***We will be CLOSED Setpember 11th-20th, 2021.*** Any Orders placed will be processed when we return. Turbos and plenums are made to order and will have additional lead time. PT Wiring branded items are delayed approximately 1 additional week. As always, we appreciate your support of our small business and look forward to working with you!


Main Stud Kit

Quadstar Tuning LLC

  • $369.00


6.2 and 6.5 diesel chromoly steel main stud kits!  We highly recommend these for any 6.2L or 6.5L diesel build to address the main web cracking issues.  If we won't build one without them, you shouldn't either!  Made in the USA with a 190,000 psi tensile-strength rating. They are precision centerless-ground and thread-rolled to Mil-S-8879 specs, with a black oxide finish for corrosion resistance.

The kits come complete with hardened washers and high-strength 12pt hex nuts.  They do not come with a "girdle".  Two styles are available due to variations in block designs. Please select the one you need before adding to the cart and message us with any questions before-hand:

  • Each kit includes 20  studs, 20 nuts and 20 washers for complete main cap coverage!
  • 1997 & Earlier GM #599, #141, etc. with 12mm outer main fasteners
    • Compatible with 6.2L and 6.5L blocks
  • 1997.5 & Later GM #506 6.5L with 10mm outer main fasteners


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