternate transport so that I can work on this.

on the way to pickup my alternate transport, it stopped going maybe at the most 35mph on city road. Towed it to a mechanic I know, they made some calls said they won’t be an able to work on it and could not find anyone they trust to work on it. Suggested I take it to the dealer.

Now, I am debating if I need to tow it to my home, work on it myself as I now have alternate transport and can work on this in my spare time (still need a family car). You all are experts at this, I did a lot of reading and I am okay in DIY, don’t have all the tools but can upgrade a few tools. I have watched Ford Tech Maculoco videos and I think I can do it with that resource.

Most probably I need to drop the pan to clean it , replace all timing parts , Ford OEM phasers , upgrade to milling pump , replace gaskets and possibly some cam rockers and lifters and May be the camshaft.

And timing might be totally gone, so not sure yet how to get it back and time it right.

Do you guys think my engine is toast or there is hope to fix it? I am thinking couple of grands as budget and DIY as it’s very hard to find a someone reasonable, available and get the job done right.
pls advice if there is anything I am missing, could there be more carnage as Ford tech maculoco videos talk about?

is it worth it , is there a chance this open heart surgery be successful with in the budget and with the DIY?

thanks in advance. I can provide more details if I missed out anything.