McLeod Racing RST HD Twin w/ Steel Flywheel - 97-15 GM LS 6 Bolt Crank - 1-1/8 x 26 Spline - 168T
Built an LS1, LS2, LS3 or LS7 past what the factory clutch can hold? The McLeod 6405507MD is the RST HD twin disc packaged with a steel flywheel for 1997 to 2015 GM LS engines with the 6-bolt crankshaft flange. It uses a 168 tooth ring gear and 1-1/8 x 26 spline discs, and it is aimed at the owner whose stock or single-disc clutch now slips in the upper gears, chatters, or needs a pedal so stiff that traffic is miserable.
A single disc can only grow so much in diameter or clamp load before the pedal gets heavy. McLeod's answer is two smaller discs and a floater plate, which doubles the friction surfaces inside the same bellhousing. The RST HD sits between McLeod's street RST and the harder-hitting RXT. Each disc is faced with full organic material on one side for a soft, progressive take-up, and segmented ceramic on the other side for grip when the engine is making real power. McLeod rates it for up to 950 horsepower and says the pedal is lighter than stock.
This version comes on a steel flywheel. Compared with aluminum, steel stores more rotating energy, so a heavy F-body, GTO or LS-swapped truck launches with less slip and is easier to creep in a parking lot. The shipping weight of this kit is about 49.5 lb, so plan on a helper or a transmission jack for the install.
Do a load test: fourth gear around 2,000 rpm, then full throttle. If the tach jumps ahead of road speed, the clutch is slipping. Before blaming the friction, bleed the hydraulics and check for a leaking slave or a pedal that sinks, because a release bearing that never fully returns will make a healthy clutch slip. Our slipping diagnosis guide walks through separating clutch slip from other causes, and the manual vs automatic repair cost guide helps you budget the labor.
McLeod lists this kit for 1997-2015 GM LS engines with the 6-bolt crank, a 168 tooth ring gear and a 1-1/8 x 26 input spline. GM introduced the LS family in 1997, and the 6-bolt flange covers most of the engines people swap and modify. The listing is engine based, not vehicle based, so before ordering count the bolts holding your current flywheel to the crank, confirm your starter works with a 168 tooth ring gear, and confirm your gearbox input is 1-1/8 x 26. If you count eight bolts, you need the 8-bolt LS-X version of this RST HD kit. If you want to keep a lighter rotating assembly, McLeod also makes an aluminum flywheel for 1997-up LS engines. Not sure what you have? Send us the engine, transmission and VIN and we will check it. More clutch parts are in our hard parts section.
| Brand | McLeod Racing |
| Part number | 6405507MD |
| Fits | McLeod Racing RST HD Twin w/ Steel Flywheel - 97-15 GM LS 6 Bolt Crank - 1-1/8 x 26 Spline - 168T |
| Type | Clutch Kits - Multi |
| Condition | New |
| Ships | Same business day (in stock), from the USA |
| Warranty | 1-year |
If the engine is a 6-bolt crank LS from 1997-2015, the bolt pattern matches. You still need a transmission with a 1-1/8 x 26 input and a starter that works with a 168 tooth ring gear. Send us the VIN and transmission if you are unsure.
Count the bolts that hold the flywheel to the crankshaft. Six bolts means this kit. Eight bolts means the 2009-up LS-X 8-bolt version.
That is the point of the RST HD. The organic side of each disc gives a smooth take-up, and McLeod says the pedal is lighter than stock, while the ceramic side adds holding power up to 950 horsepower.
A new pilot bearing, the release bearing if it is worn or not set up for a twin, and the rear main seal if it is weeping. Bleed the clutch hydraulics with fresh fluid when you are done.
Yes. McLeod calls for roughly 1,200 normal engagements in street driving before hard launches so the friction surfaces seat.
