


The Cummins ISF 2.8L is a compact, high-torque engine that has become a favorite for both light commercial use and custom off-road swaps. However, as boost levels are increased through performance tuning, the stresses on the bottom end grow exponentially. The ARP 247-5407 Main Stud Kit provides the essential structural reinforcement needed to keep your crankshaft perfectly aligned and your main caps securely anchored to the block.
By upgrading from the factory "torque-to-yield" bolts to ARP2000® studs, you are creating a rock-solid foundation for your ISF 2.8L build.
ARP2000® Material: Unlike standard main stud kits, this kit is manufactured from proprietary ARP2000 alloy, heat-treated to a tensile strength of 220,000 psi. This offers a significant strength advantage over 8740 chrome moly and factory hardware.
Eliminates Main Cap Walk: High combustion pressures can cause main caps to shift or "walk," leading to fretting on the block and premature bearing failure. These studs provide the massive vertical clamping force required to lock the caps in place.
Superior Torque Accuracy: Because the stud remains stationary and only the nut rotates, you eliminate the torsional (twisting) stress common with bolts. This results in a much more consistent and accurate preload on the main journals.
Rolled Threads: The threads are rolled after heat treatment, which gives the fasteners roughly 2000% (20x) better fatigue life than studs threaded before the hardening process.
Black Oxide Finish: Precision machined and finished with a durable black oxide coating for maximum corrosion resistance and long-term reliability in the harshest engine environments.
The ISF 2.8L is built for efficiency, but performance enthusiasts often push these engines to double or triple their stock power output. When you increase the fuel and air, the downward force on the crankshaft journals becomes immense. If the main caps move even a fraction of a millimeter, the oil film protecting your bearings is compromised.
The ARP 247-5407 kit is the "peace of mind" solution for any ISF rebuild. Whether you are building a reliable daily driver or a high-boost off-road project, these studs provide the structural integrity your block needs to survive.
Machinist's Note: Because ARP studs provide a significantly higher clamping force than factory bolts, it is highly recommended to have the block line-honed with the new studs installed. This ensures the main bearing bores remain perfectly round and true under the higher tension.
PLEASE READ AND FILL OUT THE WARRANTY REGISTRATION FORM TO ACTIVATE THE WARRANTY.

Supplied with every engine is a complete copy of our warranty with an attached warranty registration form. This form can also be found here. Once filled out:
Then email a copy of each document within 45 days from the time of purchase to warranty@choateperformance.com. You should also retain a copy for your records as it may be required to assist with a warranty concern.
MODEL C STANDARD WARRANTY
1 Year / Unlimited Miles

THIS WARRANTY IS WITH THE PURCHASE OF THE INSTALLATION PACKAGE AND IS FOR THE ENGINE/WORKMANSHIP ONLY. NO LABOR PAYOUTS.
EXTENDED COMMERCIAL WARRANTIES ARE NOT AVAILABLE ON WORKHORSE, CASSQUATCH RACE SERIES, OR MODEL C ENGINES.
Remanufactured Heads — 6 Months
PARTS ONLY

Cylinder heads are warranted to be free from defects in material and workmanship. This warranty does not cover cylinder heads that are damaged due to improper installation, overheating, abuse, or accident.
Short Block Engines

Warranty coverage for Short Block engines does not include labor payout. We do not cover fluid leaks on any Short Block builds.
DAILY DRIVER WARRANTY
5 Year / 100,000 Miles

THIS WARRANTY IS NOT A FULL COVERAGE WARRANTY. PLEASE REVIEW YOUR WARRANTY CAREFULLY.
Labor rate for PREFERRED DEALER ONLY is a higher shop rate using Mitchell flat rate time.
WORKHORSE SERIES ENGINE
5 Year / 100,000 Miles

THIS WARRANTY IS NOT A FULL COVERAGE WARRANTY. PLEASE REVIEW YOUR WARRANTY CAREFULLY.
Labor rate for PREFERRED DEALER ONLY is a higher shop rate using Mitchell flat rate time.
YOUR CASSQUATCH RACE ENGINE
6 Months / 3,000 Miles
PARTS ONLY

THIS WARRANTY IS NOT A FULL COVERAGE WARRANTY. PLEASE REVIEW YOUR WARRANTY CAREFULLY.
CHOATE ENGINEERING PERFORMANCE COMMERCIAL WARRANTY
1 Year / 20,000 Miles

THIS WARRANTY IS NOT A FULL COVERAGE WARRANTY. PLEASE REVIEW YOUR WARRANTY CAREFULLY.
Labor rate for PREFERRED DEALER ONLY is a higher shop rate using Mitchell flat rate time.
CHOATE ENGINEERING PERFORMANCE EXTENDED COMMERCIAL WARRANTY
3 Year / 60,000 Miles

THIS WARRANTY IS NOT A FULL COVERAGE WARRANTY. PLEASE REVIEW YOUR WARRANTY CAREFULLY.
WARRANTY COVERAGE DETAILS
This warranty will cover remanufactured Short and Long-Block engines that are built by Choate Engineering Performance unless otherwise stated. From this page on, engines will be referred to as “unit(s)” and/or “engine(s)” unless otherwise stated. Fuel pump, injectors, and turbo warranties, and warranties on all accessories, are covered by the supplying manufacturer’s warranty.
FOR PREFERRED DEALERS ONLY: LABOR RATE IS SET AT A HIGHER RATE PER HOUR UP TO A MAXIMUM OF $2,500, NO EXCEPTIONS.
THE LIMITED WARRANTY WILL BE VOID AND WILL NOT APPLY TO DEFECTS OR FAILURES CAUSED BY THE FOLLOWING:
BUYER ALSO ACKNOWLEDGES THAT PROPER MAINTENANCE PROCEDURES ARE REQUIRED TO KEEP THE UNIT IN PROPER WORKING ORDER. CHOATE ENGINEERING PERFORMANCE WILL NOT ASSUME ANY RESPONSIBILITY FOR THE COST OF THIS ROUTINE MAINTENANCE.
Buyer acknowledges the following:
This warranty will not cover damages caused by the following for remanufactured engines:
Choate Engineering Performance limited warranty will end after the expiration of time or mileage from the date of the original invoice. Any repairs or replacements will not extend the warranty. The buyer shall be responsible for all defects thereafter, regardless of cause. Choate Engineering Performance limited warranty is in lieu of all other warranties expressed or implied.
The buyer agrees Choate Engineering Performance will not be responsible for:
TO QUALIFY FOR THE 5 YEAR / 100,000 MILE WARRANTY YOU MUST FOLLOW ALL INSTRUCTIONS AND REPLACE ALL PARTS SPECIFIED.
THIS WARRANTY IS TRANSFERABLE THROUGH PRIVATE SALE AND CHANGE OF OWNERSHIP ONLY ONCE IF CERTAIN CRITERIA ARE MET.
CHOATE ENGINEERING PERFORMANCE LIMITED WARRANTY FOR THE WORKHORSE AND CASSQUATCH SERIES ENGINES IS IN ADDITION TO ALL ITEMS LISTED IN THE STANDARD WARRANTY PACKAGE AND SUPERSEDES ALL MILEAGE REQUIREMENTS.
The Limited Warranty specifically does not cover the following:
FREIGHT / SHIPPING CHARGES

CHOATE ENGINEERING PERFORMANCE SHALL NOT BE RESPONSIBLE, NOR SHALL IT PAY ANY FREIGHT/SHIPPING CHARGES.
ADDITIONAL INFORMATION

As consideration for the above warranties, the buyer agrees they will take no action, statement, characterization, or implication regarding Choate Engineering Performance that may in any manner be interpreted as disparaging to Choate Engineering Performance or the reputation of Choate Engineering Performance. Any violation of this is a material breach, entitling Choate Engineering Performance to void any warranty.