The Story
ARP Pro Series Main Stud Kit
For Dodge Ram 5.9L Cummins with Main Girdle (12V & 24V)
When pushing a 5.9L Cummins to extreme horsepower levels, the weak point isn't just the bolts—it’s the block itself. To prevent the main caps from walking and the block from flexing, many high-performance builders utilize a main girdle. The ARP 247-5401 kit is specifically engineered with the extra length required to accommodate a main girdle while providing the legendary clamping force of ARP hardware.
This kit is compatible with both the 12-valve and 24-valve 5.9L platforms (1989–2007) that have been equipped with an aftermarket 12mm or 14mm thick main girdle.
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Key Features & Benefits
-
Extended Length Design: These studs are specifically longer than standard main studs to account for the thickness of a main strengthening girdle, ensuring full thread engagement and proper nut seating.
-
Premium 8740 Chrome Moly: Heat-treated in-house to a tensile strength of 200,000 psi, providing a massive upgrade in strength and fatigue life over factory bolts.
-
Superior Bottom-End Rigidity: By tying the main caps together with a girdle and ARP studs, you virtually eliminate "main cap walk" and block distortion, which is critical for engines exceeding 800+ HP.
-
Consistent Clamping Force: Studs provide more accurate torque loading than bolts because they do not "twist" into the block. This ensures that the main bearing bores remain perfectly aligned under extreme stress.
-
Black Oxide Finish: Precision machined and finished with a durable black oxide coating for maximum corrosion resistance and long-term reliability.
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Why Use Girdle-Length Studs?
If you try to use standard main studs with a girdle, you will not have enough thread for the nut to fully engage, leading to a catastrophic failure of the bottom end. The ARP 247-5401 kit solves this by providing the specific reach needed to secure both the main caps and the girdle to the block webbing.
In high-boost applications, the crankshaft exerts massive oscillating forces. This kit ensures that the entire bottom end of your Cummins acts as a single, rigid unit, protecting your bearings and crankshaft from the "fretting" that destroys high-performance engines.
Important Installation Note: Installation of a main girdle and studs requires the block to be line-honed by a professional machinist. The increased clamping force and the addition of the girdle will change the roundness of the main bearing bores.
Description
ARP Pro Series Main Stud Kit
For Dodge Ram 5.9L Cummins with Main Girdle (12V & 24V)
When pushing a 5.9L Cummins to extreme horsepower levels, the weak point isn't just the bolts—it’s the block itself. To prevent the main caps from walking and the block from flexing, many high-performance builders utilize a main girdle. The ARP 247-5401 kit is specifically engineered with the extra length required to accommodate a main girdle while providing the legendary clamping force of ARP hardware.
This kit is compatible with both the 12-valve and 24-valve 5.9L platforms (1989–2007) that have been equipped with an aftermarket 12mm or 14mm thick main girdle.
Â
Key Features & Benefits
-
Extended Length Design: These studs are specifically longer than standard main studs to account for the thickness of a main strengthening girdle, ensuring full thread engagement and proper nut seating.
-
Premium 8740 Chrome Moly: Heat-treated in-house to a tensile strength of 200,000 psi, providing a massive upgrade in strength and fatigue life over factory bolts.
-
Superior Bottom-End Rigidity: By tying the main caps together with a girdle and ARP studs, you virtually eliminate "main cap walk" and block distortion, which is critical for engines exceeding 800+ HP.
-
Consistent Clamping Force: Studs provide more accurate torque loading than bolts because they do not "twist" into the block. This ensures that the main bearing bores remain perfectly aligned under extreme stress.
-
Black Oxide Finish: Precision machined and finished with a durable black oxide coating for maximum corrosion resistance and long-term reliability.
Â
Why Use Girdle-Length Studs?
If you try to use standard main studs with a girdle, you will not have enough thread for the nut to fully engage, leading to a catastrophic failure of the bottom end. The ARP 247-5401 kit solves this by providing the specific reach needed to secure both the main caps and the girdle to the block webbing.
In high-boost applications, the crankshaft exerts massive oscillating forces. This kit ensures that the entire bottom end of your Cummins acts as a single, rigid unit, protecting your bearings and crankshaft from the "fretting" that destroys high-performance engines.
Important Installation Note: Installation of a main girdle and studs requires the block to be line-honed by a professional machinist. The increased clamping force and the addition of the girdle will change the roundness of the main bearing bores.
