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2014 GMC Sierra - More Torque For More Tow Power

Simple Bolt-Ons That Pull Their Weight

Jacob Jackson
Apr 28, 2014
Photographers: Max Matthewson
We were recently faced with a situation that most of you can relate to. While towing another truck on a double-axle trailer, we pulled out to pass a semi and once the accelerator was put to the floor, the engine revved, the trans shifted down, and then our blood pressure shot up as we hoped the engine would have enough cojones to pass the big rig in enough time. Trucks are built to tow, and manufacturers do their best to properly equip new product launches with trans coolers, heavy-duty axles, and V-8 engines with enough torque to pull the weight of the trailer. When good isn’t good enough, it’s time to look for bolt-ons that can add more torque. Yes, horsepower is the sexy number that you read about in advertisements and hear about on YouTube, but for those of us that do a lot of towing, more torque is what we really want.
The new 5.3L EcoTec3 V-8 engine found in the 2014 GMC Sierra makes 355 hp and 383 lb-ft of torque, which is a significant improvement over the last-gen 5.3L’s 315 hp and 335 lb-ft. To help the new EcoTec3 engine breathe easier and run at its peak potential, we enlisted the help of a Volant cool-air intake and Flowmaster Force II after-cat dual exhaust. More air in and more air out will improve fuel mileage and send more pound feet of torque to the rear wheels. It was a simple install, and afterwards, the truck pulled the trailer with more gusto and an authoritative roar. JBM Motoring, in Anaheim, California, handled the install while we took the pics, and their shop is equipped to lift or lower your truck, add new wheels and tires, and install aftermarket parts.

Photo 2/21   |   01.
01. The new 2014 GM trucks no longer have a plastic beauty cover over the intake manifold, so Adolfo Briseno from JBM Motoring, in Anaheim, California, started the install by using an 8mm nutdriver on the intake tube hose clamps. He could then remove the front plastic air baffle and intake tube from the throttle body and airbox.
Photo 3/21   |   02.
02. After disconnecting the MAF sensor harness, the airbox was simply given a tug and pulled free from its mounting plate. Then, a 10mm socket was used to remove the four bolts securing the plate.
Photo 4/21   |   03.
03. Out of the box, the new Volant cool-air intake (PN: 155536) includes everything needed to add more power and torque to the EcoTec3 V-8. Volant’s PowerCore dry filter uses a patented technology that provides 100,000 miles of maintenance-free filtration. Even with two pounds of dirt in the filter, it won’t become clogged and it can be cleaned with a shop vacuum.
Photo 5/21   |   04.
04. Adolfo grabbed the new Volant intake box and positioned it in place and used three of the original 10mm bolts from the mounting plate to secure it.
Photo 6/21   |   05.
05. After sliding the silicone intake tube connectors onto each end, Adolfo removed the factory MAF sensor and then transferred it onto the new Volant roto-molded intake tube.
Photo 7/21   |   06.
06. The prepped intake tube could then be positioned in between the throttle body and airbox.
Photo 8/21   |   07.
07. To keep the air intake 50-state CARB legal, Volant included these vent hoses for the valve covers.
Photo 9/21   |   08.
08. At this stage, the PowerCore dry filter was slipped in place and tightened down with the included hose clamp.
Photo 10/21   |   09.
09. Air intakes need to be enclosed to keep air inlet temps down, and Volant includes this cool-looking lid complete with a Lexan see-through panel to help keep tabs on maintenance.
Photo 11/21   |   10.
10. Moving onto the exhaust install, Adolfo placed the truck up on a lift and used WD-40 and a prybar to remove the exhaust tubing from the rubber hangers.
Photo 12/21   |   11.
11. Making things easier to remove, a Sawzall was used to cut the exhaust tubing right behind the muffler outlet.
Photo 13/21   |   12.
12. A 15mm socket was then used to remove the exhaust band clamp directly behind the flex joint. The clamp is attached to the factory pipe and was pried loose as it will be reused with the Flowmaster kit.
Photo 14/21   |   13.
13. Here’s an industry secret for you 2014 GM truck owners, from the factory the exhaust systems have a small butterfly-valve to help the exhaust rumble in V-4 mode. Flowmaster does away with that nonsense, and their complete 409 stainless steel Force II kit includes a single-inlet, dual-outlet muffler described by Flowmaster as providing a “moderate sound.”
Photo 15/21   |   14.
14. The head pipe with a built-in flex joint was bolted directly after the catalytic converter using the band clamp shown in caption 12. Adolfo then slid the Flowmaster dual-outlet muffler.
Photo 16/21   |   15.
15. Converting the exhaust to dual outlets was easy for the passenger side, as the kit reuses the factory exhaust hanger locations.
Photo 17/21   |   16.
16. On the driver side, Adolfo snaked the exhaust tubing over the axle and around the spare tire. An extension piece then slips onto the over-axle portion to extend the tubing towards the rear of the truck.
Photo 18/21   |   17.
17. Here, you can see Adolfo adding that extension piece to the passenger side.
Photo 19/21   |   18.
18. Going back to the driver side, Adolfo bolted on the new exhaust hanger and slid the rubber hanger in place.
Photo 20/21   |   19.
19. A big perk to the Flowmaster dual exhaust kit is the outlet option. Included in the kit are 90-degree elbows that allow you to route the tips behind the tire on each side or under the rear bumper on each side. We opted to mount the tips behind the tire.
Photo 21/21   |   20.
20. Here you get a snail’s view of how the Flowmaster exhaust is routed. Now we were ready to enjoy the Flowmaster rumble.


Flowmaster Inc.
Santa Rosa, CA 95401
Volant Cool Air Intake
Rancho Cucamonga, CA 91730
JBM Motoring
Orange, CA 92867



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