Exhaust manifold to downpipe bolts

Reviving this old thread to add info, since a search didn't bring anything up for me. The OEM exhaust manifold to pre-cat flange bolts on my 2005 are M10-1.5x45. 15mm socket.
 
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I'll revive this old thread again, again, as I'm dropping my exhaust to do the rear main seal for a third time.

I've tried multiple different types/styles of swivels and These Sunex swivel sockets make getting to those bolts a much easier task. Even allow enough movement for me to get a Milwaukee impact up in there. They swivel very close to the head of the bolt. Pretty handy other places too.

PXL_20240501_145756448.jpg
 
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I've had to tighten mine up every 10-20k miles without a doubt.

This last time I used new OEM hardware that I had on-hand (stupid expensive to find now...) with a torque wrench to spec, rather than just driving them in using the impact... I'll see if it holds any better or any longer...

I've double nutted hardware store hardware, and they still need to get tightened again... (maybe that's from the impact stretching the bolt... I just wanted the damn thing sealed...)

To get a good hold on the bolt, swivel socket is mandatory along with 18-24" extensions. Swivel extensions also help. I found using 3/8" swivel socket (or low profile socket and 6" swivel extension) at the bolts then adapted up to 1/2" x 24" extension.
 
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FarFire70 said:
To get a good hold on the bolt, swivel socket is mandatory along with 18-24" extensions. Swivel extensions also help. I found using 3/8" swivel socket (or low profile socket and 6" swivel extension) at the bolts then adapted up to 1/2" x 24" extension.
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I used to do the extension thing, now I just reach in from the side with a ratcheting wrench.
Although, probably not torqued.
 
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LONGJP2 said:
I used to do the extension thing, now I just reach in from the side with a ratcheting wrench.
Although, probably not torqued.
Click to expand...

I've done both methods. I think after 140K I need new hardware. I get the P0298 code every 2-3mo after a longish drive. Lying on your back with wobble extensions and u joints? Or 2 clicks on the ratchet wrench while standing up getting your arm scratched up 100 clicks later. I doubt either way offers an accurate torque measurement. I snug it as tight as I can with a 3/8 ratchet and all the extension slop. Same for the flex head gear wrench.
 
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LONGJP2 said:
I used to do the extension thing, now I just reach in from the side with a ratcheting wrench.
Although, probably not torqued.
Click to expand...

Latest time, I did it while replacing the fender so it was so much easier to see what was going on.

I think the spec is something low like 35 ft/lbs so you could hit it with a wrench in your hand. I just can't imagine getting in there with a wrench and having any room to move it, good on you!
 
Since this has been revived, I'll chime in as I just did this about 3 weeks ago. I had to end up cutting my bolts off, '00 4.0. There was a gap between the pipe flange and the manifold that allowed me to get a Dremel in there, took about 3 cutting wheels to do all four bolts. I'd cut, twist, cut, twist, rinse and repeat until the bolt basically snapped in half. I then went to Ace and bought replacement hardware that would make install/removal "easier." I just did the ole extensions on the back trick with a box end on the nut, worked great with the new hardware. I'll probably back them off then tighten them back up every other oil change or so, just to keep them "fresh."
 
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Reviving this as I'm getting ready to replace my pre-cats and piping Saturday. What size Ace bolts did you use? I'm not expecting that my original hardware will come apart without breaking.
 
mjonesjr84 said:
Reviving this as I'm getting ready to replace my pre-cats and piping Saturday. What size Ace bolts did you use? I'm not expecting that my original hardware will come apart without breaking.
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Honestly not sure. Just took a chunk of cut off bolt with me and grabbed a bolt(s) that was close in diameter, and associated hardware. Before I went I but the bolt back "together" to measure the length. But pretty sure its either a 12mm or 14mm.
 
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@mjonesjr84 I recommend getting the mopar ones. I tried getting them from ace and it was almost impossible since the head is so much larger to get a bolt big enough. Once I got these mopar ones they went right in.

Here are the links and part numbers for the mopar nuts and bolts.

NUT. Exhaust Manifold. Exhaust Pipe To Manifold, Front, Rear.​

Part Number: 06506546AA

Link

SCREW. Hex Head.​

Part Number: 06505754AA

Link
 
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