I put over 201,455 miles on my 1999 F-150 4.6L with 1 change of plugs at 120K, a serpintine belt, and 2 batterys. I thought that was pretty darn good. It still runs pretty good, but misses real bad at low speed, but will run fine once it's RPM's get up and misses going up a steep grade's. But still get's down the road.

Well I don't want to get rid of the truck, the body is cherry, the paint is still very nice and so is the interior. I want to pull a new trailer I got that weighs around 5K, So my big question is will a 5.4 L just drop in or do I have to go back to a 4.6L ? I started looking at crate motors, junk yard engines, ebay, etc. I don't want a race car just a tad more power than my old 4.6 L and not have to go through a big deal to change up to a 5.4 L.

I figured a pretty good complete overhaul of the truck well be something like this........engine 2.5K to 3.5K, rebuild the tranny 1.5K, rearend 500.00, brake's, bareings, misc. ready to run 5.5K to 6.5K, can this be done? A extra 1.5K for new paint job too if I can fit it in the budget.

Thanks for any help, I'd rather rebuild this one other than go out 35K for a new one. This has been one of the best trucks Iv'e ever owned, unbelieveable. oil changes- a few sets of tires and brakes and that is it........This was a company truck given to me by the company I worked for. I figure it deserves a fresh'en up after all the great service it has given me.

 

have you pulled the codes? that low speed miss is common with the use of wrong spark plugs in these engines. what brand did you use?

 

That was the reason I changed the plugs. The miss quit for around 15K-20Kmiles then came back little by little.

Thanks for the reply

 

did you chnage the plug boots?

 

No i didnt do that. I thought it was a fuel filter at the time. If you hit the throttel rite and floor it it will stop missing. Like I said it ran a Long time before the miss came back.
I think she's ready for a rebuild at any rate........I would bet pulling this new trailer will end it's life for sure, if not the tranny. EVERYTHING is still stock in it other than the battery .

 

well with that info i am very sure you have a bad EGR valve.

 

For that cheap a part I'll try it tell I round up all the new parts...What about a direct 4.6l to a 5.4 L swap ??
Thanks again...

 

the 5.4 will bolt up just fine but the trans and the rear end is the weak link. the 5.4 trucks come with the heavy duty trans and 9.75 rear end.

 

talking about killing the engine. My '97 has 270K on it. 3 sets of plugs and wires, 1 belt, and still running orig. upper and lower radiator hoses. Pulled a 21 foot camper for almost 300 miles with it. Didn't have any concerns about it. Got about 60 miles from home, truck started skipping real bad. pulled the codes on it, and showed a #8 misfire. after doing a comp. check, found something wrong with #8. not sure what it is yet. my point is make sure you want to spend that kind of money on your baby before you tear her down. I priced a long block for mine at $2300.