Maremont Cat.Conv./new federal warranty on aftermkt.cats?

I spent the day shopping for a new OBD II cat for my '96 Classic. A very reputable independent garage quoted me $220 + $20 labor on a Maremont (Arvin) that retails (accord. to the computer I was reading over his shoulder) for $268.

Meineke quoted me "about $200 installed", also on a Maremont. I know Maremont has two grades of mufflers/cats--Red & Blue. I hope the one w/the $268 MSR is the better grade than the Meineke. Any way I can be sure? I checked the CarQuest & Maremont sites but couldn't find a parts catalog.

And re: warranty: Meineke says 25000 miles & I forgot to ask the other place before it closed, but I read the following on a May 2003 Gateway Auto Service website:

"Editor’s note: 'Also, the [federal mandated]warranty period on
aftermarket OBDII CATS has changed to a 5-year/50,000 complete
warranty (instead of the 2-year 24,000 current performance warranty).'

Jim Kemper [Editor] is an environmental protection specialist at the
Colorado Department of Public Health and Environment "

Anyone know which I should believe?

I found the answer to the newer fed-mandated warranty tho I'm not sure it's a great improvement: outer shell & end pipes are warranted 5 yrs/50,000 mi., performance warranted to 25,000 miles if car is "properly used & maintained".

If you replace the oxygen sensor (in your case, the front one) on schedule, any cat will normally last well over 100,000 miles. What kills them is a dead oxygen sensor dumping a rich mix into the engine and pouring unburned fuel down the exhaust pipe.

Hallelujah, Eagle. That is the FIRST time I've ever heard that. I've spent hundreds of hours reading forums & talking to mechanics/dealerships--hearing that this or that cat is a POS, that there wasn't necessarily a reason my cat died ("Jeeps just eat cats", several told me), that my oxygen sensors should be good for another 10000 miles, that my recent complete tuneup w/new plugs & wires should take care of the problem, etc. etc. etc.

I asked the (supposedly excellent) dealership service guy yesterday about the sensors. He said, "Well, we can test them & see"; but since he wants $550 for just the cat I knew that wasn't going to happen. The other 5 places said they had no way to test 02 sensors & seemed to think I was borrowing trouble to even mention them.

And nowhere have I ever heard that it's just the front sensor I should worry about. They're always spoken of as inseparable Siamese twins.

In view of what you've said, I'm now going to call Meineke for a price to replace cat & front sensor. Their price on the cat was the best & they have a good reputation here.

What does the rear sensor do, BTW? Are all brands of the sensors pretty much alike, too?

My Jeep dealership is an old family dealership where most of the techs actually drive jeeps, and most are friends so I can generally trust them. They sell only factory cats because if there is a problem, the factory stands behind them. If they installed an after-market cat and there was a problem, the dealership would own it. They know I run Catco aftermarket cats and they never lecture me about the rror of my ways.

On the new OBD-II systems with two O2 sensors, the forward (upstream) sensor is the one that provides feedback to the ECU to control the injector. The sensor after the cat is there to tell the OBD-II if the cat is working. I suppose it does that by comparing the data from both sensors, but that's a guess. They probably should be replaced in pairs, but not replacing the rear sensor won't affect how the engine runs. It may trigger a fault code falsely (or it might fail to trigger a code when it should).

The O2 sensors I see at Autozone are Bosch. Someone told me a long time ago that the factory O2 sensors were Bosch. I can't verify that. I buy OEM from the dealer for the peace of mind. The O2 sensor on my older XJs should be replaced every 80,000 miles. I drive multiple vehicles, so even on the daily driver that's four to five years. It isn't worth saving a couple of bucks when I amortize it over that length of time. I just checked the factory service manual for 2000 to see if they list a service interval for the O2 sensors. They don't. They tell where they are located and how to change them, but not when. Unless I see something different, I'll assume they are similar to the old ones and should be replaced at 75,000 to 80,000 miles. (75,000 is easier for me to remember, because I perform many of my services at multiples of 5,000)

You can get a nice high flow cat on ebay for $40. If you can't install it it probably wouldn't cost more than $80 to have installed. Not only would that be better, it is cheaper.

I know it, ZmOz (what does that name mean?). I can't believe some of the bargains on those auctions.

I'm a veteran eBayer; I'm just so out of my element w/auto parts that I know I'd buy the wrong one, not get some little adapter or bracket I need, not get it in time, something.

I just lectured my young-teen grandkids--male & female--on the absolute necessity of taking a course in basic auto mechanics ASAP.

PS, ZmOz et al: I'm trying to understand the benefits of high flow cats but there seems to be some controversy about them & I'd about decided they were more a "performance" thing. I read one post that said any honeycomb cat is "high flow" compared to the old pellet ones. What ARE the benefits to someone like me, & what are the brand names I should look for?

Eagle, I just saw your last post which reassures me that my cat & O2 sensors have had a good long life & I shouldn't fret about having to replace them at 90,000+ miles. I'm sure they're both original.

(Labbe's in Brunswick, BTW, has been sold to someone who no longer services autos. I think I'll just get my yellow pages & drive past every auto service shop in Bath & Brunswick til I see one w/lots of XJs parked around it & go home & bake one of my famous fudge pecan cakes for the mechanics' coffee break.)

High flow cats are a "performance" thing. But there's no reason not to have one. You will get slightly better gas mileage, and you will have slightly more HP. (about 5hp) It's not hard to buy the right one, for a '96 you need one with 2.25" inlet/outlet and an "O2 sensor bung". If you end up with one without the O2 sensor bung an exhaust shop can install one for you rather cheaply. There are absolutely no disadvantages to the high flow. I started laughing when the previous owner of my '96 told me he just spent $300 to have a new cat installed.

Is Eagle's Catco one of these? Where, besides the internet, might I be able to buy a good one at a fair price? Looking in my area Yellow Pages now I see a VIP, a Tire Warehouse, an Advance, a CarQuest, a couple of NAPAs, & a couple dozen independent ones. What--ballpark--can I expect to pay at such shops for a high-flow cat & an 02 sensor?

At a local place, a high flow is going to be more than a regular one. Online is the only place to get a good deal. If you don't want to go through ebay, you can get one from Jegs or Summit racing for about $100.