ARP 129-2503 Balancer Bolt Kit (2001-2023 Duramax)
Fits: Chevrolet • GMC
Diesel Dollars is Southern Diesel Supply's Loyalty Program. Purchasing with Us Earns you 1 Point for every 1 Dollar spent to use for future buys!
By ordering the ARP 129-2503 Balancer Bolt Kit (2001-2023 Duramax) you will earn 31 DIESEL DOLLARS in your SDS Fuel Tank!
The ARP 129-2503 Balancer Bolt Kit replaces the factory harmonic balancer bolt hardware on 2001-2023 6.6L Duramax engines, LB7 through L5P, in Chevrolet Silverado and GMC Sierra heavy-duty pickups. You buy it for one reason: Pro Series balancer bolts rated at 200,000 psi tensile strength, designed by ARP to exceed the OEM fasteners in strength and durability.
Fitment
Listed for 2001-2023 Chevrolet Silverado and GMC Sierra 2500HD and 3500HD pickups with the 6.6L Duramax. That covers every 6.6L generation in that span: LB7 (2001-2004), LLY (2004.5-2005), LBZ (2006-2007), LMM (2007.5-2010), LML (2011-2016) and L5P (2017 on). On 2001-2004 trucks the one-ton was badged 3500 rather than 3500HD; the engine and the fitment are the same. The listing runs through the 2023 model year, so if you have a 2024 or newer L5P, verify fitment by VIN or call us before you order.
Why this part
The balancer bolt is what clamps the harmonic balancer to the front of the crankshaft. It is not a fastener you want to wonder about. ARP built this kit around its Pro Series balancer bolts, rated at 200,000 psi tensile strength and designed to exceed the OEM fasteners in strength and durability. ARP sums up its Pro Series balancer bolt kits in three points: optimum design, enhanced reliability and increased strength.
The strength comes from how the bolts are made. ARP cold forges each bolt to keep the molecular integrity of the steel, then heat treats it before the threads are rolled and the bolt is machined. If the balancer is already coming off for a front seal or other front-of-engine work, that is the time to put a stronger bolt back in.
What you get
- ARP Pro Series balancer bolts, rated at 200,000 psi tensile strength
- 8740 parallel ground washers
Specifications
- Increased Strength
- Increased Reliability
- 200,000 Tensile Strength
ARP part number 129-2503. Bolts are cold forged and heat treated prior to thread rolling and machining. Washers are 8740, parallel ground.
About ARP
ARP, short for Automotive Racing Products, was founded in 1968 and is based in Ventura, California. It makes high-strength engine fasteners for racing and performance engines, and on diesel trucks it is best known for Duramax and Cummins head studs. Its Duramax line also includes valve cover bolt kits and chromoly bolts.
Frequently asked questions
Will this fit my 2015 Duramax?
Yes. The kit is listed for every 6.6L Duramax from 2001 through 2023, and that includes the 2011-2016 LML. If you are not sure which engine your truck has, send us the VIN and we will confirm it.
What makes it stronger than the stock bolt?
Material and process. The Pro Series bolts are rated at 200,000 psi tensile strength, cold forged, and heat treated before the threads are rolled and the bolt is machined. ARP designed them to exceed the OEM fasteners in strength and durability.
Are washers included?
Yes. The kit includes 8740 parallel ground washers along with the balancer bolts.
Questions on fitment? Call the shop at the number in the header. We install everything we sell.
Diesel Dollars is Southern Diesel Supply's Loyalty Program. Purchasing with Us Earns you 1 Point for every 1 Dollar spent to use for future buys!
By ordering the ARP 129-2503 Balancer Bolt Kit (2001-2023 Duramax) you will earn 31 DIESEL DOLLARS in your SDS Fuel Tank!