Now that I have your attention.

The thread regarding graying bed liners got me to thinking. (That in itself is very disturbing.)

This is from Nissan's marketing guru's:

"Sourced from PPG, nearly 5-gallons of material are applied at the end of the assembly line. Sprayed in variable thicknesses (2-mm on the bottom and 1-mm on the sides), the elastomer coating is formed from a two-component system which cures to create a tough slip-resistant coating. In addition to preserving the bed itself, additional benefits of this spray-on bedliner include the dampening of sound, road noise, and vibration from the bed area. This new for '04 model has an optional (standard on the LE version) spray-on bedliner which is more durable than a traditional drop-in bedliner and stronger than other aftermarket spray-on bedliners, according to Stove Younan, Nissan marketing. Applied by a robot at Nissan's new Canton, Miss., plant, the Durabed Liner was developed by PPG with input from Nissan. It is made "from a high performance elastomer coating formed by a two component system that when combined reacts to create a polymer chain that crosslinks with other chains to form a tough, high, light and moisture resistant coating," says Nissan. It was developed out of a need for high bed protection but also compatibility with the company's tie-down channel system. The bedliner is applied after the truck has been painted and resists gauging by tools, shovels or sharp objects placed in the truck. Since it has a non-skid surface, bed cargo will not move around during transit. Because it does not "sit" on top of the bed, rust will not develop beneath it like traditional drop-in bedliners, it also avoids road noise and vibration and dampens sounds unlike drop-in units. The weatherproof bedliner is factory applied and therefore warranted by Nissan. The company plans to sell repair kits in the event something does scratch or gouge the bedliner."

Now for the boring technical mumbo jumbo:

Polyurethane Effects Coloration

A wide variety of colorants are available which are suitable for the coloration of polyurethane. The choice of colorant and the mode of incorporation varies with the type of polyurethane and the end application. Our bed liners are a two component polyurethane application. Two component systems are colored almost exclusively by dispersed pigment pastes. These are based on polyols or compatible plasticizers and are either stirred into the polyol component prior to mixing or metered directly into the reaction components at the mixing head of the foaming/dispensing machine.Preference is given to organic pigments because of their high color strength and non-abrasive nature, which prevents excessive wear in the mixing heads.

Thermoplastic PUR resins for melt processing may be colored without difficulty with many of the medium and high performance organic pigments used traditionally for PVC. Such pigments are available as powders and in selected cases as predispersed forms. However, the higher processing temperatures sometimes encountered in injection molding may occasionally cause difficulties with simple pigment types, which have the tendency to go into solution. Spread coating applications, such as artificial leather are commonly colored by dispersed pigment pastes.

Molded Foams, RIM, Integral Skin

Polyurethane RIM products are colored almost exclusively by dispersed pigment pastes. These are based on polyols or compatible plasticizers and are either stirred into the polyol component prior to mixing or metered directly into the reaction components at the mixing head of the foaming/dispensing machine. Preference is given to organic pigments because of their high color strength and non-abrasive nature, which prevent excessive wear in the mixing heads. As the majority of applications are automotive, there is a strong requirement to use colorants with high lightfastness and weathering.

Durability & Protection

We make plastics, rubber and synthetic fibers more durable and protect them from sun and heat. Polymers degrade as a consequence of heat, shear, impurities and oxygen. Polymers are subjected to oxidation at every stage in their life cycle - during manufacture and processing as well as during storage and end use.

Polymer degradation through oxidation can change the aesthetic appearance of the product and can destroy its functional properties. The mechanical properties and the color of the polymer may change upon processing.

Content Protection: colorants, UV filters and oxygen scavengers protect the contents of products packaged in plastic. For example, they protect the taste of beer in PET bottles.

Light Stability & Weather Resistance: UV stabilizers protect plastic products from degradation due to UV light.

Processing Stability: processing stabilizers prevent the polymer degradation during processing. These are antioxidants which are incorporated into the polymer. For the processing consistency of colored applications, specific pigments and pigment preparations have been developed.

Thermal Stability: the use of antioxidants prevents polymer degradation through oxidation by controlling molecular weight changes which lead to a loss of physical and aesthetic properties.

If you have come this far, you are saying, “But Joe, what does all this bull$hit mean?” I will venture a guess and say the number of “grayed” bed liners is a small percentage of the total number produced. If someone has real production numbers, I would like to know. This issue raises several questions regarding liners turning color. Did Nissan/PPG perform enough environmental testing? Does one part of the country experience more failures than another? Could it just be a case of certain batches did not contain the proper amount of additives and stabilizers? Is this problem mostly on 2004 and early production 2005’s? Any ’06 or ’07 models in question? I don’t know!?

Your thought and comments are welcomed.

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May God Bless America!



2005 LE KC 4x2
A15 w/Steel, W07, N94, L92, Hellwig, Burtman SS Door Trim, Chrome Tailgate and Fog Lamp Trim, OEM Bug Deflector and Side Steps, Armada Air Dam, LED Brake/Taillights.

So far as I know, the TSB for white liners applies only to bed liners produced in '05. I suspect that it was a chemical problem with product shipped directly from PPG to Nissan.

As I've stated before, my SM thought it might have something to due with improper UV protection in the final coating.

I didn't notice a problem with the liner until after the ambiant air temp at night got below 35* F.

The actual surface of the bedliner did not appear to be very different, just the coloration.

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05 KC SE Smoke
01 Suzuki 600 GSF
88 Fiero 2M4

If you can scrape the white stuff easily with your fingernail, it's oxidation. As you say, improper amounts of UV protection in the batch.

I don't think I was able to scrape anything with my fingernail. The surface was sill in tact, just discolored.

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05 KC SE Smoke
01 Suzuki 600 GSF
88 Fiero 2M4

I remeber seeing some data on this a while back and I'll go track it down so I don't throw out the wrong info.