2004 Ram 2500 O2 Sensors & Exhaust Manifolds (FIXED)

I have a nice 2004 Ram 2500 5.7 120K miles on it, which I only use for towing my 24ft trailer. Are these 5.7 Hemi's prone on having bad O2 sensors. The check engine light always on. I have changed Senors a few years ago. That only worked for a short time. Is something messing up my senors. I just changed the Spark plugs today. The right bank look great maybe a little lean, the left bank are running rich. The gas mileage is down a bit also.
About 7.5 miles to the gallon with the trailer and Cuda.
Anyone have troubles with this before
Bob

What are the codes?

I know, I did not get codes yet.
Bob

Yep, Need the codes there Bob .

Or else anything is a guess

BUT, best I remember they're not known for repetitive O2 sensors failures
Did you use OEM sensors or aftermkts

Bill, actually it was done at the Dealer. So they must have been Mopar one's
I was thinking there is also a small exhaust leak on the right bank.
I do not use the trunk much.
I will get codes next week
Thanks Bob

Not uncommon for dealers to use aftermkt parts.
So dont count on they did use OE


Ps. Exhaust leak will cause o2 sensor issues

Bill, I have found out that most if not all 5.7 hemi engines have this problem with the exhaust manifolds warping and breaking the bolts. Well after looking that is exactly what's wrong with mine.Rich spark plugs on the left side and lean spark pugs on the right side where it is leaking. I am going to get new Mopar gaskets, dorman bolt kit and have the original manifolds resurfaced to correct that problem. I think this will fix all of my issues.
Thanks Bob

Broken exhaust manifold bolts on late model hemis is VERY common.
Seems to be mainly the ones towards the rear.
Probably has a lot to do with the steel manifold against the aluminum head

maybe look at using the cupped washers like on old hemi or LA small blocks ?

I probably do 2-3 5.7 broken exhaust studs a week.... if your lucky it snaps near the top instead of even with the head. I’ve been using a step drill bit to hog out the holes on the sealing side of the manifold on the end ports. I also put a generous bead of copper rtv around the end ports on the gasket. Knock on wood I haven’t had a comeback doing it this way.

I just purchased the Mopar gaskets,bolts and nuts. $250.00 with my discount.
I am going to have the old manifolds resurfaced if out of spec before putting them back on. I got the Mopar gaskets which are a few layers thick. So you enlarge the inside end holes of the manifold to release some pressure on it.
It looks like my right rear broke at the top of manifold but not sure yet.
Thank Bob

Thanks Guys and J Body.
I finally got the manifolds off. Ended up with 5 broken studs. Got one out with welding the nut onto it flush with the head. Leaving the others for another day
Bob

Most of the time you can just back them out easily. The aren't stuck in the head normally. I managed to remove mine with my fingers or a pair of pointed vise grips.

Not mine, 2004 Ram, they are rusty and tight. Even the ones that came out without breaking I needed to pull as hard as I could on the ratchet.
Thanks Bob

That's weird. The broken off bolts in the three hemis I've done (2011, 2012, 2014) have all been finger tight. The unbroken ones are hard to get loose but I think that is because they are rusted to the manifold rather than the head. Just my experience your's may be different.

We had a guy who was REALLY good with a mig welder. he would lay a nut over top of what ever was left of the stud . and 90% of them time he had them out in a few minutes

Better yet start with a flat washer. Being thinner it is easier to get penetration to the broken stud. Then weld a nut with a larger hole to the washer. The heat will transfer and help loosen the stud. Aluminum heads usually will allow easier sud removal. We always removed the inner fenders for access.

Yes that's my next step with the washer first.
Thanks Bob

Well I finally got all the broken bolts out .Let me tell you, two studs where so tight I needed to use my 1/2 breaker bar. I mig welded the washer on first then I welded a large nut onto that. This worked the best for me.
Now off to have them machined flat.
Thanks Bob

Glad it worked out. Years ago we went to the washer trick first and it worked almost without fail unless someone had previously buggerd the threads. We used to do the nut first and almost always it was 5 to 10 tries. The washer first about 50 percent or better come out on the first try.

Yes the washer first worked out way better than just the bolt welded on. With the washer you can get a better weld on the broken stud. But it takes time I still had a few welds break. No meat and a tight bolt
Bob

It's all fixed. The manifolds where pretty bad so I had my local machine shop machine them for me. Replaced the gaskets and bolts with Mopar parts, torqued them down and ran the truck. No more ticking or engine light on.
Thanks for all the help
Bob

Good to hear. A non ticking truck is a happy truck.