Alright guys. Truck is a 5.4L with 196K.

I've been having a problem with coolant filling spark plug wells on the driver side, specifically plugs 6 and 7. I suspected the intake manifold gasket, but when I inspected it further, I noticed that there was traces of coolant ABOVE where the manifold mates to the engine.

Has my intake manifold failed?

The truck only seems to lose coolant when the engine has cooled off.

 

I'm no expert but have you checked the water pump?

 

I have.

The water pump is a bit too far away to cause the problems I described.

 

By a new Dorman intake from ebay and replace it, Dorman intake is better than OEM from Ford and cheaper. Ford intakes crack at the corners causing antifreeze leaks up top and in the valley of the motor. Don't try to tighten it, it will make the leak worst! The plastic is breaking apart from the heat over the years. The new one will out last the truck! Comes w/ built in gaskets/seals. hope this helps ya.

 

Pressure tester for the cooling system and see where the leaks are coming from. Do it on a COLD engine. Should be able to use one from Autozone or Advanced auto parts. Pay for it and then return it for your money back. That is how they lend tools to you. Ask first! Sorry, should have told you this first!

 

Thanks! I actually ran a pressure test yesterday. Looks like there's a small crack where the aluminum crossover mates to the plastic.

I ordered a Dorman 615-188, and it should be here tomorrow. Guess I'll document the install. lol

 

Well, the intake is in. No leaks yet.

The Dorman unit is pretty unique compared to the OEM manifold. The PCV is a separate elbow, the gaskets are integrated into the assembly, and Dorman opted to use self-tapping plastic screws instead of inserts (not a big fan of that.) Also, I noticed that there is no plastic stop that keeps the COP from rotating as you tighten their mounting screw.

My truck had a NVH cover with the original manifold that will no longer fit due to the Dorman manifold's different shape. Without that cover installed, you can peer pretty easily into the engine valley to see if the heater tube leaks.

The truck runs and sounds the same, however. I liked that the kit came with extra screws and a thermostat. I was hoping that maybe the truck would feel faster, but alas... it's just as slow as it's always been. lol

 

So let me ask you, if you had to do the job all over again, would have used the Dorman or an Ford OEM manifold? I like the Dorman myself. I have used Dorman products for years. For window motor/trans repairs, FPDM, etc... Never had a customer complaint. I always look at Dorman first to see if they improved on what I am replacing. Most of the time it is an improved part over the OEM part and cost less.

 

If I had to do the job over, I'd use the Dorman again.

Of course, I'm an advocate for Ford/Motorcraft wherever possible, but the only Ford intake manifold I could source online was at Tasca or eBay, and those were around $360 vs $170 for the Dorman.

Usually, with parts like alternators or water pumps, I notice that they just run rougher/noisier than the OEM stuff, but the lifetime warranty on these parts usually sucks me in.

In this case, the intake manifold has no moving parts, and while there were some things I didn't like about the design, it matches OEM fit and function.

The part I would buy If I had to do it again would really depend on how much spare cash I had, and if the original product had a design flaw. I almost got 200K out of the OEM manifold, so the "improvements" of the Dorman intake don't mean as much. I only bought it because I was poor. lol

 

I put a Dorman intake in my truck about 2.5 years ago, at 105K mi. I'm at 135K and my truck is leaking coolant again. I've been working all week, tomorrow is my day off so I haven't had time to go in and really find the leak. But it looks like the crossover tube area. I'll know more tomorrow.

But I said when I did this intake that if it happened again I'd use the aluminum intake from an expi so I didn't play with this plastic bullshhhhhh..
Has anyone done this? I know the expi's had two different intakes. One put the TB in the back over cylinders 4&8, the other is in the same location as ours. I don't know, but I was hoping someone had used one and could confirm they are the same. Or not.

 

So the leak originates from the cross over tube, and only seams to leak after being driven and shut off, not leaking while driven.

But all weekend has passed, and no one has chimed in whether or not an intake from an expi is able to be swapped in??

Aluminum far exceeds the limits of plastic. I am contemplating an aluminum intake, port matched to a ford factory intake gasket. Any feed back on this idea?

 

You should probably just stick with a plastic one. They're smoother on the inside, so they probably flow air better as well.

I would imagine the torque sequence is important for the longevity of these intakes.

 

I have never seen a difference in the 5.4 aluminum manifolds between the Expedition and the F150. I have had 3 Expeditions with a 5.4. All of them had aluminum intake manifolds and all of them had the throttle body in the same location as my 99 F150 - when it had a V8. There were some slight variations in heater hose location and vacuum ports, but in my experience (could be wrong) any aluminum intake will bolt on as long as it's from a PI 5.4. I have never had a plastic intake 5.4, so I don't know what other modifications may be required.

 

Smooth/rough not an issue. I would port match it to the head and/or intake gasket. I can smooth out any rough casting. Truth spelling is, it's not a high performance motor, and some turbulence helps spread the air/fuel mixture. I want something that can take the pressures of towing and steep grades. I commonly enough see long 9% grades.

Well, I think I'm going to take it on. As for heater core hoses, I could stand to replace them, and I have a custom hose shop here that can build anything. So I'm not too worried about a little fabrication.

 

^^^Take lots of pics and let us know what you had to change to make it work. I am not a fan of plastic intakes either so if there was another option that is not too much of a hassle I would be interested.