ARP Ultra-Torque fastener assembly lubricant

What is an assembly lubricant for?

On an engine fastener, the figure read on the torque wrench says nothing about the preload actually achieved: much of the effort is absorbed by friction in the threads and under the head. Depending on lubrication, two bolts tightened to the same torque can end up with very different preloads. That scatter is exactly what an assembly lubricant corrects.

ARP Ultra-Torque was formulated to reduce that scatter and to eliminate the need to cycle fasteners (tightening and loosening them several times) before final assembly. It is a blend of extreme pressure lubricants with anti-seize properties, suitable for all high performance engine fasteners.

What the lubricant brings to the build

The benefit is twofold: an accurate preload, and above all a repeatable preload from one fastener to the next.

• Obtains 95 to 100 % of ARP recommended installation preloads on the first pull, without cycling fasteners
• Maintains ARP recommended preloads within 5 % on all remaining cycles
• Stabilises preloads within 5 % across a group of fasteners: cylinder block deck surface, main web, connecting rod cap
• Ensures consistent and repeatable housing and cylinder bore dimensions during machining, mock-up and final assembly, particularly when using a honing plate
• Prevents seizing and galling on threaded fasteners
• Prevents rust and corrosion throughout the life of the lubricant
• High melting point: 182 °C
• Metal free formulation

Available pack sizes

The 14 and 28 g pouches suit single-use jobs on one fastener kit. The 48 g tube covers a complete engine build. The 284 and 567 g containers, fitted with a brush applicator in the cap, are intended for workshop use.

Use

Apply the lubricant to the threads and under the bolt head or nut, then tighten to the torque value specified by ARP for that part number. ARP published torque figures are established with this lubricant: using another product, or assembling dry, changes the preload obtained at a given torque.

Important: lubricant choice is part of the tightening specification. On fasteners checked by stretch measurement, such as rod bolts, lubrication also affects the number of cycles required before stabilisation.