Caterpillar 
Cummins 
Duramax (Chevy/GMC) 
Ford Power Stroke
Acura
Chrysler
Honda
Jaguar Land Rover
Jeep
Mazda
Mini Cooper
Mitsubishi
Nissan
Polaris
Subaru
Toyota
What drivers say about XOTIC PERFORMANCE™
Main Stud Kit - 2008-2010 6.4L Ford Power Stroke
PART # SKU MP875
Verified Reviews
Original price
£364.00
-
Original price
£364.00
Original price
£364.00
£364.00
-
£364.00
Current price
£364.00
Availability:
in stock, ready to be shipped
Limited Lifetime Warranty on All Fasteners
Trusted in 30,000+ Builds
30-Day Satisfaction Guarantee
Free Shipping on Orders $100+
These are main studs, not head studs. Main and head studs serve different purposes—selecting the right one is crucial.
Why Main Studs?
Main studs provide superior clamping force compared to main bolts, reducing wear on block threads and assisting with main cap alignment. Unlike bolts, which twist during tightening, studs remain stationary, reducing the chance of main cap walking under high loads. They are especially beneficial in high-performance applications where increased stability and durability are required.
Disclaimer: Designed to secure crankshaft main bearing caps. This is NOT a head stud kit.
INSTALL GUIDE
This guide covers installation of the XOTIC PERFORMANCE™ MP875 main stud kit for the 2008–2010 6.4L Ford Power Stroke. Prefer a printable copy? Download the PDF manual.
Two stud lengths in this kit — sort them first. The outer studs measure 5.4 inches and the inner studs measure 5.9 inches. Separate them into two piles before anything goes into the block. Both lengths torque to the same final value, but a short stud in a long hole leaves you short of thread engagement under the nut — and you won't discover it until the torque wrench feels wrong.
Why a 6.4L Power Stroke needs main studs
The 6.4L is a compound-turbo engine from the factory, which means it responds to tuning faster than almost anything else in the Power Stroke family — and it means the bottom end gets loaded hard the moment the fuel goes up. Cracked pistons get the headlines on a built 6.4L, but the same cylinder pressure that stresses a piston travels down the rod and into the main cap on every power stroke. Main cap fasteners are what keep the crankshaft bearing bores round and located under that load.
Studs do that better than bolts for a structural reason. A bolt is torqued into the block, so it twists and stretches at the same time; a stud is threaded in finger-tight and stays still while the nut is torqued against it, loading the stud in pure tension. The result is more consistent, more accurate preload — the tensile force in the fastener that becomes clamp force in the joint — and preload is what prevents cap walk and bore distortion. XOTIC PERFORMANCE™ main studs are manufactured from our premium XOTIC 7200 steel alloy and backed by a lifetime warranty.
What's in the MP875 kit
- 20 × main studs (XOTIC 7200 alloy) — 5.4 inch outer and 5.9 inch inner
- 20 × hardened parallel washers
- 20 × nuts
- 1 × socket
- 1 × allen wrench
- 1 × fastener assembly lubricant
Before you start: verify first
Confirm that part number MP875 is compatible with your application before installing any components. Inspect all package contents for damage and clean as necessary to ensure accurate installation. Sort the 5.4 inch and 5.9 inch studs into separate piles now. Report any obvious defects or shipping damage to us before proceeding.
How to install main studs on a 6.4L Power Stroke
- Chase the block threads. Clean the threads in the block with a thread chaser prior to installing the studs, to ensure accurate fitment and precise torque readings. The correct tool here is the M14 x 2.0 chaser (CS301), available separately.
- Thread the studs in by hand — right length, right hole. Screw the main studs in as tight as can be made by hand, with the 5.4 inch studs in the outer positions and the 5.9 inch studs inboard. No tool is necessary and do not apply torque. Loctite may be used for permanent stud installation, but the fasteners must be fully torqued before the Loctite sets.
- Check stud height with a straightedge. Use a straightedge ruler to measure the distance from the mating surface (deck or main cap) to the top of each installed stud. Ensure all studs of the same length group sit level with each other (within 1 mm / 0.040”). Uneven height may indicate debris or incorrect thread engagement. Properly installed studs will bottom out smoothly and show uniform height across all positions. If a stud appears higher or lower than the others, remove it, re-clean the hole, and reinstall by hand. Do not use tools to force studs deeper. Incorrect stud seating can cause off-angle stress, uneven preload, or stud fracture during engine operation.
- Install the main caps. Set the caps in place and ensure appropriate alignment before any load goes on them.
- Lubricate. Using the fastener assembly lubricant included in the package, lubricate the threads of the main studs and the nuts.
- Hand-tighten the nuts. Thread the nuts onto the studs as tight as can be made by hand.
- Torque in three equal steps. Working in the sequence shown in the manual's torque sequence diagram, tighten the nuts in three equal steps to the final value below — roughly a third, then two thirds, then full torque. Never go straight to the final value.
- Check the bores. With the studs torqued, check the main bores for size and roundness before the crank goes back in.
6.4L Power Stroke main stud torque specs
| Stud | Final torque |
|---|---|
| Outer (5.4 inch) | 170 ft-lbs |
| Inner (5.9 inch) | 170 ft-lbs |
Reach 170 ft-lbs in three equal steps across the full sequence — not one stud at a time to final value.
A common mistake to avoid: when torquing a fastener, do not stop short of the recommended value — continue in one motion until the specified torque is achieved. If you accidentally stop short, loosen the fastener and re-torque. Stopping short and "topping up" produces unequal preload distribution across the caps and can leave a bore out of round.
Frequently asked questions
What are the main stud torque specs for a 2008–2010 6.4L Power Stroke?
170 ft-lbs final on both the 5.4 inch outer studs and the 5.9 inch inner studs, reached in three equal steps following the manual's sequence.
Which studs go where?
The 5.4 inch studs are the outers; the 5.9 inch studs are the inners. Sort them before installation.
Do I need to align hone after installing main studs?
Check first. Once the studs are torqued, measure the main bores for size and roundness — studs clamp the caps differently than the factory bolts did. If a hone is needed, do it with the same studs, nuts, and assembly lubricant you'll use for final assembly, torqued to spec.
What thread chaser does the 6.4L block take?
The M14 x 2.0 chaser (CS301). Chasing is not tapping — a chaser cleans existing threads without cutting new material.
While you're in there
A 6.4L on the stand deserves matching hardware top to bottom. See our 6.4L head stud guide (CP875) and the 6.0L/6.4L connecting rod bolt kit (CP115).
Need help?
For technical support, email support@xotic-performance.com. All XOTIC PERFORMANCE™ fasteners are covered by our limited lifetime warranty. Finished your install? Tag #XOTICPERFORMANCE on Instagram for a chance to be featured.
© 2026 XOTIC PERFORMANCE™. This installation guide is an original copyrighted work of XOTIC PERFORMANCE™. Reproduction, distribution, or use of this content in whole or in part without written permission is prohibited. Doc ref: 2025.05.20 (web edition 2026.08).
PACKAGE CONTENTS
VEHICLE FITMENTS
⚠️ PROP 65 WARNING
CALIFORNIA WARNING: Cancer and Reproductive Harm - www.P65Warnings.ca.gov
