2004 F150 4.6L Question

Sep 19, 2003 2 Replies

Does anyone know if the spark plug blow-out problem in the 4.6's has been addressed in the 2004 engines? Also does anyone have any idea on the reliability of the 4R75 transmission in these trucks? I am in the market for a new truck and have been spoiled by the spotless reliability of my '95 Nissan Hardbody.


Thanks,



Rob Munach



AFAIK the 4.6 don't have the spark blowout problem, only the 5.4s. I also heard (on www.f150online) that in late 2003 the 5.4 heads mere modded to increase the # of threads holding the plugs.

Rob Munach wrote:

-- 'Fritz the Cat' Blackburn VP-94 Techrep NAS New Orleans

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The early 5.4L had problems with sparkplug blowout. I have never heard of that problem with the 4.6L. The problem has been addressed in the 5.4L (1999 or so and up I believe).

The 4R75 is reported to be a very reliable transmission. As with most automatics, I have heard of problems if the transmission is overheated from heavy towing and poor cooling.

Charles Perry P.E.

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