So, I have an 06 SLT non-hemi, V8 Durango. Overall, it has been great and the family loves it. We have a big family so it works well as the family traveler.

Currently has ~150k on it, no real major repairs needed. Not driven that much other than my wife taking my daughter and picking her up from school each day.

We bought is used about 4 years ago for a great price. There is one thing that I have noticed from the beginning and it has started to bug me now and I can't quite put my finger on it. I now think it might be clogged/block CAT.

I will try to explain it best I can.

I will say it happens more noticeably when cold (engine temp, not ambient temp).

It seems as though it is lacking power from start until it gets warmer. This is is every gear mainly. If I floor it, the engine speed increases, but it just feels like it doesn't have any get up and go, if you know what I mean.

Then, and this happens all the time, say I am driving along at 55 mph on the highway, and the grade increases. Clearly the RPMs start to lower and I start up the hill, then just before it drops down to the lower gear to increase power, I can feel a stutter in the power. If I kept the gas pedal pushed in the same amount, it lasts a long time. Usually, and this always fixes it, I just press the gas in further and it drops down a gear as it should and when I get to the top of the hill, the gear shifts up like it should and it is smooth.

Transmission always shifts smoothly, no noises even when this power drop happens, engine sounds great. It is just this clearly obvious drop and stutter in power.

I will say that I have had to replace the Bank 2 Sensor 2 O2 sensor about 3 times now since I have owned this vehicle. Always comes up as a high voltage fault. This is on the passenger side cat.

Does this sound like the CAT? If not, what else could be causing this? I don't feel it is a transmission issue because it has always seemed strong and there is nothing about the symptoms that lead me in that direction. It is just a weird power issue.

One final thing - I am 90% sure that I have the CA emissions package, which sucks since I don't need it as I live in VA.

I haven't looked around a lot, but on Rock Auto, they only have CAT's that specifically say something to the effect of it is illegal or should not be used. I understand why, if you live in CA, but I don't. So the question is - CAN I use it - meaning, will it work and they are just warning me of the legality or what?

 

You can remove the front 02 sensor(s) and take it for a drive, if it runs better, then, yes, it points to a cogged cat.

 

You mean the 2 between the manifold and the cat, not the ones after the cat, right? Other than it being a pain in the a%* to remove those that does sound like a great idea. I will know almost immediately I think. Might have to pay my mechanic a few bucks to help me out with taking them out...I have tried and without a lift it is hard to do.

 

Yes, the ones in front. Gives the exhaust gasses another place to go if the cat is clogged. It will throw the check engine light on, but you can clear that.

 

I know this post is quite a few months old, but I hadn't ever gotten the chance to check this out. I missed your post with the video (love that guy btw - all his stuff is awesome). He mentioned getting a muffler shop to weld on a universal cat. Sounds like a good idea to me, but was curious - are there any downfalls to doing this on my truck? Based on some symptoms I know AT LEAST one has got to be clogged. I imagine the muffler shop could do the testing as well. I suppose I will at least see what they would charge me. If a decent price, I may do it anyway, even if they aren't totally clogged just so i will know they are new.

Mike

 

Of course, muffler shop should be able to diagnose a clogged cat.