Red Line Friction Modifier / Break-In Additive 4oz - Universal
Red Line Friction Modifier / Break-In Additive 4oz - Universal
Red Line
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PRODUCT DETAILS ▾
RallySport Direct is proud to bring you some of the best lubricants in the industry brought to you by Red Line.
Here, you are looking at the Red Line Limited-Slip Differential Friction Modifier / Break-in Additive. This additive has been designed to significantly reduce the friction break-in of differentials. Limited-Slip or Positraction units use plates or clutches to provide the proper amount of lock-up to the differential. Slippery lubricants are required to prevent chatter, but too much slipperiness causes excess wheel spin, reducing traction.
The Red Line Limited-Slip Differential Friction-Modifier / Break-In Additive will significantly reduce the friction during the break-in of differentials. High temperatures encountered in break-in can destroy the hardening of the gear teeth causing rapid wear of the softened gears. This additive can reduce the break-in temperatures by as much as 50°F, improving break-in conditions. Compatible with petroleum or synthetic gear oils. Red Line Gear Oils already contain this additive (except the NS).
DETAILS:
- Compatible with both petroleum and synthetic gear oils
- Reduces break-in temps as much as 50°F
- Add 1oz at a time to clutch-type limited-slip or positraction units to prevent chatter
- Sold in a 4oz container
WHY WE CARRY THIS ▾
We only list parts we’d run ourselves or recommend to a friend building a real car. If it feels vague, unverified, or inconsistent, it doesn’t make the cut.
- Fitment-first mindset — no “universal” roulette
- Brand reputation matters — we favor proven manufacturing
- Support that actually responds with real answers
WHAT TO EXPECT ▾
This is the clean path: correct fitment, clean install, and results that match the intent.
- Install-ready experience with correct mounting where provided
- Finish that holds up to real driving, not just photos
- Selections on this page drive the exact fitment shipped
TRUST, BUILT INTO THE PROCESS.
Anyone can list parts. We curate what belongs on a serious build. Our goal is simple: fewer surprises, cleaner installs, and confidence when you hit “Buy.”
Fitment checked
We prioritize vehicle-specific listings and clear selection logic so you’re not gambling on compatibility.
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Proven manufacturing and consistent quality matter more than hype. We bias toward what actually holds up.
Real support
If you have a question, you’ll get a human answer that helps you finish the build — not a copy-paste shrug.
RallySport Direct is proud to bring you some of the best lubricants in the industry brought to you by Red Line.
Here, you are looking at the Red Line Limited-Slip Differential Friction Modifier / Break-in Additive. This additive has been designed to significantly reduce the friction break-in of differentials. Limited-Slip or Positraction units use plates or clutches to provide the proper amount of lock-up to the differential. Slippery lubricants are required to prevent chatter, but too much slipperiness causes excess wheel spin, reducing traction.
The Red Line Limited-Slip Differential Friction-Modifier / Break-In Additive will significantly reduce the friction during the break-in of differentials. High temperatures encountered in break-in can destroy the hardening of the gear teeth causing rapid wear of the softened gears. This additive can reduce the break-in temperatures by as much as 50°F, improving break-in conditions. Compatible with petroleum or synthetic gear oils. Red Line Gear Oils already contain this additive (except the NS).
DETAILS:
- Compatible with both petroleum and synthetic gear oils
- Reduces break-in temps as much as 50°F
- Add 1oz at a time to clutch-type limited-slip or positraction units to prevent chatter
- Sold in a 4oz container
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