[Mikey1311]

I have searched a lot and sorry if it has been asked over and over.

2004 4x4 le.
Just want to make sure if I get jba lt headers and have cats made on a bpipe and the o2 Bung after the cat I shouldn't throw any codes correct? Not wanting to buy uprev or anything else like that. Bought the truck and he manifold is cracked and cats on both sides are no good. Also which hi flow cat wild be recommended. Any help is very appreciated and sorry again if this has been asked. I couldn't find it. Or I searched for the wrong thing.

 

[LaxDfns15]

You won't throw a code, but you'll want UpRev. Headers will cause you to run lean (I think) and can cause problems down the road if not corrected by UpRev.

 

[Milkc3]

This is a topic I've heard both they've ran lean, and others say they've been fine, I'm especially interested because I have the same year truck as you and looking to go the same route this summer. Hook a scanner in and check your fuel trim numbers, get a good record of them, then post header install run it for a few days so your pcm can adjust, then check your fuel trim numbers again, and post them! That'll answer your and my questions for sure.

 

[Mikey1311]

I'll probably get uprev just not till later in the year. Right now headers need replaced and I need to do emissions as well. I drive about 230 miles a month. My wife's rogue is our main family car and I have a scion as well. The truck is my toy but after summer my daily driver.

 

[04GBArmada]

I'll probably get uprev just not till later in the year. Right now headers need replaced and I need to do emissions as well. I drive about 230 miles a month. My wife's rogue is our main family car and I have a scion as well. The truck is my toy but after summer my daily driver.

I have an 04 4X4 LE (Yes it's an Armada but still...), I installed Stillen LT on a completely stock truck and drove for about 5-6 months before getting Uprev. I did however verify my AFR using my buddies Uprev cable.

Pretty much everyone says you will run super lean, but for whatever reason mine ran super rich. I was hitting 10.5-10.7 at WOT, my tail pipe was totally black and the truck was averaging like 6-7MPG (my normal is about 10MPG).

It's not recommended, but it can be done. Just check your AFR after the install and don't go around trying to race everyone.

 

[new man]

Truck will run rich if its flex fuel, lean if non flex.

 

[nightowl]

Every truck is different but the non flex typically runs lean and flex usually go rich. Either condition will cause the cats to fail prematurely just like the cracked manifolds. You need to Uprev tune no if ands or buts about it. The Cajun stage 1 fix is what you need over 2000 kits sold. I have had non flex guys ruin a engine by not tuning so beware.