Site Information

 Loading... Please wait...
  • Compare
  • Gift Certificates
  • My Account
  • All prices are in USD

Spectrum Sludge - 1 Gallon

This product ships in 1 business day
Calculated at checkout

Product Description

Spectrum Sludge™ is the thickest noise and vibration paste on the market. It will come in the base gallon of Spectrum and the package will include a thickening agent. Simply add a bottle of Sludge Activator (included) to a gallon of our regular Spectrum coating to change the viscosity from chocolate syrup to peanut butter. Spectrum Sludge will still have to be applied in thickness close to 1mm at a time but with 2-3 coats for a total thickness of at least 3mm. Spectrum Sludge can be applied with gloved hand or trowel in the hard to reach places you can't get a spray gun, brush, or roller into with the regular Spectrum. Spectrum Sludge is not intended to skip the "apply in layers" requirement. 

*Spectrum is water based and will require a water based primer to adhere to plastic or fiberglass.

*Application surface should be dry and free from rust, oil, dirt and debris prior application. We suggest using denatured alcohol to clean the surfaces because it does not leave behind a film like degreasers do.

*Do not allow to freeze. If gallon does get frozen do not mix, shake, or move container until completely thawed. Do not apply product in temperatures below 50 degrees Fahrenheit.

Spectrum and Spectrum Sludge are not bedliners they do not get egg shell hard like bedliners, they will hold up to daily driving rocks/mud in wheel wells and under carriages just fine. If you wish to use Spectrum or Spectrum Sludge in your truck/jeep bed or floor area you will need to cover it with a bedliner or other material to protect the Spectrum from heavy weight item hits, rocks in shoes, and other rough treatment that bedliners protect from. 


Noise Reduction Uses...

Whether you are looking to quiet down your hot rod, or make your daily driver comfortable as a luxury car, Spectrum Sludge has proven to be the easiest most efficient vibration paste on the market.

The majority of reducible noise in any car is structure borne, meaning it comes from vibrations, like a wind chime. Unlike wind chimes however, our cars are not tuned to any specific musical frequency, so what we end up hearing is the road noise, engine rumble and exhaust drone.

Stopping the vibrations on your cars metal panels is much like stopping a noisy wind chime with your hand. Once the vibrations stop, the noise stops.

Traditional noise mats are mostly inefficient mass loaders; heavy & foul smelling tar boards that work by adding weight to the car to quiet it down.

Because Spectrum Sludge is a curing polymer, it won`t chip or crack under extreme temperatures or abuse, making it perfect for use as an interior coating or as an undercoating.

When you purchase Spectrum Sludge, you will get 2 containers. The first is a regular gallon of Spectrum, and the second is a small bottle of Sludge Activator. Simply mix the activator in to the gallon of Spectrum to increase the viscosity to the thickness of your liking. The more Activator you add, the thicker it will get. Spectrum Sludge is too thick to be applied with a gun, so a paint brush or putty knife is ideal. 

Activator will not make Sludge dry or harden any faster than normal. It will simply thicken the viscosity from the point of chocolate syrup to peanutbutter.

Mobile Audio

If you have an aftermarket, sound system, then you know that a lot of the musical energy is spent, and even wasted by vibrating and flexing the your cars metal panels. Not only are these vibrations loud, and obnoxious, but they also limit the potential of your stereo.

Since it is a vibration damper it will obviously reduce the panel vibration caused from your speakers allowing your music to sound clearer. It also strengthens the cars panels.

With stronger, non flexing panels, the energy is no longer being wasted and stays inside the car, making your music louder, clearer and less obnoxious to those around you.

Thermal Insulation

 Spectrum Sludge will help reduce heat. Spectrum Sludge is made with Mica, Talc, Calcium Carbonate, and crushed rubber. All of these ingredients help stop thermal transfer.


What is the difference between Spectrum & Sludge?
Spectrum and Sludge are nearly identical. The only difference is the viscosity. Spectrum has the consistency of heavy chocolate syrup and is easy to spray, brush or roll on. Sludge has the consistency of peanut butter and is too thick to spray, but can easily be applied with a putty knife, trowel or paint brush.

How long does Spectrum Sludge take to cure?
like all water based products Spectrum will take 30 full days to cure but will be dry to the touch in 30-60 minutes and mostly dry within 1 week.

When can I put my upholstery back in place?

We suggest that you allow a minimum of 2 days for Spectrum Sludge to dry before reinstalling your upholstery.

What is better, Spectrum Sludge or Damplifier?
Both products are designed to do the same basic function; reduce noise through the reduction of vibrations. Both have their place, and both excel at specific frequency ranges. This is why we suggest using a combination of damping mat and coatings.

We suggest using Damplifier Pro as your base foundation inside the car, on all the panels hidden by upholstery, then use Spectrum Sludge as an undercoating on the underside of the cars floor pan. This will sandwich the sheet metal floor between Damplifier Pro & Spectrum Sludge, allowing for the ultimate approach in vibration deadening.

Does Sludge Activator speed up the curing time of Spectrum?
No. Sludge Activator is only a thickening agent, not a curing or hardening agent. With or without the Sludge Activator, Spectrum will have a shelf life of 6 months once opened and will cure in 30 days once applied.


Weight per wet gallon = 13.2 lbs.|
Weight per cured gallon = 8.5 lbs
Weight per sq. foot @ 40 mils thick =.26
Coverage: 1 gallon = 10 sq ft @ 3mm thickness (2-3 coats)

Spectrum has a shelf-life of six months, provided it's stored at room temperature. Once open it is good for 30-60 days as long as it has been re-sealed tightly.

Suggested Thickness:

Minimum = 40 mils (1mm) thick
Maximum = 120 mils (3mm) thick

*Sludge is water based and will not adhere permanently to plastic or fiberglass without first using a water based primer. 

*Application surface should be dry and free from rust, oil, dirt and debris prior application.

Product Videos

Making Second Skin Spectrum Sludge Sound Deadener 05:01

ANT shows us how to turn Second Skin Spectrum in to Sludge sound deadener

  • Making Second ...
    ANT shows us how to turn Second Skin Spectrum in to Sludge sou...
  • The effectiven...
    Here I show how effective Spectrum Sludge is at reducing vibra...

Product Reviews

Write Review

  1. needs to be applied thick 3 Star Review

    Posted by on 21st Oct 2015

    It does work to dampen resonant body parts, but it needs to be applied thick, at least 3 mm to be effective.

  2. Good for auto applications 5 Star Review

    Posted by on 14th Nov 2013

    I used this on my 1970 Mustang, particularly the rear wheel wells to recreate the "factory" sound deadener look. The product arrived promptly and was easy to use. I used a paint brush to apply it with and without the activator. With the activator, it firmed up well, and quickly. One advantage as well is that it is not really smelly like other products. It dried nicely (takes several days if applied heavily like I did) and looks like I wanted!

  3. BMW M3 Sound insulation 5 Star Review

    Posted by on 16th Jul 2013

    I had to change the trans on my 98 BMW M3. It had a fabric sound insulation there which breaks down after a few yrs and then it starts to sag and starts rubbing against the drive shaft. I wanted something better that wasn't going to break down and came to know of the Sludge. I had the installer put it on and it dried within 20 mins. When I drive I hear no excess noise. Very happy w/ the product and highly recommend. Just wish the shipping was a little cheaper.

  4. Great!!!!! 5 Star Review

    Posted by on 4th Jun 2013

    This product is great but the only downside is it takes a full week to dry....

  5. Sludge is the way to go 5 Star Review

    Posted by on 8th Feb 2013

    After watching the Second Skin video on Sludge I thought this stuff is too good to be true. But it isn't. It is amazing stuff. It was applied to the floor pans of my 1967 Mercedes where it not only lessen the outside noises but appeared to strengthen them. I definitely would recommend Sludge and any other products from Second Skin. Customer service is awesome as well.

  6. After reading what everyone is saying on the forums... 5 Star Review

    Posted by on 6th Nov 2012

    I purchased Second Skin Sludge. After reading what everyone is saying on the forums, seeing the prices and liking the website, I figured I’d give it a shot. Customer service is awesome. Before ordering, I sent several emails regarding the various products and all of my questions were answered. Installing the product was simple enough. I will be ordering a couple gallons more of sludge and some Damplifier Pro so I can line the doors, roof and wheel wells before I have my system installed. Great product and great customer service. Good job Ant.

  7. How quiet the car has become 5 Star Review

    Posted by on 6th Nov 2012

    Man o Man.... Anthony.... Thank you so much for your recommendation to go for the sludge product.... I just completed doing the 4 wheel wells in my 2001 maxima GLE. I used one gallon of sludge and did not even do the full wheel well. I just did the passenger compartment facing sheet metal upto the strut tower where the passenger compartment ends. I also made sure I laid the sludge kind of thick I know its more than 3mm. I took her out for a drive today and man I'm blown away. The tire noise from the back of the car has disappeared. Even my wife today commented as to how quiet the car has become. Thank you once again sir. I think I am going to go ahead and save up some money to sludge the wheel wells of my 330ci next...

Find Similar Products by Category