Hey there. So Im about to buy a 98 150 4.6v8. what are the differences between the 98 and 99 models? if any. and also which motor is better within the v8's. the 4.6 or 5.4. Also does anyone know if the engines change bewtween years. mine in 98 and my moms is a 00, and i wanted to know if i could buy a tuner and tune both of our trucks. we both have the 4.6v8. thank you - Robert

 

I know that in 2001 Ford switched to PI heads on the 4.6. The 5.4 doesn't have the spark plug issue that the 4.6 is notorious about, so I myself would go with a 5.4.

There are obviously different body stylings between 98 and 99, but I'm sure you knew that.

When it comes to tuning, you can get a tuner and use the can tunes on both trucks. But they both can't be tuned at the same time. Meaning when you tune your truck, the tuner will be locked, so in order to tune your mom's, you will have to return your's to stock.

Also, if you wanted to get custom tunes for your truck, those tunes would be locked to your VIN/computer code, so you could not use them on another vehicle, even if it is the same motor.

Hope this helps.

 

4.6s never had a spark plug problem.. that was alll the 5.4 and in 2003 ish is when they went to 8 thread heads which fixed the spark plug shooting problem..

my 98 has been rock solid , not one problem and its got 137k miles.. if u have the choice though id go with an 01 or newer they do make more power due to the pi heads...

 

both 2 valve motors pop plugs if they aren't torqued in properly

the 4.6 is fine for most people

find out if the truck has had regular maintainence, fluid levels full etc

and yes you will need a seperate tuning device for both vehicles

 

lol - The 4six and 5four both had blow-out problems. - Same plug chambers in all V8 97 - 03 models mid year. The late 03's were upgraded.

Cross threading is a big problem as well. You can screw the threads up taking the plugs out, - if you don't remove them right. - Believe it or not.

The tapered plug specs are at-least a 1/2 turn, I believe their writing this on all the boxes now. This puts you @ 21+ foot lbs. Old spec is 12-16' lbs. Don't use it unless you want them jumping back out at yuh.

These heads were tested up to 100' lbs recently. New torque spec should be around 28' lbs. Like I said, careful on extracting - If done wrong, they start wrong.

Documentation can be found @ blownsparkplug.com. - guess who supports (unofficially 4 now) ?

 

Engine wise nothing for the 4.6L.
The 5.4L Hands down.
For the 4six - Not much, just security systems. The 5four is a different story.
That's been answered.

 

thank you all very much. so I should pay special attention to the plugs on my truck. i ended up gettin the truck. runs great so far. im used to the 4.2 v6. so im new to the v8s. any tips would be VERY grately appreciated.

 

Hey, don't take my post wrong - The 4six is a damn good motor. I like the 5four for it's low end. For a truck, they get great mileage IMO, - IF you keep a light foot (good luck with that lol). The smaller 4six will do most everything the 5four will do, it may have to work a little harder, but she'll work for yuh as well.

Take good care of her maintenance wise and she'll be around for along time.

 

thank you very much. do you know much about the fuel pumps on these trucks? my gas tach isnt working right it varies with wether im moving or just siting at a light!?!?!?! lol. this happend on a ranger i drove but didnt have it long enough to fix it. i went to advance and they said I would probably need a new fuel pump. lol im not really excited about dropin 196 on a truck i just bought a couple days ago. thanks again.

 

dont mean to hijack the thread, but what part of gainesville you in? I take I-75 down there all the time

 

I guess not, thought I did lol. Never heard of a "gas tach". What is it? A brand of pump?

Edit - Wait! are referring to the RPM Tach in the cluster lol.

 

I'm guessing he means his gas gauge isn't working correctly. The sending unit is on the same assembly as the fuel pump I believe. It might be corroded and need replacement or it just might need to be pulled and cleaned.

 

Really ? -Crap! I bet your right :o

Damn! -"gas tach" really thru me on that one. I don't think I've heard the SU called that before.

Oh well lol.

 

lol sorry about the typo on that. but yea, thats what i thought was the problem. what a pain. i didnt know you could take the level senor off the pump, i thought it was ones piece. i dont know much about the fuel system, so this is new to me.

 

Drop the tank and pull the whole deal out. You can replace the filter sock on these pumps as well. In fact, if you end up replacing the sender, - order a new sock (pump filter) and replace that too.

You can clean the old sock, but it's time consuming - besides the replacements are cheap. The hard part is remembering to order the damn thing lol.

Here's one from a 98 -

Filter Sock -



Sender (see the screws ? white box deal? - That's it. )




Better Pic of it-




It's fairly simple, I have the procedure. PM me if you decide to pull the pump. I'll send yuh the "How To" from Ford Service.