I have an 03 EX with a 7.3l I bought new valve cover gaskets and glowplugs would like to know if I should replace all the glowplugs or just the one that is bad? Thank you in advanced for your help!

 

I would replace them all, why open up the engine twice. Also test the new glow plugs before you install them. I have had new ones fail out of the box. Do it once do it right.

 

And I'm sure you've probably already heard, but only use Motorcraft GPs. Under no circumstances should you ever use Autolites.

 

Another vote for replacing them all, If one is bad the others could quit at any time. Also use Motorcraft, Riffraff has a great price on them.

 

Might as well replace the UVCH harness while you are in there as well. Same as above, Clay has the best prices and they are all Motorcraft. They also have built in retaining clips so no .50 mod needed but it can't hurt anyway if you choose.

 

Another Vote. Change all 8. and 50c mod
Also check torque on injectors and rocker pedistals.


You will be 75% of the way through a new cac intercooler boot change also. Order up a kit !. :0