What causes cracked dash ?

[RFP]

I am aware that the factory dash is susceptible to cracking over time, and I'm wondering why. Is it sun and heat or simply "old age?" The dash on my '87 is perfect, and I would really like to keep it that way!

Thanks,

Rob

[Trackrash]

Mostly sun, I think. I replaced my dash with a new one in '85. It still looks almost new, with no cracking. When my car is not garaged and will be outside for any length of time I use a cover.
Up until '05 it was my dd and I always covered it when parked at work.

[Targalid]

The plastic dash material, vinyl polymer, is combined with a relatively non-volatile plasticizer to keep it flexible during its planned life. The usual plasticizer in those days when our cars were manufactured was di-n-octyl phthalate. Volatile is a relative term. Over time, the relatively non-volatile plasticizer is lost due to evaporatiion, especially in high heat areas. Loss is minimized by keeping the plastic parts in the shade. Garaged cars crack less than those left outdoors. I suspect, though I do no know for sure, that better quality vinyl treatments such as Vinylex contain small amounts of plasticizer which will be absorbed by the vinyl and help keep it flexible, thus preventing cracks. I have not found any way to restore cracks once formed.

[964TargaC2]

Rob

Start using Aerospace 303 now and dont worry about the dash

Armor all and the like is a No No

[RFP]

Originally Posted by 964TargaC2

Rob

Start using Aerospace 303 now and dont worry about the dash

Armor all and the like is a No No

Thanks, that's exactly what I've been using since I became the owner... I'm pretty sure the PO used 303 also. I'm going to head out to the garage and give it another "treatment!"

Rob

[RSBob]

The car has the original dash. The PO always kept the car garaged and used a folding sun shade and the dash only has a minor ripple which all but disappeared with leather dye. Now I almost always use the sun shade when parked outside for extended periods. I also use the 303 product.

[IROC]

Originally Posted by 964TargaC2

Start using Aerospace 303 now and dont worry about the dash

I've been using this stuff for over 20 years (along with religious use of a sun shade) and my factory dash from December of 1975 is perfect. Keep the sun off it for sure!!

[Richard C2S]

Guys,

My dash is leather (full leather interior). The car ('81 SC) has almost always been garaged. I've used Lexol leather cleaner and leather treatment on the dash but find that it causes a reflection on the windshield. I know that 303 protects from UV, but I don't think it nourishes the leather.

Any suggestions for nourishing, protecting without causing a reflection?

Thanks.

[twistoffat]

The dash covering is fixed to the dash and with heat via sunlight oth expand at differing rates. Its only minimal but after a while it cracks. Keeping the covering treated and flexible is paramount to longevity as much as trying to avoid too much direct sunlight/heat