So, after nearly 2 years of dealing with performance and fuel economy issues I am happy to report that my girl is finally recovering.

Right off the bat I'll say that I'm embarrassed that I missed such an obvious issue for so long. Moral of the story...don't be lazy and don't be in a rush.

Earlier this year the truck one day started having dangerous levels (in my opinion) of pining with anything less than premium. This went on for a few months and after running out of ideas... I fellow car guy at work said "the car is 23 years old, it's most likely the issue. Turns out it was generating excessive heat. This was 6-7 months ago.

A month or so later I had the car swapped with a magnaflow OEM fit. I started to do the swap myself but struggled with the bolts and my health issues... Now, here is where I messed up... With the excitement of finally being done with this issue, I just picked a random shop on a Saturday to do the swap. This was the first mistake, I was in a rush and should have waited to use a mechanic I trust.

When I first started the truck, she was louder but I chalked this up to it being a $650 cat vs an OEM $3000 one. Second mistake...BUT, this did improve the milage (from 17 to 19) for a few weeks at first so it gave me the false impression that things were fixed. From this point, the truck slowly went back to having issues, though the pinging was totally fixed. Mileage was all over the place, 16/17 where prior to these issues I had gotten her up to 19/19.5 on my regular weekly commute. Power just dropped off and she would just bog all the time...

After admitting defeat, I went to my trusted mechanic. Upon hearing the truck and smelling it, he instantly said "exhaust leak man". He did a smoke test and found TWO issues.

1.) The new cat was defective; the flange was slightly bent/warped so there was no way for it to mount flush.

2.) The shop that did the swap ruined all of the studs and never told me.

So, after he tried to man handle the broken studs out, he sent me to a muffler shop down the road owned by a buddy of his. His guys tried the welded nut trick for about 5 minutes and then apparently said "f this". Told me they busted out the acetylene torch and just melted those suckers out. New bolts went in, along with a new warranty replaced cat.

As soon as I left I could tell that the ecu was "relearning" as the truck drove oddly for about 5 miles, but even then I could tell it was improving. 30 miles later and she's running better than I can ever remember! No more hesitation! Plenty of power; pulls strong again! It's easy to spin a back tire if I punch it turning into the highway. I went from hating to drive my rig to loving it again. Sure they are not "fast", but they are not weak either!

I'll need to do a few tanks to see if mileage improves but I'm confident it will be better.

TL;DR

Don't be lazy like me, do shit the right way the first time...

Thanks for posting. I have to replace my 5 year old after market exhaust my gas milage is suffering as well. Have to install a Walker SS cat back one of these days.

Does walker make a SS oem fit or does it require cutting/welding? I've been told the magnaflow probably won't last for a long time so I'll have to keep a backup in mind...

Is yours restrictive or leaking?

I replaced both of my OEMs with Walker direct-fit in 2015 and so far so good, the exhaust piping is not stainless. They did fit without any mods but I'm not a fan of the crush bend at the main inlet, I heard Magnaflow uses mandrel bends, at least on pics of a 4th-gen 4Runner V8.

Interesting. I will say that visually the mangaflow direct fit cat looks like it is made well. Good bends and welds, but I'm not an expert.... Haha

I wish someone made a stainless tail pipe for our rigs. Mine looks like trash.

Northeastern Stainless has them for around $90 on Amazon

Really? I'm searching that right now

I’m sure they’re available on Amazon as well but quick search turns this up on eBay.
https://www.ebay.com/itm/19261373388...mis&media=COPY

Same company/seller but that's the complete exhaust, from what jross20 said I'm assuming he wants just the tailpipe. When I was exhaust shopping for my Tundra, their Amazon store had the best deal and quickest shipping.

It fits but some times the hangers have to be bent to fit the isolators. I had an after market muffler installed about 6 years ago at a muffler shop that has rust pin wholes and inside baffle rattle.

Actually my first choice would be going with an OEM muffler/tailpipe if I could find a new one for reasonable price or even nice used one in good condition.

The northern stainless exhaust you can just buy the tailpipe, and it will bolt right up. Well, it did for me on a walker muffler that rotted up a year later....

Sent from my SM-A536V using Tapatalk

Same here, the outlet of my Walker muffler (and most of the OEM tailpipe's flange) rotted away

So I have an update; to my shock some of the pinging has returned but it's very rare and tame... I'm wondering if this is just the normal pinging that the manual mentions?

Thanks for sharing! I dread the day my cat goes out!