I have a '99 Expedition with the 5.4 that needs the right side head replaced. The head that's on there now is part number RF-XL3E-6090-C20D and is the PI "power improved" version. Local junkyard after searching for one for a couple weeks found one off a 2001 F150 5.4 and had it shipped in. I picked it up last night, and after I got home I noticed the part number is different. It has RF-2L1E-6090-C20B and is a PI head as well. Anyone know the difference between the two? Will this head work on my engine without any problems?

 

you can count the valve cover bolts to tell if they are the same (Romeo or Windsor). Other than that, the only difference possible difference if the cam (left or right) for the whole head assembly. Use your cam and your safe.

I'm not sure how many mile before a head rebuild is suggested, and maybe some else will tell by part number.

Good luck!

 

All 5.4l engines are Windsors. You should have 13 bolt valve covers. Romeo has 11.

They should be the same
the 6090 is the part description and it is the same for both.
XL3E and 2L1E are production date codes. and the last 4 digits are engineering revisions.

 

Thanks for the help. I went and looked to make sure and both do have 13 valve cover bolts. You said the last four digits are engineering revisions, do you think it will make any difference that they're not the same?

Also have one more question, my mechanic is wanting to just do this one head and not touch the other side being that I'm not having problems with it. The guys at the junkyard recommended having both removed and sent to the machine shop to be cleaned up and a valve grind done on them both to make sure they perform equally. It would obviously be less expensive both in parts and labor to do just one side, but I don't want the truck to run badly by not doing them both. What should I do?

 

How many miles are on it? If 100k or more, I would pull it just to be safe.
I wouldn't worry about the engineering revision. Subtle changes that have spanned over a few years.

 

It has about 215,000 miles on it.

 

I would do both heads. I'm sure the valve springs are getting a bit weak and a vavle job wouldn't hurt. It's just better to have both heads about equal.

 

I understand about the valve job, but what are you saying should be done with the springs? Are you saying they should be tested to see if they're still ok, or that they should all be replaced?

I appreciate all your help.

 

If it were me with a 215K motor doing heads, I would definately replace valve springs and all hardware during the refresh.

 

Personally, I would replace them while having the valve job done on the original head just to be safe and put the rest of the new set on the new head.