The only sound as common as a loud racecar in the paddock at any NASA event is the clattering of a diesel engine. Diesel trucks make great tow vehicles and NASA members own a lot of them.

I had the chance to get out of my 2005 GMC 1500 crew cab with a gasoline engine and into a 2005 Chevrolet 2500 crew cab diesel with less than 50,000 miles for a price that worked for me. The new-to-me truck also was bone-stock, cleaner than mine, and had more options, so the decision to buy it was easy.

Naturally, as a car guy, I can’t leave well enough alone, so I began looking at forum websites dedicated to GM diesels to find out where the trouble spots were and eliminate problems before they surfaced. My goals for any modifications to the truck are to increase longevity and improve fuel economy. I don’t need it to go faster. I have a racecar for that.

I figured exhaust would be a good place to start, so I ordered a Banks Engineering Monster exhaust system from a speed shop here in town — buy local, I always say. Banks makes a couple of different stainless-steel applications for this truck, including dual- and single-tailpipe systems with polished stainless and black chrome exhaust tips, or no tip at all. I chose the single-tailpipe system with the polished stainless tip, which cost about $500 out the door.

Banks says the system triples exhaust flow and cuts backpressure by up to 98 percent. The Banks system is 4 inches in diameter compared with the 3-inch factory exhaust, so I thought for sure it would improve fuel economy. After several trips to the racetrack with a trailer in tow — before and after the exhaust install — I can’t say I noticed an improvement in fuel economy.

Banks doesn’t advertise that the Monster system improves fuel economy, but it does say that the system lowers exhaust gas temperatures. Without an EGT gauge, I couldn’t measure exhaust temperatures, but I did notice that the coolant temperature was about 30 degrees lower when towing a trailer up the Grapevine pass in Southern California, a 4,000-foot climb and descent over the Tehachapi Mountains.

To install the system, I took the truck and the kit to Troy Martin at Full Scale Hot Rods in Ventura, Calif. In addition to building some beautiful cars, Martin owns the same kind of truck with a similar exhaust system.

The system installs in an hour or so. Don’t do it in your driveway, though. Go to a shop with a lift. Trying to pull the old system off while your truck is on jack stands or ramps wouldn’t work. You have to kind of twist and snake it out between the axle, spare tire and body and there wouldn’t be enough room with the truck on the ground or even on jack stands.

If your truck has an extended cab, it might be necessary to cut a given length off the pipe that bolts to the catalytic converter. That lets Banks offer one kit to fit a few different trucks. Because my truck is a crew cab, we didn’t need to make any cuts.

In terms of quality, the system was first rate, and everything fit well. The exhaust note changed only a little bit. It sounded a little deeper than the stock system, but it’s no louder, which is good. After racing all weekend, the last thing I want to listen to is a loud truck on the way home. All in all, I’d recommend the Banks system. Here’s how it all went together.

Modern exhaust hangers are great, but they are designed more for ease of assembly than disassembly. Spraying them with a lubricant helps you remove them.
Modern exhaust hangers are great, but they are designed more for ease of assembly than disassembly. Spraying them with a lubricant helps you remove them.
It also helps to soak the studs on the catalytic converter with penetrating lubricant.
It also helps to soak the studs on the catalytic converter with penetrating lubricant.
Even when you do soak the hangers with lubricant, you can’t take them off by hand. A little encouragement from a pry bar helps.
Even when you do soak the hangers with lubricant, you can’t take them off by hand. A little encouragement from a pry bar helps.
The factory exhaust is one piece, so after you unbolt it from the catalytic converter and remove all the rubber hangers, you have to snake it out from underneath, twisting it and lowering it to get the tailpipe around the axle, spare tire and body. It’s best to do this in a shop with a lift, not on the ground in your driveway.
The factory exhaust is one piece, so after you unbolt it from the catalytic converter and remove all the rubber hangers, you have to snake it out from underneath, twisting it and lowering it to get the tailpipe around the axle, spare tire and body. It’s best to do this in a shop with a lift, not on the ground in your driveway.
The Banks Engineering Monster exhaust system comes in five pieces. Troy Martin of Full Scale Hot Rods and Customs begins by hanging the intermediate pipe.
The Banks Engineering Monster exhaust system comes in five pieces. Troy Martin of Full Scale Hot Rods and Customs begins by hanging the intermediate pipe.
By bolting the flange to the catalytic converter, you use the forward pipe to “orient” the intermediate pipe in front of the muffler on its hangers.
By bolting the flange to the catalytic converter, you use the forward pipe to “orient” the intermediate pipe in front of the muffler on its hangers.
A little torque from an impact gun ensures the nuts stay put. Note the high-quality band clamps that come with the Banks system.
A little torque from an impact gun ensures the nuts stay put. Note the high-quality band clamps that come with the Banks system.
With the front pipes hung and bolted in place, Martin hangs the pipe that goes over the rear axle.
With the front pipes hung and bolted in place, Martin hangs the pipe that goes over the rear axle.
Martin installs the polished stainless-steel Banks muffler, which features a proprietary expansion chamber and high-temperature packing. It’s only slightly louder than stock, with a deeper tone and no drone at any speed.
Martin installs the polished stainless-steel Banks muffler, which features a proprietary expansion chamber and high-temperature packing. It’s only slightly louder than stock, with a deeper tone and no drone at any speed.
With the front of the system hung and the muffler in place, Martin hangs the tailpipe. He leaves all fasteners loose until all the pieces fit together the way he wants them.
With the front of the system hung and the muffler in place, Martin hangs the tailpipe. He leaves all fasteners loose until all the pieces fit together the way he wants them.
The tailpipe exits at the same location as stock.
The tailpipe exits at the same location as stock.
Martin hand assembles all the joints for proper fit and to ensure there are no leaks.
Martin hand assembles all the joints for proper fit and to ensure there are no leaks.
Martin installed all the hardware with the bolts facing the body. It’s a personal preference so that any stray plastic bags on the freeway won’t get hung up on any of the fasteners.
Martin installed all the hardware with the bolts facing the body. It’s a personal preference so that any stray plastic bags on the freeway won’t get hung up on any of the fasteners.
The factory system is all one piece. The pipe measures 3 inches in diameter and the muffler is not a straight-through design, which likely creates the backpressure that the 4-inch-diameter Banks system virtually eliminates.
The factory system is all one piece. The pipe measures 3 inches in diameter and the muffler is not a straight-through design, which likely creates the backpressure that the 4-inch-diameter Banks system virtually eliminates.
Here you can see size difference between the 3-inch-diameter stock catalytic converter and the 4-inch Banks system.
Here you can see size difference between the 3-inch-diameter stock catalytic converter and the 4-inch Banks system.
Finish off the system with a 5-inch polished stainless-steel exhaust tip — high and tight.
Finish off the system with a 5-inch polished stainless-steel exhaust tip — high and tight.

RESOURCES

www.bankspower.com

www.fullscalehotrods.com

Image courtesy of Brett Becker

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