Recently, I had an experience with Red Line friction modifier that I would like to share. This should help others who may experience the same problem.
My 2014 Mustang GT after BMR suspension and DSS Carbon Fiber driveshaft improvements exhibited deceleration gear whine on the coast side of the ring and pinion. Instead of trying to battle it out with the local dealer, avoiding their excuse not to fix it because the car isn't stock, I opted for the next bext thing.
Red Line Heavy Shockproof gear oil
One of the desirable benefits of HSP is the formulation's ability to quiet gear noise, which it did help. However, the choice to also use their friction modifier is where the problem comes in.
Red Line Friction Modifier
I used the entire bottle, yet still had weird noises from the differential on sharp turns, no matter if they were fast or slow. The rear end would emit a moaning sound, as if the entire rear end was a musical instrument at perfect resonance. Not only is it embarrassing, it was loud. I'm sure people standing near the car could hear the noise as I would drive.
For reference, my rear end with Ford Racing's aluminum cover took almost all 3 quarts, so there is a good bit of gear oil in there.
This morning, I drove to my local Ford dealer and purchased one bottle of XL-3 Motorcraft friction modifier. Not having any Amsoil Slip Lock on hand, this was the next best thing. Honestly, I should have used Amsoil Slip Lock the first time, however, at least I can share this experience with others so they do not repeat it.
Needless to say, XL-3 made the rear end OEM quiet again on sharp turns. Success! Now, is it because there was not enough Red Line Friction Modifier in the rear end, requiring more, or....is it simply not the correct product for our application. I am not going to invest the money to find out, leaving things as is.
From this day forward, I will still recommend Red Line Heavy Shockproof for noisy gears, but will not suggest using Red Line Friction Modifier.
Either use Motorcraft's XL-3 or Amsoil Slip Lock. I've used both with excellent "quieting" results.
My 2014 Mustang GT after BMR suspension and DSS Carbon Fiber driveshaft improvements exhibited deceleration gear whine on the coast side of the ring and pinion. Instead of trying to battle it out with the local dealer, avoiding their excuse not to fix it because the car isn't stock, I opted for the next bext thing.
Red Line Heavy Shockproof gear oil
One of the desirable benefits of HSP is the formulation's ability to quiet gear noise, which it did help. However, the choice to also use their friction modifier is where the problem comes in.
Red Line Friction Modifier
I used the entire bottle, yet still had weird noises from the differential on sharp turns, no matter if they were fast or slow. The rear end would emit a moaning sound, as if the entire rear end was a musical instrument at perfect resonance. Not only is it embarrassing, it was loud. I'm sure people standing near the car could hear the noise as I would drive.
For reference, my rear end with Ford Racing's aluminum cover took almost all 3 quarts, so there is a good bit of gear oil in there.
This morning, I drove to my local Ford dealer and purchased one bottle of XL-3 Motorcraft friction modifier. Not having any Amsoil Slip Lock on hand, this was the next best thing. Honestly, I should have used Amsoil Slip Lock the first time, however, at least I can share this experience with others so they do not repeat it.
Needless to say, XL-3 made the rear end OEM quiet again on sharp turns. Success! Now, is it because there was not enough Red Line Friction Modifier in the rear end, requiring more, or....is it simply not the correct product for our application. I am not going to invest the money to find out, leaving things as is.
From this day forward, I will still recommend Red Line Heavy Shockproof for noisy gears, but will not suggest using Red Line Friction Modifier.
Either use Motorcraft's XL-3 or Amsoil Slip Lock. I've used both with excellent "quieting" results.
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