4.0 question

[rangerT]

are the 4.0 common for having bad valve guides? i haven't had my truck too long but haven't really noticed it smoking untill recently when i used synthetic fluid(full syn.mobile 1)at my last oil change. if it sits and idles for a period of time(5-10minutes)or i am just idling around and then step on it it will puff a bit of blue.if i shut it off and start it a while later i will get a puff of blue again.i am think of going back to the motorcraft oil but is this a common problem and will this also plug up the combustion chamber causing the motor to ping abit?.....truck is a 4.0 OHV with 192,000 km/h(I'm canadian eh)soooo about 120,000miles i think.....

anything helps

 

[Stranger ranger]

little puff at start up, atleast to my knowledge, usually are valve seals. On dodge 318's anyway, i know this is a completely different monster, but still.

Pinging usually indicates your MAF is dirty, or your lower intake gasket is bad or the lower intake needs tightened up a bit. There are a few other things that cause pinging but I forget what they are at this moment.

As for blowing smoke while idling, i've never see it on a 0hv 4.0 and i've been around plenty of them and with yours being relatively low mileage, (mine has 170k miles) it should not be doing that at all. Mine and probably about 90 percent of the ppl that have 4.0's on this forum I can bet don't have this issue of smoke.

 

[rangerT]

if it has been idleing for a while and then i goose it then it might puff a little but not always.....i'll check the IM bolts to make sure they are all torqued down....has anyone ever used seafoam through the vacuum line or would recommend it??

and the pinging is only sometimes not all the time

 

[Stranger ranger]

yeah i used seafoam on my ranger 4.0, as well as my jeep 4.0, the ranger had 165k and the jeep had 98k. guess which one smoked more from the seafoam.
Ha wrong, the jeep did. i barely got anything from the ranger