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SMG "Big Boy" Drop-in Fuel Pump for 14+ Silverado/Sierra

Cab Style: Extended Cab/Crew Cab
Save 34% Save 34%
Original price $1,000.00
Original price $1,000.00 - Original price $1,000.00
Original price $1,000.00
Current price $659.99
$659.99 - $659.99
Current price $659.99

Our Exclusive "Big Boy" drop-in low side fuel pump combines a modified GM Original Equipment Style Fuel Pump Module, a High Output Walbro 535 (Hellcat ) fuel pump and upgraded wiring for a factory like fit with zero modifications required your tank, wiring, nor fuel supply lines. Simply Pull your factory Module, replace it with ours and dial in your tune for maximum results.


*Tested to support over 750whp on E85 on the this platform with stock LT4 Injectors, LT4 HPFP and 32% cam lobe. More boost, additional tuning, other supporting mods, may net greater results.



  • Bridges the gap between LT4 fueling and standalone or Axillary fuel systems.
  • Combine with one of our popular Aux Kits for Extreme fueling capacity.
  • Must-have Upgrade to increase volume and pressure beyond the popular LT4 retrofits for forced induction and e85 applications
  • Pair with a set of LT4 Injectors and the LT4 HPFP or Oversized options for the ultimate OEM+ bolt on fueling upgrade.

Fit 14+ Silverado and Sierra all trim models V8 Trucks.

**Must choose between Standard Cab or Extended and Crew Cab for proper module


*Internal test results are for R&D and illustrative purposes only and are not a guarantee of your results. Due to many variables and factors from tune, dyno, atmospheric and other conditions we cannot guarantee you will have similar results. Any "Numbers" published have been tested to and are repeatable on our test vehicle.

All Big Boy Pump Modules are made/assembled to order and tested Prior to Shipping from in stock components. Please allow 5-7 Business days from date of order being placed to when it ships from our Texas facility. Shipping speed chosen at checkout will not have any bearing on build times, just how fast it travels once done.


*BIG BOY Pumps will come with a 90 day warranty valid to the original purchaser against any manufacturer defects. This is not a warranty against lack of tuning support nor mis-installation, physical damage or damage from using unapproved fuels. If your pump is need of servicing, please contact us at with your order information.

BigBoy Notes:
  • All BigBoy Pump systems require tuning, While SMG does not offer individual tuning support, we may provide baseline settings for use within HPTuners. This information will typically be vehicle specific and if available will be included with your pump module. Note BigBoy pumps utilize OEM baskets, and FPR's.
  • Most FPRs max out at 5 bar of pressure before they will open. Pushing your pump to this limit will bleed off fuel pressure and reduce performance drastically as the pump will not be able to provide the volume needed when the FPR is dumping the excess pressure back into the tank. If you are experiencing a pressure drop from your BigBoy pump Module at high demand, its likely due to pressures rising over the FPRs threshold and it starting to bleed off pressure. Simply lowering the demand to a more reasonable pressure across the board will likely cure your issue (HPFP/LPFP systems do not need 70+ psi to run correctly, they simply need enough volume to keep the HPFP happy).
  • Commanding a flat 50-60psi tends to support even the most demanding builds due to the massive volume our pumps can push. This includes all tables where pump pressure is determined. (Be sure to address DESIRED PRESSURE Tables and MAX PRESSURE tables in your ECM and Duty Cycle tuning as well as license and tune the same FSCM Tables). Ultimate pressure needs will be determined by your car and build. 50Psi is our recommended baseline and has shown to support most high power builds, your results may vary.
  • It should also go without saying, these pumps suck.. as in they suck a ton of fuel. Its not recommended to run less than 1/4 tank of fuel when performing any sort of performance driving, as you could potentially cavatate the pump. Since its significantly more powerful than the OEM units, especially on cars with saddle tanks, the secondary side transfer is a much slower process and at low levels, the time it takes to transfer back into the pump side wont keep up with demand
  • All SMG Fueling products are designed to work with pump gas and/or Ethanol fuels only. Use of any other alternative fuel in these systems will damage seals and internal components voiding any warranty. 


Make Model Year
Chevrolet Silverado 1500 Custom 2014 - 2018
Chevrolet Silverado 1500 High Country 2014 - 2018
Chevrolet Silverado 1500 LS 2014 - 2018
Chevrolet Silverado 1500 LT 2014 - 2018
Chevrolet Silverado 1500 LTZ 2014 - 2018
Chevrolet Silverado 1500 SSV 2014 - 2018
Chevrolet Silverado 1500 WT 2014 - 2018
GMC Sierra 2014 - 2018
GMC Sierra 1500 Base 2014 - 2018
GMC Sierra 1500 Denali 2014 - 2018
GMC Sierra 1500 SLE 2014 - 2018
GMC Sierra 1500 SLT 2014 - 2018


**May Fit some early 19 chassis, confirm with your installer if you have the old style pump or the new 19+ style pumps



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