Does anyone happen to know the bolt/stud size for the exhaust manifold on a 4.7?

 

i would make the guess that they are either M8x1.25 or 5/16 x 18 at varying lengths.. if replacing i would suggest GRADE 8 Hardware. and NOT the hardware from the STEALERSHIPS, as they are poorly made..

im sure someone can comfirm the size for you, as for the type/grade of hardware i always spend the extra money for 8. i feel its worth it in the long run. and if needs to be removed, run a significant less of a risk of snapping

 

Have to remove the manifold on pass side. Flange rusted through and bolt holding pipe to manifold also broke.So manifold has to come off to get the piece of bolt that broke off in manifold can be drilled out.I assuming as exhaust bolts go I will break at least 1. So trying to be prepared. Dealership wants $70 for the entire set.

 

Soak well and do this before trying to remove them tap the bolt or stud head a few times with a small hammer this just may break them lose for you the impact just may free them up.


You may want to re think that exhaust bolts are made for that purpose expansion and contraction many times they take the heat better.

Look for an aftermarket supplier for a better price.

 

im assuming that was directed at me, wich is fine. im not trying or intending on causing issue. i was only talking from experience. ive used grade 8 in diesels, wich produce a lot more heat than a gas engine. so it led to me using them on my mother's Jeep Cherokee. recently i had to replace a manifold for her, they came out no problem, and not a single one snapped.

again, my apologies if i mis-intrepreted what you meant.

 

No no not at anyone didnt mean to sound that way sorry chnaging one or two will be ok I would rather stick with what is recomended thats all.

 

Hoping to have same luck and not break them. But like to be prepared hate to start something like this and run into a issue. Agree on grade8 can get those at Lowe's a mile away. .

 

good luck getting them out. i snapped one maybe 2. i dont recall how many, but the point is that now i need a propane torch(wich i have) and a screw extractor (wich i just bought). i havent tried it yet, i will let you know. i purchased a Irwin EX-2 spiral screw extractor from Advance Auto Parts for $5.67, after Ma state tak (6.25%). it says it can extract a bolt from 5/23"-732", but 5/16 aint that far off from that.

As i havent tried it out yet, i can only imagine how it actually peforms. as soon as i use it, and figure out its performance, i will let yall know, unless someone can speak on that now. and if so, please do.. haha

 

heres moes tips. use anti-seize compound on the bolt threads, and the bottom of the bolt head. put them on, and tighten the bolt head to 70-80% of full torque, drive the truck. after 6-8 full engine heat cycles tighten to full torque. you should be ok now. this lets the manifold set in.