The best LS engine mount bolts are application-specific flange-bolt kits that match the engine mount-to-block connection. The Z Whip kit is a strong fit for buyers seeking an eight-bolt set with stated LS truck-engine coverage; ICT Billet offers Grade 10.9 zinc-coated hardware; and ARP is the option to consider for performance-focused builds. Check your engine and mount configuration before ordering, because engine stand bolts and general motor mount hardware may serve different purposes.
| Product | Best For | Key Detail |
|---|---|---|
| Z Whip LS Bolt Kit | LS truck applications | Eight clear-zinc-coated Grade 10.9 flange bolts |
| ICT Billet Bolt Kit | Corrosion-conscious replacement | Grade 10.9 zinc-coated bolts |
| ARP 134-3103 | Performance-oriented builds | 874 chromoly construction |
| A.A. LS Bolt Kit | Broadly listed Gen III and IV engines | Hardened, zinc-coated Grade 10.9 bolts |
| Dorman 81101 | Specified vehicle replacement needs | Grade 8 kit; verify exact fitment |
Z Whip LS Engine Mount Bolt Kit
Best for: Buyers who want a complete eight-bolt set for a listed GM LS truck-engine application. The kit is described as eight flange bolts for fastening the engine mount to the engine block. Its stated coverage includes Chevrolet LS truck engines from 1997–2014 and several 4.8L, 5.3L, 6.0L, and 6.2L engine codes.
The bolts are listed as metric Grade 10.9 with a clear zinc coating intended to help resist rust and corrosion. This makes the kit a direct comparison choice for buyers prioritizing stated strength grade, finish, and quantity in one package.
Limitation: The listed fitment is broad, but buyers should confirm their specific engine and mount before purchase rather than relying on displacement alone.
ICT Billet LS Mount-to-Block Bolts
Best for: LS owners seeking heavy-duty Grade 10.9 flange bolts with a protective zinc coating. ICT Billet lists compatibility with a range of LS-family engines, including LS1, LS3, LS6, LSX, LM7, LQ4, LQ9, and others.
The product features emphasize high-strength bolts and zinc coating for corrosion protection and reduced risk of thread seizing. Choose this kit if those specifications matter and the listed engine application matches your build.
Limitation: The supplied product details do not state the package quantity or provide a full vehicle-specific fitment list. Verify what is included and confirm the application before ordering.
ARP 134-3103 Motor Mount Bolt Kit
Best for: Performance-oriented LS builds where the buyer is comparing specialized fastener materials. ARP describes these bolts as securing motor mounts to the block and lists 874 chromoly construction, a black oxide finish, and tensile strength rated at 17,000 psi.
The product information says the hardware is superior to Grade 8 hardware. That makes it a distinct alternative to the zinc-coated Grade 10.9 kits in this list for buyers focused on the stated material and strength claims.
Limitation: The supplied details do not list a full set of compatible engine codes or package contents. Confirm the kit’s application and included hardware for your exact installation.
A.A. LS Engine Block Bolt Kit
Best for: Buyers looking for a kit whose listed fitment names a wide range of Chevrolet Gen III and IV small-block engines. The product details cover 4.8L through 6.2L applications and list numerous LS and Vortec engine codes.
The bolts are described as hardened steel, Grade 10.9, and zinc coated. This is a useful option to compare with other LS-specific kits when the engine code appears in the listing and corrosion-resistant finish is desired.
Limitation: Broad engine coverage does not guarantee fitment with every engine mount or swap configuration. Match the application details to the block and mount being installed.
Dorman 81101 Motor Mount Bolt Kit
Best for: Buyers replacing a missing or fatigued original bolt when Dorman’s specified vehicle fitment matches their application. The product is described as a direct replacement designed to match the fit and function of a factory part for specified years, makes, and models. It is also identified as Grade 8.
Choose this option when you can verify the exact vehicle application in the product fitment information. Its replacement-focused description makes it different from the LS-engine-code-focused kits above.
Limitation: The supplied details do not identify LS engine codes or specific vehicles. Do not assume it fits an LS swap or every GM engine mount; confirm exact fitment first.
Buying Guide: How to Choose LS Engine Mount Bolts
Are you fastening the mount to the engine block?
Confirm the bolt’s intended location before buying. The products listed here are presented as motor mount or mount-to-block hardware, but some similarly named kits are designed for engine stands, starters, or other components. For example, an engine stand bolt kit is not automatically the correct kit for attaching a vehicle’s engine mount to its block.
Which engine and mount configuration do you have?
Check the engine family, engine code, model year, and mount arrangement. A listing that covers several LS or Vortec engines is a starting point, not a substitute for verifying your specific combination. This is especially important for swaps, where the engine and mount may not have been installed together originally.
How should you compare bolt specifications?
- Strength grade: Several kits state Grade 10.9; ARP lists 874 chromoly construction and a tensile-strength figure; Dorman identifies Grade 8 hardware. Compare only the specifications actually provided.
- Finish: Zinc-coated bolts are listed for corrosion protection. ARP’s listed finish is black oxide.
- Quantity: Z Whip specifies eight bolts. Check package contents when the listing does not state a quantity.
- Thread and dimensions: Confirm thread, length, and flange style against the installation requirements. Do not infer dimensions from an engine-family name.
Should you choose an engine-specific kit or a general replacement?
An LS-specific kit is easier to evaluate when its listed engine codes match your application. A general replacement kit can be suitable when the exact vehicle fitment is confirmed. If important details such as bolt length, quantity, or fitment are missing, verify them before ordering rather than assuming they match.
Frequently Asked Questions
What do LS engine mount bolts connect?
In the products listed here, they are described as hardware for securing a motor mount to the engine block. Verify the intended connection for your specific kit.
Are LS engine mount bolts interchangeable with engine stand bolts?
Not necessarily. Engine stand kits may be intended for supporting or attaching an engine to a stand. Confirm the stated purpose and dimensions before using them for a vehicle mount.
Is Grade 10.9 the same as Grade 8?
No. They are different fastener grading systems. Compare the grade stated by the product maker and follow the requirements for your application.
Do zinc-coated bolts prevent all corrosion?
No. Zinc coating is listed as corrosion protection, but the product details do not claim that it prevents corrosion in every condition.
What should I verify before ordering?
Check the engine code, mount-to-block application, bolt quantity, thread and length, and the exact fitment information for the selected kit.