Using 04 heads (18mm) on an 06 truck (20mm)

[Mdub707]

To convert to the smaller dowel heads you will need to get the t-40 headed injector hold downs. The t-45 headed hold downs will NOT fit in those small dowel heads. The dowel locations and bolt sizes for the rocker carriers are also different between the early and late production motors.

Thought about this more, assuming I have the 18mm heads... one head was replaced under warranty with a 20mm head (assumption)... Would they have used the T-40 hold downs then in the 20mm head? Are they even interchangeable?

 

[SIX_OHH]

Uh when do you get the truck back to do the work? Your just gonna have to learn this one.

 

[Mdub707]

I have the truck back, had it for a couple weeks now. It's bleeding pressure off almost non stop through the cap. It needs to be torn down ASAP. I'm trying to order all of the parts BEFORE I tear into it, I'd like to have the least amount of down time possible, due to this job being done on a buddies lift, and he does use the lift to make money during the week. The longer it sits on his lift, the more money he's losing. He isn't going to care if we run into an issue, but I'd rather get as much done up front as possible. Plus that is less time I have to worry about borrowing another vehicle from someone.

I'm sure someone who knows what they're talking about will be along to reply.

 

[SIX_OHH]

If you really want an answer then ask shawn or matt. Maybe steve. One of them would know

 

[PSM_Kid]

Thought about this more, assuming I have the 18mm heads... one head was replaced under warranty with a 20mm head (assumption)... Would they have used the T-40 hold downs then in the 20mm head? Are they even interchangeable?

Whenever you get a reman head from ford you must specify which heads are coming off the truck. All ford reman heads have the 20mm dowels. The reason why you specify is so your hold downs/rocker carriers will work. Therefore it should have the 20mm dowels. No, they are not interchangeable without matching head/hold down/rocker carrier.

 

[Mdub707]

Ok, I've got a full set of injector hold downs for 18mm heads in a box I can use though. Anything else that wont work?

 

[Craig@MFI]

The rocker box wont work if your going from 18 to 20 mm the dowels are different in the rocker boxes

 

[Mdub707]

I believe there is an extra set of those kicking around too, guess I'll have to make sure on that one. Thanks for the input guys.

 

[Mdub707]

Ok, 18mm gaskets are in! My buddy has his 18mm heads I'm going to be using, he has spare rocker boxes and spare injector hold downs so I should be good on that front. Just going to play it by ear as we go.

All that is left is ordering oil cooler, STC fitting, stand pipes/dummy plugs, and a few other odds and ends like exhaust manifold gaskets and what not. Already have the ARP's here and a slew of other things that need to go on. Cab should be coming off in the next few weeks I hope. Gonna start with coolant flushes with the restore and take it from there. Also may try to make my own modified intake manifold. We'll see how that goes.