No Cats
I want to buy a '95 Ford Lightning pickup that I found on The truck is an excellent, low mileage example that'scompletely stock except for the exhaust system. It's the best example that I've found in my price range, which is why I'm willing to travel to get it. The truck is located in Michigan, where I guess they don't have emissions testing. I live in metropolitan Seattle, where they are very strict about emissions. I can't register the truck until it passes an emissions test. My question is about the missing catalytic converters. The present owner discarded them and installed a low-restriction Flowmaster dual-exhaust system. Do I have to find the original cats in order to pass emissions? Will returning the exhaust system to original specs be expensive? Thank you.
Seth Schoenfield
Seattle, Washington

Emissions regulations are getting more and more stringent. Aftermarket exhaust companies go to great lengths to make their components smog-legal. The problem is when critical parts, such as the catalytic converters, are discarded. This is an easy fix-as long as no other emission equipment was removed. An experienced muffler shop can install aftermarket replacement catalytic converters. They should be able to integrate the cats with the present Flowmaster mufflers. Get a couple price quotes. You should be able to accomplish this repair for less than 400 dollars.

Can't Bear The Noise
My '00 Chevy S-10 extended cab pickup had-and unfortunately still has-a nasty-sounding noise that appears to be coming from the rear axle area. The truck has just under 100,000 miles on the odometer. It's hard to isolate a rearend noise, but it sounded most severe on the left side, so I replaced the left rear axle bearing and seals. Apparently, I guessed wrong because the noise was still there. I was still convinced that the rear axle was the source. I replaced the right bearing and seals. The noise is still there and it's getting louder. Is there something else that could be causing the noise? Is it something that I could fix myself? I hope you can set me on the right course. Thank you.
Shawn D'ArnierGarland, Texas

If you're confident that the noise is coming from the vicinity of the rear axle, we'd suspect the inside carrier bearings. These bearings are inboard next to the rearend's centersection, but the noise can easily be transmitted outward. That could account for why you thought the outer bearings were at fault. If the noise is pretty constant (regardless of speed), the source is most likely a carrier side bearing or bearings. On the other hand, if the noise seems most noticeable on acceleration or deceleration, a bad pinion bearing could be the source of the unwanted noise. Overhauling your truck's centersection is pushing the skill levels for most do-it-yourself mechanics. It can be done at home, but special tools are required. You can rent the tools, but we'd recommend going to a professional. There's also a possibility that the noise is a result of an improper ring-and-pinion gear tooth wear pattern. You can remove the rearend cover plate, drain the gear lube (check for metal in the lube), and wipe the parts clean. Look for signs of chips, missing teeth, or unusual wear. Even if you spot something obvious, you should probably let a professional mechanic make the repairs.