Any tips on replacing exhaust manifolds?

I have worked on vehicles before but do not have much Ram specific experience. I am talking about a 2004 Ram 2500 4wd with the 5.7 Hemi that we use at work and to tow Jeeps sometimes.

The motor and Trans were overheated and badly damaged by an employee, It was overworked on a job while our dump tuck was getting the motor rebuilt. It was a costly mistake and it now has a new motor and trans in it. The shop also had to take it back and redo it a second time because the new motor overheated as well.

About a week after we got it back again it developed an exhaust leak or leak at the manifolds that is pretty significant. The shop says the manifolds are warped and want way too much to replace them. It runs great otherwise so we ordered new manifolds, gaskets and bolts on our own.

We are going to do it ourselves, do you guys have any tips or specific approach or torque specs you need to do the job of swapping in new manifolds properly? It was all recently apart so hopefully we aren't dealing with broken bolts, but I will still do some Pb blaster soaks on the bolts.

I found this video that seemed like it would be very helpful to use as a rough guide but it is a Dakota and I am not sure how different the Ram layout would be. I was not able to find any clear walkthroughs or videos with a Ram in them but I am hoping I can go in through the fender and it will be built similarly.
https://www.youtube.com/watch?v=bQYpCJ6OmS4

Anyway t.i.a. for any insight you can share, like if I may need to get an odd sized socket or torx or inverted torx type crap I find myself needing on my Jeeps.

take the wheels and wheel wells off to get the best accessibility.
i would soak it in PB blaster everyday for 3 days before doing the install.
buy new bolts and get grade 8 bolts.
a week after you install the manifold, re tighten the bolts.

by the way, i have the manifolds if you haven't ordered them. just i am not sure if they are the same for the 1500. truck had about 70k miles on it before i took them off.

05singlecabHEMI said:

take the wheels and wheel wells off to get the best accessibility.
i would soak it in PB blaster everyday for 3 days before doing the install.
buy new bolts and get grade 8 bolts.
a week after you install the manifold, re tighten the bolts.

by the way, i have the manifolds if you haven't ordered them. just i am not sure if they are the same for the 1500. truck had about 70k miles on it before i took them off.

Click to expand...

I already ordered them but I believed they would have worked.

We figured out that the bolts connecting the manifold to the exhaust were loose so we replaced them but that wasn't enough so we will go back in this weekend and swap in the new parts.

Thanks for the input!

My guess is the manifold gaskets are burned out. I would use only OEM manifold gaskets. You may also find a few manifold bolts broken. And I expect the manifolds are fine.

Thanks for the Tip we did get the Mopar seals/manifold bolt replacement kit. Hopefully we don't regret buying the cheap ebay manifolds but it is what we can afford atm.

I don't want to waste the new gasket and find they were right about the old ones being warped so I think we will swap in the new ones.

We are going to try and knock it out today and hopefully that is it. I need this thing back up to par, I have a new Jeep to pick up a few states over!

We got it knocked out and there are no more leaks!

We had a little trouble because I thought the bags of the new hardware were one for left and one for right. The longer 8 with the threaded studs to mount th heat shield go on the outside for corners of either manifold.

We did not know that since it looks like the shop that did the motor did not reattach the heat shields. This was likely because they used random bolts that weren't even the right size. After figuring all that out it all went together rather smoothly.

Another thing we noticed was whatever brand gasket they used was very crappy and thin with way less layers than the nice Mopar one we used.

Redtruck-VA called it the manifolds weren't even bad but we decided to swap in the new ones and sell the old rusty ones.

Now I am wondering if the heat shield being gone is going to cause any issues. I am thinking it will be ok but I am sure it was there for a reason.

OutkastBoss said:

We got it knocked out and there are no more leaks!

We had a little trouble because I thought the bags of the new hardware were one for left and one for right. The longer 8 with the threaded studs to mount th heat shield go on the outside for corners of either manifold.

We did not know that since it looks like the shop that did the motor did not reattach the heat shields. This was likely because they used random bolts that weren't even the right size. After figuring all that out it all went together rather smoothly.

Another thing we noticed was whatever brand gasket they used was very crappy and thin with way less layers than the nice Mopar one we used.

Redtruck-VA called it the manifolds weren't even bad but we decided to swap in the new ones and sell the old rusty ones.

Now I am wondering if the heat shield being gone is going to cause any issues. I am thinking it will be ok but I am sure it was there for a reason.

Click to expand...

Good, you got her done... Many of us especially all of us with aftermarket headers don't use the heat shields without issues. I actually cut mine up and used them to shield some wires near the collectors.